DE4403154A1 - Water-discharge installation arranged at a considerable depth beneath the ground, and method of operating the installation - Google Patents

Abstract

Provided in the ground, at a considerable depth, is a duct into which there flows rainwater from flood-regulating ducts, pipelines and rivers, through vertical shafts. The pumping shaft of a pumping station is connected to the downstream end of the underground duct. Water flowing into the pumping shaft is delivered by a pump to a discharge tank. All in all, the pump is arranged on a central water level of the underground duct. The lowest water level LWL which permits a discharge is the central water level of the underground duct. The installation may operate with open duct flow and closed duct flow. In the case of open duct-flow operation, the water level of the underground duct is kept at the lowest water level LWL. In the closed duct-flow operation, the underground duct is filled with water, it being possible for the water level in the vertical shafts to rise. By changing an outflow factor in accordance with a precipitation pattern, the quantity flowing into the vertical shafts can be accurately determined, with the result that the water-discharge installation arranged at a considerable depth beneath the ground can be operated in a stable manner. <IMAGE>

Description

The invention relates to a angeord in great depth nete water drainage system and a method of operation the plant.

It is already known to arrange such a system that the influx, such as rainwater and the like, in Water channels flow to which small rivers too are calculated and collected in an inflow channel, which is located underground. The collected influx is led to a pumping station and from there to a River, into a canal or into the sea.

The operation can take place in a flow in the open Canal take place, drainage water from flooding protection channels in the floor area or in its vicinity are arranged, flows through vertical shafts and then via an underground water channel to the pumping station which is carried out at great depth under the ground area located. This creates a free space in the under maintain earthly channel above water level d. H. the canal is not completely drained filled.  

Operation can also take place when the duct current is closed take place in which the draining water through the under earthly channel so that it flows the channel completely fills out.

To avoid the danger when operating with open channel flow a minimum to reduce that water from the vertical Manholes overflowing to the ground surface when that starts flowing water abruptly in the underground channel flows, this channel has a large capacity, d. H. a diameter of 12.5 m, for example the water level in the underground channel is low can be held.

The level at which an impeller on the downstream side pump provided towards the end of the underground channel works, must be below the discharge level of the underground channel so that the channel is always emptied can. So the lowest water level is near the ground of the underground canal. The one in the pump The pump arranged in the station is fixed beforehand Started water level in a pump shaft stop and stop.

On the other hand, it works with the channel closed electricity the pump if at least the underground channel is filled with water and the water level continues into the vertical shafts increases. This condition occurs if the amount of inflow is the discharge capacity of the pump exceeds.

To estimate the volume flow into the pumping station the amount of rain according to precipitation information tion and the amount of electricity in each  vertical shaft according to an outflow factor estimated for the ratio of this rainfall amount related to the amount of rainwater flowing into the rivers flows out, is representative. The amounts of the currents in all vertical shafts are summed to the estimated to determine the volume flow into the pumping station.

Since the pump of the pumping station is used to carry out the conventional operation with the channel at open level the level near the bottom of the underground Channel is arranged, the pressure head between the Water level of a water tank on the conveyor and the lowest water level LWL large. That is why the Ge Velocity of the pump large, so that the installation cost of the pumping station including pumps and supplies engine are high. Since the water level of the under earthly channel is also kept low Storage effect low. The water level will drop soon, causing the pump to stop. Then the water returns to his Level back in a short time, so that the pump again starts, which often leads to a commute.

Because the underground channel, which is a length of several Kilometers, has a large diameter the cost of excavating the underground canal high, what a larger share of the installation costs the water arranged at great depth laxative is responsible. Because the pump in large Soil depth must be installed are the excavation costs also great for the pumping station.

When operating the channel with closed current is on the other hand, the water level of the underground canal higher compared to the duct operation with open  Level. Therefore the total pressure level of the pump is low, thereby reducing the installation cost of the pumping station finally the pumps and prime mover lower are. However, there is a greater likelihood that water from the vertical shafts to the floor surface overflows.

Regarding the conventional flow factor for estimation the inflow amount was not taken into account that if the period between rainfall is short, the Rainwater hardly penetrates into the ground, but into it Water drainage system flows and the inflow increases. This makes the accuracy of the estimated amount of electricity in the vertical shafts regarding a change in the Period between rainfall is small. Therefore it can possible that the pumping station is not working properly, so that the water overflows from the vertical shafts can.

The object underlying the invention is therefore in it, one arranged at great depth To create drainage systems that deal with low Manufacture costs and operate in a stable manner.

This goal is based on the at great depth arranged water drainage system with an underground water channel with a large capacity, which in arranged at great depth and slightly inclined, with ver tical shafts to guide the draining water down in the underground canal from in the ground floor Surface or near the surface provided flood protection channels, with a pump shaft, which on provided downstream end of the underground channel and with a pumping station with a pump, through  which flows the water that has flowed into the pump shaft or pumped to the sea according to a first solution thereby achieved that an impeller of the pump in the pump overall station at an average water level of the un terrestrial channel is arranged and that the pump has such characteristics that it draws water from the full Channel, d. H. with closed water level with a Nominal flow rate, but also from the duct when the Can pump water level with a minimum flow.

Starting from the same generic system lets according to a second solution achieve an impeller of the pump in the pumping station overall at an average water level of the underground cal channel is arranged that the pump the water out the full channel, d. H. with closed water level, with a nominal volume flow, but also from the duct at offe Pump water level with a minimal flow can and that the maximum efficiency at a Volume flow reached between the volume flows at a channel operation with closed and with open Level lies.

Based on the generic system that can thereby achieve the mentioned goal according to a third solution Chen that an impeller of the pump in the pumping station overall at an average water level of the underground Channel is arranged and that the pump with such variable slope or division is built that they Water from the canal with the water level closed a nominal volume flow, but also from the duct at offe pump water level with a minimum flow.  

The stated goal can be based on the genus system according to a fourth solution Chen that an impeller of the pump in the pump station overall at an average water level of the underground cal channel is arranged and that the pump has two stages is formed and a first impeller with an overall pressure level at which the water from the channel at closed duct flow pumped with the nominal flow rate can be, and a second impeller with a total pressure level at which the water from the channel at open channel flow with a minimum flow rate ge can be pumped.

The invention also includes a method for operating the water drainage system arranged at great depth, at which in flood protection channels in the upper floor surface or near the surface of the floor Water through vertical shafts down into one underground water channel with large capacity is flowing down a great depth and which is slightly inclined, and the draining Water flowing into a pump shaft on the downstream side End of the underground channel flows into rivers or into the sea through one arranged in a pumping station Pump is pumped, and which is characterized by that a mixed operation with closed channel flow and open channel current is carried out, in which the Pump is operated with a flow rate that is greater than the volume flow of the flowing water, which in the pumping station in the closed state Channel current flows in which the underground channel is completely filled with water, and at which the Pump is operated with a flow rate that is smaller than the flow of water flowing into the  Pump station in the state with open channel current flows in which is the water level in the underground channel is lowered.

In a further solution to the problem mentioned starting from the system of the generic type Pump placed underground at a level that at least higher than the top of the underground Channel lies, and a large volume pump container provided between the pump shaft and the pump, wherein the bottom of the pump container overall on the same Level as the pump is arranged.

For the drainage arranged at a great depth plant, which is designed generically, in Important in terms of minimizing construction costs be that if a construction site for the pumping station it is difficult to provide the system chosen is that the pump is on an overall average Water level is located in the underground channel, and that if the site is easy to deploy, the System is chosen so that the pump on a Level is at least higher than an upper end of the underground channel, and that between the Pump shaft and the pump with a pump storage tank large volume is provided.

The water drainage system arranged at great depth can be operated according to the invention in such a way that a precipitation information a precipitation amount is calculated that the mass flow into the vertical Channels according to the amount of precipitation and a Ab flow factor can be calculated from an interval between a precipitation pattern and a subsequent one  rain pattern is determined that the quantities flow into the pumping station according to the volume flow in the vertical shafts is calculated and that the number of pumps that are to be put into operation, as well as their Power according to the flow into the pumping station is determined to drain water from the pumping station.

The pump of the pumping station is overall on the middle Water level of the underground canal arranged, whereby the operation can be carried out for the open channel. The nominal flow rate of the pump is at the total pressure height he with the high water level in canal operation with ge closed level at which the underground Channel is completely filled with water. At this Arrangement, the total pressure head is smaller than that conventional structure, in which the water from a low water level of an underground canal a nominal volume flow in a company for one channel is pumped with an open level. As a result, the In Installation costs for the pumps and the drive machine reduced, as well as that required for pumping Power consumption. Because the pump on the middle water level of the underground channel is a Space in the underground channel above this middle one Level available. The memory effect of the long under earthly channel reduces the risk regarding the Rise in water level. Therefore the diameter of the underground canal are reduced, which the Excavation costs for the underground canal reduced.

The properties and characteristics of the pump are like this determined that the pump has the total pressure head at which is pumping out of the channel with the channel closed current with nominal flow is possible, but also  has the total head at which the pumping from the Duct with an open duct flow with a minimal volume flow is possible. With this arrangement, the operation at a full channel, i.e. when operating with a closed one nem channel current in which the water at the low Total pressure head can be pumped with the nominal flow and operation in a channel with an open level or when operating with open channel current, in which the Water at a high pressure level with the minimum quantities current must be pumped by the same pump become. This prevents an increase in install the number of pumps.

The pump efficiency is set so that it at the Flow between the flow for the closed duct operation and the volume flow for the open Channel operation has a maximum effect. With this arrangement you can the cost of the pumps and the prime mover for the mixed operation of open channel flow and closed Channel current can be reduced.

If the slope of the blades of the pump is changeable the pump has a total pressure head at of the water from the full channel with nominal quantities can pump electricity, but also a Ge total pressure at which the pump takes the water out of the sewer Pump with open water level with minimal flow can. Because of this arrangement, one and the same Pump for both the closed duct current state and can also be used for the open channel current state, so the number of pumps does not get increased needs.  

If the pump has a two-stage impeller, the impeller is to the total pressure head at which the water from the Channel with closed water level with nominal flow can be pumped and adapted to the total pressure level, where the water comes from the canal with open water level can be pumped at the minimum flow rate. With this arrangement, one and the same pump can both in the closed channel state as well as in the open channel condition used so that the number of pumps does not need to be increased.

In mixed operation with closed and open channel the pump is in the state with the nominal flow rate with closed flow of the underground channel and with the minimum volume flow in the state of the open flow operated in the underground channel. Regardless of the condition of the underground canal in this mode of operation the water drainage system arranged at great depth operated stably.

The large capacity pump tank is between the Pump shaft and the pump at great depth orderly drainage system provided to the operation of the channel with a closed current. Because of The storage effect of this pump container is the danger of overflowing from the underground channel to the ground limited surface and the diameter of the bottom earthly channel can be reduced. As a result of Storage effect of the pump tank can also in Water drainage system arranged at a great depth is stable operated in the state of the channel with closed current become.  

When a construction site is difficult for the pumping station is to be delivered, select the mixed operating system with open and closed sewer flow that does not have a pump tank with a large capacity. If the construction area readily available for the large capacity pump tank can be set, you select the operating system with closed channel flow, which is a small pump head or head required. This way you can the water drainage system arranged at great depth be chosen, the construction costs are minimal.

A precipitation pattern usually looks like that Precipitation increases with time, a peak reached and then goes back to zero. The degree of penetration of rainwater in the soil changes depending on a period between a precipitation and a subsequent precipitation. If this time interval is short, the rainwater hardly penetrates into the ground, but flows into the vertical to an increased extent Manholes. With the outflow factor, which is determined by the time interval vall is determined between the precipitation patterns, the amount of precipitation is calculated, the amount current in the vertical shafts, resulting in a exact estimate of what is entering the pumping station Flow is possible. With this procedure the Operation of the pump station controlled in a suitable manner be so that the arranged at great depth Water drainage system can work stably.

The above described arranged in great depth nete water drainage system, which in mixed operation with open and can work with closed channel current following beneficial effects:  

A. The overall pump head is noticeably reduced, this also applies to the installation costs of the Pump station including the cost of the pumps and the prime mover.

B. The excavation costs for the underground sewer are decreased.

C. Due to the storage effect of the very long under earthly channel becomes the danger of overflowing restricted to the floor surface.

D. The memory effect mentioned eliminates the necessary for a pump container with a large capacity to like. The pump station can therefore be in the middle of the City to be built, so in an area where there is it is difficult to acquire property.

In the present invention, the on position of the pump in the central section of the underground channel seen in its height direction. Due to the possible mixed operation between open and closed duct flow can be the total pressure level of the Pump can be reduced, which is the installation cost for the pump decreased. It also reduces the memory effect of the long underground channel the danger of Water level rise. Therefore, the diameter of the underground canal can be reduced, thereby reducing the Excavation costs for the canal become lower.

By using the for mixed operation with open and suitable pump types the installation costs for the pumps and the Also reduce the engine.  

If a pump container with a large capacity between between the pump shaft and the pump, decreases when the channel is closed current the danger of overflowing to the ground surface from underground channel because of the storage effect of this pump container, whereby the diameter of the underground channel can be further reduced.

Because the provision of building ground for the pumping station is difficult, you choose the mixing system with open and closed channel flow, for which a pump container with large capacity is not required. If however, inexpensive building site for the pump container with large Capacity can be provided, that will Closed channel flow system used so that one can choose a lower pump head. With this Measure can be arranged at a great depth Select water drainage system, the minimum construction costs required.

Furthermore, it is possible to arrange the at great depth nete water drainage system to operate stably by a Precipitation amount calculated with an outflow factor which corresponds to an interval between one Precipitation pattern and a subsequent low beat pattern is changed to a rainfall to determine which flows into the vertical shafts, which causes the amount of rain falling into the pumping station flows, is accurately predicted and the operation of the Control pump station accordingly.

Exemplary embodiments of the Invention explained in more detail. Show it:  

Fig. 1 in perspective the basic construction of which is arranged at a great depth Wasserabführanlage,

Fig. 2 shows schematically an embodiment of the plant for a mixed mode with open and closed channel current,

Fig. 3A and 3B schematically illustrates the water level at which the pump starts in mixed operation with open channel and closed flow channel current,

Fig. 4 a diagram showing characteristic curves for the mixed operation with open and closed channel current depends on the pressure head and the flow rate,

Fig. 5 in a graph as Fig. 4 curves depending on the total pressure head and delivery rate,

Fig. 6 schematically shows an embodiment of the system for operation with a closed channel current,

7 schematically shows an arrangement for accurately estimating and controlling the amount of current tion. In a Pumpsta,

Fig. 8 is an operational flow diagram for an execution form of the plant from the precipitate to the discharge by the pump,

Fig. 9 a graph showing the relationship between time and rainfall as well as the relationship between time and amount of inflow to the plant,

Fig. 10 is an operational flowchart of the Wasserabführsy stems for detecting a sudden schwemmungsflut and time to estimate their arrival,

Fig. 11 is a view of the overall construction of another embodiment of Wasserabführanlage,

Fig. 12 shows an embodiment of the underground water stacking system in longitudinal section;

Fig. 13 in longitudinal section, a movable weir serves as a movable Mengenstromeinstelleinrichtung shown in FIG. 12,

Fig. 14 in a longitudinal section a valve which serves as bewegli che Mengenstromeinstelleinrichtung shown in FIG. 12,

Fig. 15 is a block diagram of the Mengenstromeinstelleinrich obligations to determine the optimum amount of current from rivers or flood protection channels and for adjusting the amount of current to a value len optima,

16 shows a further embodiment of the plant in which a movable weir in an underground delivery channel is disposed upstream of a pump station Fig., In longitudinal section,

Fig. 17, in a longitudinal section of a modification of the embodiment of FIG. 12

Fig. 18 a diagram showing the speed increase of the water level of the pump well of the plant,

Fig. 19 position in a diagram, a pump start-up pattern of the An, the results when the Steiggeschwindig ness of the water level in the pump shaft is large,

Fig. 20 in a diagram a pump start-up pattern of the plant, which is obtained when the Climb Speed speed of the water level in the pump well is low,

Fig. 21 in longitudinal section a part of the pumping station from Fig. 12,

Fig. 22 shows a detail of the part of the pumping station from Fig. 21,

FIGS. 23 and 24 are longitudinal sections showing embodiments of a pump arrangement of the embodiment of Fig. 12 show

Figure 25 in cross-section an embodiment of a pump. Dung used according OF INVENTION

Fig. 26 shows the section XXVI-XXVI of Fig. 25 and

Fig. 27 shows the section XXVII-XXVII of Fig. 25.

The water drainage system shown in Fig. 1 has an underground water channel 1 , which is slightly inclined and is provided in the ground at great depth. Rainwater and the like flow from flood protection ducts 3 and lines 4 into the underground duct 1 through vertical shafts 2 . A downstream end of the underground channel 1 is connected to a pump station. The water flowing into the pump station is conveyed to rivers by a pump 7 or by pumps 7 .

The embodiment of the system shown in Fig. 2, which is used to carry out a mixed operation with open and closed channel flow, shows the underground water channel 1 with a large bore diameter of not less than 10 m, which is at great depth, for example at least 50 m from the ground surface, is arranged so that buildings on the ground surface are not affected by the formation of the underground channel 1 . In the underground channel 1 , rainwater and the like flows from an overflow protection channel 3 , a line 4 , rivers 5 , etc. via vertical shafts 2 . A downstream end of the underground duct 1 is connected to a pump shaft 6 of a pump station. The water flowing into the pump shaft 6 is conveyed to a water reservoir 8 by a pump 7 .

In conventional operation with an open channel flow, the level at which the pump is arranged is overall at the level of the bottom of the underground channel 1 . For operation with an open channel flow according to the embodiment shown in FIG. 2, however, the pump 7 is arranged overall at a mean water level of the underground channel 1 , so that the lowest water level LWL, which allows drainage, is the central water level of the underground channel 1 . If the mixed operation for the open and closed sewer flow has the operating state with open sewer flow, the water level of the underground duct 1 is kept at the lowest water level LWL, so that the underground duct is an open duct flow channel 1 , which has a free space above the water level of the underground channel 1 . In operation with a closed channel flow, the underground channel 1 is filled with water so that it is full and forms a closed channel, whereby the water can rise to a level which is higher than a lowermost section of the vertical shaft 2 .

In the following the total pressure level or total för the height H of the pump in mixed operation with open and described closed channel current. The total pressure level H is a total value that can be obtained by adding one Delivery line loss to the actual pump pressure level Ha results. It can be expressed by H = sum of actual pump head Ha (water level of the discharge water tank minus water level WL at the time of Pump start) plus discharge line loss.

If, for example, the actual pump pressure height Ha and the delivery line loss are 57 m and 3.5 m, as illustrated by the solid line in FIG. 4, the overall pressure height H is 60.5 m = 57 m +3.5 m.

In conventional operation with open channel flow, the design is such that one has a nominal flow rate at a total head H at which the water can be pumped from the lowest water level LWL, which is illustrated in Fig. 4 by a broken line. In the case of mixed operation with open and closed sewer flow, however, the discharge must be effected with a nominal flow in the closed / open sewer state, in which the water fills the underground sewer 1 and continues to rise in the vertical shafts 2 . If the actual pump pressure head Ha from the highest water level HWL is 35.5 m, as shown in FIG. 3A, the total pressure head H below results, in which case the delivery line loss has the same value of 3.5 m.

39.0 m = 35.5 m + 3.5 m.

Therefore it follows from 39.0 / 60.5 = 0.644 that the Ge total pressure height H is reduced to 64.4%.

If in mixed operation with open and closed sewer flow the operating state with open sewer flow is given, the water level at which the pump starts is the lowest water level LWL. Therefore, the actual pump head Ha increases as shown in Fig. 3B. However, the water level is low, so this risk is low. Therefore the nominal flow rate is not required. The pump only needs to be operated with the flow rate that is achieved with the total pressure head H at this time.

If the diameter of the pipe or pipe of the underground channel 1 is 10 m and if the water level (the lowest water level LWL) at which the pump 7 starts is a level of 30% to 90% of the pipe diameter, the mounting position can the pump is 3 to 9 m above the level used in a conven- union drainage system, which can reduce excavation costs.

In this embodiment, the water level thus rises WL, at which the pump with the nominal flow runs, from the lowest water level LWL, as in the conventional system was used at the highest Water level HWL. Therefore, the performance of the pump, the output of a diesel engine for the drive the pump and thus the fuel consumption is reduced become.

The underground channel 1 extends over a long distance. It can therefore temporarily store a large volume of water. The underground channel 1 has, for example, a pipe diameter of 10 m, a length of 10 km and a capacity of about 400,000 m ³ and a storage time of about 30 minutes for the pump with an output of 200 m ³ / s. The time capacity enables the pump 7 to be installed at a higher level. Due to a reduced risk with respect to the increase in the water level, the pipe diameter of the underground channel 1 , which is 12.5 m according to the prior art, can be reduced to 10 m. The reduced pipe diameter of the underground channel 1 leads to a reduction in the excavation costs for the underground channel 1 , which is responsible for a large part of the installation costs of a water drainage system arranged in the deep ground. In addition, the mentioned storage effect prevents oscillation or oscillation, which results from frequent starting and stopping of the pump 7 .

An embodiment of a pump, which is suitable for mixed operation with open and closed channel flow, has total pressure head-H delivery quantity-Q characteristic curves, which are shown in full in FIG. 5. These characteristic curves enable a total pressure head A at which pumping from the highest water level HWL at 100% of the nominal flow rate in operation with a closed duct flow is achievable, as well as a total pressure head B at which pumping from the duct with an open water level at a minimum flow rate , namely 40% of the nominal volume flow, is possible. With this arrangement, both the operation with closed channel flow, in which the pumping with a smaller total pressure head must be effected at the nominal flow rate, and the operation with open channel flow, in which the pumping with the larger total pressure head with the minimum flow rate is effected from one and the same pump, so that the number of pumps to be installed can be reduced.

A pump for conventional operation with an open channel flow is designed so that the maximum efficiency is achieved at a total pressure head c at which pumping from the lowest water level LWL is possible at a nominal flow rate, which is shown in Fig. 5 by a dashed line Line is shown. In the inventive design according to the invention, however, the efficiency of the pump is determined so that a maximum at a gene flow rate, for example 80% of the maximum flow, between the for operation with a closed channel flow and for operation with an open channel flow is a maxi mum. With this arrangement, the cost of the pump and the prime mover for performing the mixed operation with open and closed duct flow can be reduced.

The pump mentioned can be built so that the slope the blades is variable so that the total head  is provided in which the pumping from the channel with closed water level at the nominal flow rate can be prepared, as well as the total pressure level is in which the pumping from the channel with open Water level carried out at the minimum flow rate can be. With this arrangement, both the Operation with closed duct current as well as with open Sewer flow using the same pump run what the number of installed Pumps reduced.

The pump mentioned can also be a pump with a Be a two-stage impeller. The impellers correspond to each the total pressure head at which the pumping out of the duct with closed water level at nominal flow rate can be performed while the total pressure at which the Pumping from the sewer with open water level is done with the minimum flow can be effected. At this Arrangement can both operate with the closed Channel current as well as the operation with open channel current run with one and the same pump, whereby the number of pumps to be installed can be reduced can. Thus, the mixed operation with open and ge closed channel used, when the under earthly channel is full, the pump with nominal flow or is operated with a mass flow that is larger than the volume flow of water into the pumping station. If the underground channel is open, the pump is driven with minimal flow or with a mass flow that is smaller than the quantities stream of water into the pumping station. With this ver can drive regardless of the condition of the underground Channel the drainage arranged at a great depth system running stable.  

As shown in FIG. 6, a large-capacity pumping container 9 is provided between a pumping shaft 6 and a pump of the sewage discharge system arranged at a great depth to operate with the sewer flow closed. The storage effect of this pump container reduces the risk that water from the underground channel 1 overflows to the ground surface. Therefore, the diameter of the subterranean channel 1 can be reduced. The storage effect of the pump container 9 with a large capacity also makes it possible to let the water drainage system arranged at a great depth work stably in operation with a closed sewer flow.

If it is difficult to provide sufficient space or reason for the construction of a pumping station, one selects the operating system with closed and open channel flow, in which a pump container 9 with a large capacity is not required. However, if there is sufficient space for the construction of the pump station, choose the operating system with closed channel flow, which requires a lower pump pressure level. This allows the water drainage system to be built at a great depth with a minimum of cost.

So that the temporary storage effect mentioned in the below earthly channel can be used effectively, the Flow rate to the pumping station is precisely estimated and ge be controlled to the water drainage system accordingly the volume flow entering the pumping station is stable to be able to run. If this requirement is not is enough, the water flows out of the vertical chess ten and the pump shaft.  

As can be seen from FIG. 7, the amount of precipitation is estimated in accordance with the data of a precipitation radar 10 . The precipitation data are compiled from pluviometers (rain gauges) that are positioned at specified points. The amount of rainwater that does not penetrate the soil, but flows into the vertical shafts 2 , is calculated by analyzing the estimated amount of precipitation and the precipitation data, from which an outflow amount is determined. The amounts of the flows in the vertical shafts 2 are added up and the flow in the underground channel 1 is analyzed. The volume flow and the water level in the underground channel 1 are calculated on this basis. The mass flow arriving in the pump shaft 6 is analyzed on the basis of the mass flow in the underground channel 1 , from which the mass flow into the pump shaft 6 and the water level therein are calculated. The pump operation is simulated on the basis of the volume flow entering the pump shaft 6 and the water level present therein, in order to determine the number of pumps to be put into operation, the delivery volume of the pump and the timing for starting and stopping the pump or pumps. The pumps are controlled on this basis. At the same time, this data is fed back to the analysis step for the water flow in the underground channel 1 .

Another method for accurately estimating the flow into the pumping station is shown with reference to FIGS. 8 and 9. The volume flow into the vertical shafts is estimated according to precipitation data or in response to a change in time.

If rain falls in a district to be drained, a temporally changing amount of precipitation is determined in a step 1 on the basis of precipitation information, for example on the basis of a value in mm / h. Since the degree of penetration of the water into the soil changes strongly depending on a time interval ΔT between the precipitation and a subsequent precipitation, the volume flow in the vertical shafts also changes, which requires a change in the outflow factor in accordance with a precipitation pattern. For example, according to ΔT in FIG. 9, the outflow factor changes in the range between 0.3 and 0.9. In a step 2, the mass flow into the vertical shafts is determined from this outflow factor and the amount of precipitation. In a step 3, the volume flow into the pumping station is determined from the volume flow into the vertical shafts, using a means for estimating the volume flow entering the pumping station. In a step 4, a quantity or delivery quantity discharged from the pump, ie the number of pumps to be put into operation and the delivery quantity, is determined from the quantity flow thus obtained into the pumping station and a pump operating method. The change pattern of the precipitation is shifted to the current pattern in the vertical wells and then to the current pattern in the pumping station as shown in FIG. 9. In this way, the aforementioned estimation or determination is carried out, the changes mentioned being taken into account.

According to the precipitation pattern, the Precipitation over time to a peak and then decreases down to 0 over time. The degree of penetration of rainwater This in the ground changes over time  interval between a precipitation and one on it following precipitation. For example, if that's time interval is short, the rainwater hardly penetrates the Floor, but flows in large quantities into the ver tical shafts. The outflow factor changes accordingly according to the time interval between two successive the precipitation patterns. The rainfall is calculated using this outflow factor. Of the Volume flow in the vertical shaft is never the impact amount is calculated. Then the in the The flow rate entering the pumping station is precisely estimated. At the operation of the pumping station can do exactly this be controlled so that the arranged at great depth Water drainage system can work stably.

Below are examples of ways to estimate of the volume flow to the pumping stations:

• 1. Estimation options from a physical Depend on simulation.
• 2. Estimation options that result from a change in the Water level in the vertical shaft on a stro depending on the area.
• 3. Estimation options from finding one Flooding at an upstream point hang.
• 4. Estimation options that depend on nerves and have a learning function.

With reference to FIGS. 10 and 11, the drainage will now be described including the estimation options that depend on the detection of a flood at an upstream location.

In the water drainage system shown in Fig. 11, a water drainage pumping station 11 is arranged near a river to which the water to be discharged is conveyed. This water to be discharged, for example rain water, is collected in an underground channel 1 , which is provided in the area to be drained. The water is introduced into the pumping station 11 and then pumped into rivers. The underground channel 1 has a main line 12 and a plurality of branch lines 13-1 (i = 1 to 4 in the drawings). Referring to FIG. 11, the pumping station 11 has a pump shaft (not shown) for storing water that enters from the main line 12, and pump 7 for pumping the water from the pump shaft into rivers and a pump control means 14 for controlling the operation of the pumps 7 .

At an upstream point a of the branch line 13- 1, a water level detector 15 a is arranged. At one point of the branch line b 13-1 is provided downstream from the point A, a further water level detector 15 b. A water level detector 15 e is located at an upstream point e of the branch line 13-2 . At a point f of the branch line 13-2 downstream from the point e, a water level detector 15 f is arranged. The water level detectors 15 a, 15 b, 15 e and 15 f determine the water level in the branch lines and can be carried out in a conventional manner, for example as a capacitive or ultrasonic measuring device. The value for the water level at the points mentioned, which is determined by the water level detectors 15 , is transmitted from the pump control device 14 via a communication system, not shown. Although no other water level detectors are arranged in the other branch lines 13-3 and 13-4 , such detectors can be installed there if necessary. It is only necessary to measure a flood with a large volume flow, which is expected to arrive soon at the pumping station 11 , and to determine its arrival time. With respect to the total of this embodiment of Wasserabführsystems and the geographical construction of be dewatered range, the water level detectors 15 are arranged lines at the branch, which cover a large area of about ent watering district, and are closer to the pumping station 11 is arranged, whereby the flooding is detected.

In the water drainage system of this construction, the discharge capacity, ie the number of pumps P ₁ , P ₂ and P ₃ to be put into operation, and the speed of the pumps are automatically controlled by the pump control device 14 accordingly, the water level in the pumping station 11 , whereby the Leakage flow is set. The pumps are also automatically controlled according to the information provided by conventional flow rate estimators entering the pumping station.

Referring to FIG. 10, the determination of flooding and the estimation of the arrival time is carried of flooding at the pumping station via the pump control device 14 in accordance with the water level data, the detectors the Wasserpegelde 15 a, 15 b, 15 e and deliver 15 f. The pump control device 14 has a computer which receives the water level data from the water level detectors 15 a, 15 b, 15 e and 15 f at predetermined measuring intervals and processes the input signals in the usual way and stores this data in a data storage table. The pump control device 14 reads the water level data thus stored from the memory in a suitable manner and executes the process according to FIG. 10.

In this process, flooding is to take place in the branch line 13-1 . The same process is to take place in branch line 13-2 , but it is sufficient if the explanation follows only with reference to branch line 13-1 . The occurrence of the flood in the form of a downward flow is determined in steps 31 and 32 . In the event of flooding, the water level pattern changes so that the water level rises abruptly. In the embodiment described, a value ha (t) is taken for the water level at the upstream point a. Then the difference between this reading and a water level reading ha (t-1) that resulted in a previous cycle is calculated using equation (1) below, thereby obtaining an incremental value Δha (t) for the water level (step 31) receives.

Δha (t) = ha (t) - ha (t + 1) (1).

It is then estimated in a step 32 whether the Increment value Δha (t) greater than a predetermined value k, is a flood estimate reference value, or this value is the same or not. If this estimate is negative, d. H. If "NO", the process goes back to step 31. The same process is repeated with respect to the following data. If instead the estimate is confirmed is done, d. H. "YES" is a maximum water level hm determined for the flooding in step 33. For the effect of this finding will be a change in the  Water level reading ha (t) in the above data table le monitors and there is a measured value for a maximum value specified as the maximum water level. At the time point of measurement of the maximum water level becomes a Timers turned on and the time measured until the Flooding arrives at the downstream point b - Step 34. When the flood is detected, an alarm is given in response to this measurement signal. The Occurrence of flooding and the place of occurrence the flooding can also be on a display device, For example, a graphic board can be displayed. The Flooding cannot be caused only by the water mentioned level increment value, but also determined thereby be that the water level is a predetermined one Value exceeds or that the turbidity of the to be discharged Water becomes abnormally high. The subsequent steps 35 to 43 serve to find a correction factor a in order to the arrival time of the flood by a calculation taking hydraulic laws into account estimate. Various estimates can be made to estimate the time of arrival methods are used that are based on conventional based on hydraulic models. In the present Embodiment, however, is in view of the for Time required to process the estimate Special procedure depending on a hydraulic flood wave model applied. The rate of progress ω, d. H. the flow rate of the flooding in this tidal wave model by the following Glei chung (2) specified. This model applies to one line with a rectangular cross section. The model can however also for a line with a circular cross section used when the variables are appropriate be modified.  

ho is an initial water level at the front end of the over flooding, V is an initial flow velocity at Initial water level ho and g is the acceleration due to gravity. The initial flow velocity V results from the Equation (3).

N is a roughness coefficient of the line and I a line gradient. If the flow rate ω is determined, the arrival time is at one downstream point in the same water drain pipe by this distance up to this downstream point is divided by ω.

According to the hydraulic theory above, an An results initial velocity Va at point a by the equation (3) in step 35. In step 36 then the flow velocity ωa determined according to equation (2). in the Step 37 is then an estimate T'ab for the Arrival time at point b at a distance Lab from point a to the equation (4) calculated.

T′ab = Lab / ωa. (4)

In the following steps 38 to 40, the Flooding and a maximum water level hm at point b detected. This is the same as for the Steps 31 through 33 so that further explanation can be omitted. At the time of the arrival of the  maximum water level of the flood at point b in Step 40 is determined, the mentioned timer stopped - step 41. A measured value tab for the Time - step 42 - determines the time required until the flooding at point b starting from point a arrives. In step 43 the correction factor is then α calculated for the estimated time according to equation (5).

α = T'ab / Tab (5).

Since the measured value is usually larger than that theoretically is certain value, α 1.0 is provided.

Then an estimated time T'bd, which is the Flood from point B to pumping point d tigt, calculated according to equation (6).

T′Jbd = α (T′bc + T′cd) (6).

T'bc and T'cd in this equation are determined based on equations (2), (3) and (4). Since the main line 12 differs from the branch line 13-1 with regard to the line sizes, for example the line diameter, the initial water level ho and the maximum water level hm are determined on the basis of the measured values at point h via proportional calculation. In this case, to estimate the initial water level ho, the mass flow of the water to be discharged to the connection point c from the other branch lines 13-2 , 13-3 and 13-4 is taken into account. For this purpose, a water level detector is arranged at the connection point c in order to determine the initial water level ho. However, if the flooding in the branch line 13-1 first arrives at the connection point c, the flow rate from the other branch lines to the connection point c does not differ from the normal flow rate at this time. Therefore, a correlation coefficient based on actual data for the flow rate ratio of the branch lines from the past is created beforehand. The initial water level at junction c is then determined by multiplying the initial water level at point a by this correlation coefficient. This method is used in the present embodiment. It is only necessary to estimate the arrival time of the flood, which is expected to be the first to arrive at the drainage pumping point. Therefore, if a flood in the branch line 13-2 arrives at the junction c first, that is, earlier than a flood in the branch line 13-1 , the arrival time T'fd is estimated with reference to the flood in the branch line 13-2 .

On the basis of the arrival time T′bd so determined in step 45 the number of those to be put into operation Drainage pumps and the time for the start of the pump operation. Also dependent on this A previous standby mode is set for controlled the flooding. Usually a lot is provided by water drainage pumps, the Number of pumps to be commissioned depending on determine the magnitude of the flood.

As described above, in this embodiment shape the water level of the water drainage channel at the stream overlying point a measured and estimated whether the Increment value of which is abrupt or not, causing the Existence of a flood can be determined quickly. At This procedure can start up the water  laxative pumps as a countermeasure in good time become. Based on the degree, i.e. H. the water level or the increment value, the flooding, the distance from that Measuring point of the flooding up to the water drainage pumping point and the influencing variables of the water discharge channel can be the time until the flooding arrives at the water discharge pumping station according to the hydraulic theory estimate or calculate. This allows commissioning of the drainage pumps as a countermeasure in good time be effected.

In accordance with these estimation results will be the number to be put into operation in advance Pumping both determines the time for their start. Thereby the incoming tidal wave or flooding easy to handle.

The time during which the previous standby operation the water drainage pumps can be carried out limited by a cooling system for the bearings of the pumps. The time for the previous standby mode can can be optimized by the above estimate so that a Damage to the pump bearings can be prevented. When Possibilities for controlling the volume flow in the vertical shafts into the pump station The quantity flow introduced can serve:

• 1) Control of the volume flow in the vertical Shafts in from a variety of water discharge channels.
• 2) Control of the volume flow into the pumping station through a mobile weir.  
• 3) Drainage from the open channel / closed Channel.
• 4) Control a variety of stations in total manner.
• 5) Controlling the volume flow at the conveyor (delivery) - Side of the pump through an overflow weir.

To control the flow rate from a plurality of water discharge channels into the vertical shafts in the underground water drainage system according to FIG. 12, movable flow rate adjustment devices 16 are arranged, which are each arranged in flow channels that lead from rivers and flood control channels to the respective vertical shafts 2 . In this arrangement, the mass flow in the underground channel 1 from the rivers and the flood regulation channels is set. The flow rates from the respective rivers and flood control channels into the vertical shafts 2 can be adjusted independently of one another in accordance with the water level or the flow rate of the rivers and the flood control channels.

To control the amounts introduced into the pump station flow through the movable weir is shown in Fig. 13 an arrangement in which the movable Mengenstromeinstellvor direction (16 in Fig. 12) is formed by a movable weir 17th The movable weir 17 is vertically movable bar so that its height can be adjusted. The movable weir 17 can also be carried out in swivel design. For a large size system, however, the movable weir as shown in Fig. 13 is preferred because the control power is small and foreign matter is less likely to be caught by the weir.

In the arrangement of FIG. 14, the vertical shafts 2 of rivers and flood control channels from leading flow channels are each formed by conduits. The volume flow setting device ( 16 in FIG. 12) is formed by a valve 16 . A valve 16 in the form of a throttle valve is preferred, which allows the flow rate to be set and which can be manufactured with a relatively large dimension.

For the operation of the underground water drainage system of the construction described above, an optimal quantity flow (inflow speed) from the rivers and flood control channels is determined in accordance with the operating state of the pumps 7 , the water level of the underground channel 1 , the total inflow rate or the estimated inflow rate and the water levels of the rivers and flood control channels sets. The flow rate is set to an optimal value by the flow rate setting devices 16 . If, for example, a large amount of water flows in the respective rivers and flood control channels depending on the weather condition and poses a risk of flooding, these rivers and flood control channels are preferably emptied as far as the operating conditions of the pumps 7 , the water level of the underground channel 1 and the total inflow amount allow. This prevents damage due to flooding and the performance of the water drainage system reaches its maximum.

With the arrangement shown in FIG. 15 as a block diagram, the optimum flow rate from the flows and flood regulation channels can be determined and the flow rate through the flow rate setting devices can be set to an optimal value.

It is assumed that as shown in FIG. 15, the streams A, B and the Überschwemmungsregulierkanäle the lines C of the subterranean Wasserabführanlage be controlled. A control device 18 continuously monitors the water level of the rivers A, the flooding regulation channels B and the lines C, the flow rate Q, the vertical shafts 2 , the water level of the underground channel 1 and the sum Q of the water quantity discharged by the pumps. When the amount of precipitation in the river A basin is large and the water level of this river rises, the operating state of the pumps 7 is confirmed by the water level of the underground channel 1 and the water discharge amount of the pumps 7 . When there is room for the delivery rate of the pumps, a control signal is given to the flow rate setting device 16 to increase the flow rate Qa from the flow A. The control device 18 can be set so that at this time, even if there is no space for the delivery rate of the pumps 7 , although there is space for the delivery amount of the flood control channel B and the line C with respect to the water level, and if the rate of climb of the water level in the river A is so high that there is a risk of flooding, control signals are respectively transmitted to the volume flow adjusting devices 16 for the flood regulation channel B and the line C in order to reduce the volume flows Qb and Qc, during which the volume flow Qa from the River A is increased. This method shows the full functionality of the water drainage system from this embodiment. The reliability of the water drainage system could be increased.

If it is to be expected that these rivers and flood control channels will send a sudden tidal current based on the flows of rainwater from the rivers and the flood control channels or based on their estimated flow rates, water from these rivers and flood control channels will be drained into the underground channel 1 in advance , which reduces the water level to a minimum level that enables the pumps to operate. The pumps are then started to cause the water to drain, causing the water level of the corresponding river or flood control channel to drop to a level near the lowest level. By utilizing the storage effect of the river and the flood regulation channel, the standby run of the pumps can be brought about in preparation for the sudden flood current into underground channel 1 .

At this time, if the pump 7 is a moving vane pump or a variable speed pump and operates to drain water at a low flow rate, the ability of the flow and flood control channel to drain water under the influence of gravity can be maximized be used for an effective standby run.

In the embodiment of FIG. 16, a movable weir 17 is arranged at a location of the underground channel 1 upstream of the pumping station, which prevents dirty water generated in an initial stage of the flow from flowing into the pump shaft 6 , which further increases the operational reliability of the pumps 7 is increased.

In this water drainage system with an open channel, the start of the pump 7 is delayed, for example due to defects in the pump 7 , the movable weir 17 is closed and the storage effect of the underground channel 1 is used to its maximum.

With this structure, the height of the movable weir 17 is adjusted according to the flow rate from the rivers and the flood regulation channels or the flow rate estimated therefrom, thereby stabilizing the water level of the pump shaft 6 . As a result, in particular in the case of a large-sized pump system, the operational reliability of the pumps 7 is increased.

The following is the draining of water from the bottom earthly channel for the open and closed channel current described. In the pump shaft, pumps are mon animals that are able to water in a planned Quantity with closed channel flow of the inflow channel dissipate, and not even in open channel current reach an operating state in which they no longer promote. The pump is a pump with a movable display and causes drainage standby when the blade angle is close to the minimum angle located. According to the increase in the water level in the Pump shaft or the rate of rise of this water level, the blade angle of the pump is adjusted to regulate the discharge flow. The pump can Be a pump with speed control. In this case the Purging standby operation carried out at low speed. Corresponding to the rise in the water level in the pump shaft  or the rate of climb of this water level the speed of the pump for regulating the discharge flow rate set. Alternatively, pumps with high pressure head and low delivery rate, which in the Are able to find a planned amount of water in the open channel drain the underground channel and one Laxative standby operation, as well as pumps with low pressure head and large delivery rate in the Are able to keep a planned amount of water in the closed Discharge sewer current, in combination in the pump shaft to be assembled. A is on the delivery side of the pump Valve superfluous, instead of this can convey an overflow weir or a siphon is provided to control the mass flow.

To the plant arranged at great depth, d. H. the To be able to let the pump station work stably the following measures are taken:

• 1) Purging standby mode by adjusting the pump vane angle and the speed of the pump.
• 2) Previous standby operation of the pump.
• 3) Combination of pumps with high pressure head and small flow rate and pumps with low low pressure and large delivery rate.
• 4) Use of a priority purging algorithm.
• 5) Correct the pump on-off water level according to the rate of climb and descent of the Water level in the pump shaft.  
• 6) One near the pumps for a pass of storage and a bias current provided Reservoir to prevent the pumping effect.

The standby purge mode by adjusting the pump vane angle and the speed of the pumps is in explained above in detail. This procedure is also effective for stable operation of the pumping station.

The previous standby operation of the pumps takes place in such a way that according to the estimated, in the pump shaft introduced volume flow the valve in a delivery channel is opened, as well as the inflow water the pump shaft reached, whereby the pumps are started.

As shown in FIG. 17, a valve 21 is provided in the delivery channel 20 , which connects the storage container 19 to the underground channel 1 . A pump container 22 is arranged at the downstream end of the underground channel 1 . The pumps 7 are immersed in the water in the pump container 22 . From the section on the delivery line 23 , which is located upstream of a delivery valve 24 , a circulation line 25 branches off, which is connected to the underground reservoir 19 . A valve 21-2 is provided in the circulation line 25 . In the event of rain, the mass flow going into the pump container 22 is estimated. Before inflow water reaches the pump container 22 , the valve 21 in the delivery channel 20 is opened in order to supply water from the underground reservoir 19 to the pump container 22 . The water thus conveyed reaches the pump container 22 a certain time later, so that the water level of the pump container 22 rises to a level which permits the pumps 7 to operate, at which point the pumps 7 are started.

When the pumped water flows into the pump container 22 , the standby operation of the pumps is effected before the water flows into the pump container 22 in full.

In the Wasserabführanlage of FIG. 12 is a combina tion is from pumps at high pressure level and low discharge amount, and positioned lower pressure level and a large flow rate. Overall, the lower the underground channel 1, the greater the difference between the lowest water level LWL and the highest water level HWL. If in the underground discharge system the water level of the pump shaft 6 is low, the flow rate or the discharged water quantity can be small, while the discharge speed increases when the water level rises. Therefore, the pumps are shown in FIG. 12 arranged vertically at a distance, ie in multistage ger manner in the vertical direction, each pump is being inserted that it changed för with a predetermined throughput. The pump 7 a with a high pressure head is preferably in the lower stage, while the pump 7 with a low pressure head is arranged in the upper stage. In this case, the pump 7 b with a low pressure level is at a level which is below that of the bottom of the underground reservoir 19 .

With this structure, the difference between the water level of the pump 7 b of the upper stage and the water level of a river (or a sea) 26 , to which the discharged water is conveyed, is reduced and the required pressure level is reduced accordingly. This saves energy that is required for the water drainage process. If the pump 7 b of the upper stage has a low pressure level and a large output, so that the pump can start up in accordance with the rise in the water level, the output for the discharge process is greatly reduced, since the pumping efficiency of the pump is low with a high pressure output and large delivery capacity is large in a wide area. If the water level of the pump shaft 6 is low, it is not necessary to drain water quickly. Therefore, the pump 7 a of the lower stage need only have a small delivery rate, although it has a large pressure head.

Because the multitude of pumps pulling off the water is arranged at least two stages, for the Pump station area or area required Building can be reduced. As a result, the Excavation work, resulting in an increase in construction costs binds.

18 and 19, the correction of the water level for turning on and off the pump according to the rising and falling speed of the water level will now be explained in the pump shaft with reference to FIGS.. Here, FIG. 18 shows the rising rate of the water level in the pump shaft. The solid line illustrates a high rate of rise of the water level, the dashed lines a normal rate of climb of the water level, while the dash-dotted line means a low rate of rise of the water level. Fig. 19 shows the start-up plan for the pumps in the event that the rate of rise of the water level in the pump shaft is high.

The water level at which the pump starts is lower by an amount B2 than the water level in a conventional construction. The difference between this water level and the water level for the start-up of all pumps - in the present embodiment, three pumps are provided - is A2 and is less than the difference A ₁ , which results for the conventional structure. If the rate of rise of the water level is high, the first pump starts at the low water level. The water level at which all pumps start up is also low. This arrangement easily copes with a sudden rise in the water level.

The start-up plan of Fig. 20 is for a low speed to increase the water level in the pump shaft. The first pump starts at a water level that is an amount B3 higher and stops at a low water level. The difference C3 between the water level for starting and the water level for stopping is larger than C1 in the conventional arrangement, which helps to prevent the swinging around the rated speed.

With reference to FIG. 12, the reservoir for preventing the so-called pumping effect, which is provided in the vicinity of the pumps for the temporary storage, and the pre-flow are now explained. The underground reservoir 19 with a fixed capacity is arranged between the ground surface and the underground channel 1 and in the vicinity of the pumping station, ie on the relatively downstream side of the underground channel 1 . The underground reservoir 19 is connected to the underground channel 1 via a vertical shaft 2 . An open to the underground reservoir 19 of the vertical shaft 2 is provided on the side of the underground reservoir 19 's and is at a level which is higher than the bottom of the underground reservoir 19th The bottom of the underground reservoir 19 is connected to the vertical shaft 2 via the discharge line 20 . The discharge line 20 is provided for opening and closing a valve for opening or closing, for example a slide, which is referred to below as a shut-off valve 21 . The discharge line 20 can be connected directly to the underground channel 1 . A pump 27 is connected to the bottom section of the underground reservoir 19 and can pump storage water from the underground reservoir 19 to the bottom surface. With this arrangement, the storage water can be used effectively for fire-fighting purposes and for sprinkling streets and parks. An upper section of the underground reservoir 19 is open to the atmosphere via a vertical shaft 2 . A public facility, such as a park 28 or a sports field, is provided on the floor surface above the underground reservoir 19 . In a space between the floor area and the underground reservoir 19 , a deep garage 29 can be arranged.

The capacity of the underground reservoir 19 is set to be larger than the amount obtained by subtracting the storage capacity of the underground channel 1 from a required storage capacity, which is determined based on the estimated inflow amount and the conditions of the water drainage system , for example on the discharge capacity of the pumps.

In precipitation, the water level of a river rises 5, thereby increasing the flowing channel 1 in the subterranean amount of water so that the water level in the corresponding subterranean channel 1 of the precipitation increases. If the inflowing water suddenly rises, for example as a result of a local cloudburst, the underground channel 1 is completely filled with water. The water level in the vertical shaft 2 , which depends on the underground reservoir 19 , rises abruptly. Therefore, the water level reaches the level of the inlet of the underground reservoir 19 corresponding to the dynamic water gradient 30 shown in Fig. 18. When the water level reaches this level, the underground reservoir 19 begins to store water so that the sudden rise in the water level is mapped. As a result, a sufficient period of time can be provided from the arrival of the inflow water or the downflow to the pump shaft 6 until the pumps 7 begin to operate. Only when the pumps 7 are put into operation after the water level has reached the level of the inlet of the underground storage 19 is prevented that the inflow water flows backwards into the river 5 , the line 4 and the flood control channel 3 , which too would cause a flood.

Although the total water discharge amount of the pumps 7 is set in accordance with the estimated inflow, it is usually set in accordance with the inflow per unit time. Therefore, by initiating the operation of the pumps 7 after the water level reaches the underground reservoir 19 , the rise in the water level can be suppressed.

To ensure that the total pressure head of the pump redu is adorned and that the pump and its drive in Kom can be used to make room for the Saving pumping station can save besides the one described The following measures must be taken:

• 1) Multi-stage structure of the pump station.
• 2) A pump station arranged in a circle.
• 3) A vertical pumping station.

With reference to Fig. 21, which shows the pumping station 11 of Fig. 12 in longitudinal section, and of Fig. 22, which shows a detail of the arrangement of Fig. 21, the multi-stage pumping station mentioned under 1) with circular arrangement is explained in more detail . The inflowing water, such as rain water, which is collected in the underground channel 1 provided for the district to be drained, flows into the pump shaft 6 . The water that has flowed into the pump shaft 6 is pumped out by a group of water-discharging pumps 7 and discharged to the river 5 via a collecting conveyor line 51 and a discharge channel 52 . The group of water-draining pumps 7 is arranged in two stages, ie the pumps are arranged on two different levels. The pump group includes pumps PL1 to n and pumps PH1 to n if n is a natural number. The water-leaching pump PH is a pump with a low pressure head and a high delivery rate, the water leaching pump PL is a pump with a high pressure head and low delivery rate. The pumps PH and the pumps PL are arranged in a circle in the respective stages. With the pump shaft 6 , a suction line 53 of the pumps PH and a suction line 54 of the pumps PL are connected via corresponding collective suction lines 55 and 56 . Each of the collecting suction lines 53 and 54 is ring-shaped in accordance with the circular arrangement of the pumps. Suction slides 57 and 58 are arranged in the suction lines 53 and 54 of the pumps, respectively. The collecting conveyor line 51 is arranged vertically in the middle of the group of pumps 7 . Delivery lines 59 and 60 of the pumps PH and PL are connected to the collecting delivery line 51 . The upper end of the Sammelför derleitung 51 is connected to the river 5 via the discharge channel 53 . The diameter of the header line 51 is reduced at its lower portion where the lower stage pumps are provided so that it can receive the water to be drained from the pumps at the respective stages. The group of pumps 7 is arranged in an underground pump house 61 , which overall has the shape of an upside-down truncated cone. The reason for this form is that less space is required for the installation of the pumps PL with a large pressure head and low delivery capacity in the lower stage than for the installation of the pumps with a low pressure head and large delivery capacity in the upper stage. The underground pump house 61 may have an upper portion having a cylindrical shape and a lower portion having the shape of an upside-down truncated cone, as shown in FIG. 22. A maintenance area M is provided in the underground pump house 61 for servicing the pumps PH and PL and the motors 67 and 68 . As can be seen from Fig. 21, the upper Endab section of the collecting line 51 can be open above the ground surface, so that a fountain or waterfall 69 is present at this upper end portion, the ground surface above the underground pump house 61 a park or the like.

In this embodiment, the difference between the level at which the pumps PH of the upper stage are arranged and between the water level Ho of the river 5 is small since these pumps PH are arranged at the higher level. The required pressure level is therefore reduced, which means a performance saving. If pumps PH of the upper stage have a low pressure head and a large delivery capacity, the operating performance is greatly reduced since the pumping efficiency of the pump with a low pressure head and large delivery capacity is high over a wide range.

If the water level of the pump shaft 6 is low in the water discharge system, the quantity of electricity to be discharged does not have to be large. If the water level of the pump shaft 6 rises, the volume flow to be discharged is increased. Therefore, as shown in Fig. 21, the center water level MWL1 and MWL2, e.g. Ho - 45 m, Ho - 30 m, can be used to control the number of pumps to be operated between the lower water level LWL, e.g. Ho - 60 m , and the highest water level HWL, for example Ho - 15 m. In this case, if the water level rises, the pumps will start up one by one from the lower level to the higher level. This effectively saves electricity in water drainage operations.

Since the plurality of pumps is arranged on at least two stages, the area or space for building the underground pump house 61 can be kept small. This means that the work required for the excavation and thus the construction costs can be reduced. Since the pumps are arranged on a circle, the outer shape of the underground pump house 61 can also be circular, which also contributes to reducing the construction costs.

If the water level in the pump shaft 6 is low, it is not necessary to drain the water quickly. For this reason, the pumps in the lower stage require only a low delivery rate, but a high pressure head. As a result, the area of the associated stage can be smaller, the lower each stage of the underground pump house is. If at least the lower section of the subterranean pump house is in the shape of an upside-down truncated cone, this greatly reduces excavation at great depth and construction costs.

For the pump station arranged in the vertical direction according to 3), reference is made to FIG. 23, which for the pump arrangement of FIG. 12 shows such a pump station in a multi-stage configuration with a vertical drive shaft. A drive motor 71 , the output shaft 87 of which extends vertically, serves as the drive source for the pump impellers (not shown). A pump 72 with a large delivery rate and a low pressure head and a pump 73 with a small delivery rate and a large pressure head are arranged vertically at a distance from one another. Couplings 74 are used for the optional transmission of a torque. The main shaft 87 of the drive motor 71 is connected by the coupling 74 with main shafts 88 of the two pumps 72 and 73 , which are arranged vertically at a distance. The drive motor 71 is provided between the two vertically spaced pumps 72 and 73 for driving the two pumps, which is not shown in detail.

The underground channel 1 is connected to the pump shaft 6 . A delivery line 83 serves as the discharge channel. The multi-stage pump with vertical shaft drive has two or more pumps, in FIG. 23 two pumps which are arranged in the vertical direction at a distance between the pump shaft 6 and the delivery line 83 . A suction line 77-1 of the upper pump 72 is connected to the upper section of the pump shaft 6 via a slide 78-1 . Via a slide 78-2 , a suction device 77-2 of the lower pump 73 is connected to a lower section of the pump shaft 6 . The delivery sides of the pumps 72 and 73 are connected via respective slide 76- 1 and 76-2 to the delivery line 83rd

Water that has flowed from the underground channel 1 into the pump shaft 6 and stored therein flows into the suction lines 77 ( 77-1 and 77-2 ) when the slides 78 ( 78-1 and 78-2 ) are in the open state. The water is then discharged from the pumps to the delivery line 83 . The cross section of an upper portion of the delivery pipe 83 , which extends upward from the portion to which the discharged water is supplied from the pump 72 with a large delivery rate and a low pressure head, is enlarged. The slides 76 ( 76-1 and 76-2 ) on the delivery side are closed when the pumps are stopped or not operating, thereby preventing backflow of pumped water. Arrows 84 and 85 indicate the direction of flow of the water. The reference numerals 81 and 82 denote the water level.

With this construction, the horizontal space is or horizontal surface of the underground water laxative Pumping station smaller than the one conventional pumping station needed.

The main shaft 87 of the drive motor 71 is connected to the main shafts 88 of the pumps 72 and 73 via the couplings 74 , which are able to selectively transmit the torque, so that only the pump impellers required in each case are set in rotation, thereby wasting energy is prevented.

The upper pump 72 has a large delivery rate and a low pressure head, while the lower pump 73 has a small delivery rate and a large pressure head. So if the water level in the pump shaft 6 is at the low level 81 , the pump 73 can operate at a high pressure level. When the water level in the pump shaft 6 is at the high level 82 , the pump 72 can be started up with a low delivery head. The two pumps can also run at the same time.

The drive motor 71 is designed so that it can drive both pumps, which simplifies the overall construction.

Since the delivery line 83 is enlarged in the flow cross section at its upstream portion, the upper portion, the operation can be performed efficiently. The single or common delivery line 83 is used for the plurality of pumps, which makes the construction of the pump arrangement extremely simple.

If, in the embodiment shown, the pump 72 with a large delivery rate and low pressure head does not work, the slides 76-1 and 78-1 , which are respectively provided on opposite sides of the pump 72 , can be closed. Then the water can be removed from this pump so that the pump can be used as a flywheel. This means an energy saving and prevents water hammer.

The pump arrangement of FIG. 12 can have a pump station with a multi-stage pump with vertical shaft drive, as shown in FIG. 24, components corresponding to FIG. 23 having the same reference numerals. The impeller shafts of three vertically spaced pumps 90 are arranged horizontally, the three pumps 90 being constructed identically.

As shown in Fig. 24, a drive motor 71 A has a main shaft 87 A and serves as a drive source for the pumps or pump impellers. Two or more, three in FIG. 24, axial pumps 90 are arranged vertically at a distance from one another. The axial pumps 90 are connected to each other in the vertical direction by connecting shafts 87 b. The main shaft 87 A of the drive motor 71 is connected to the connecting shafts 87 B of the axial pumps 90 through couplings 91 . The axial pump 90 has an axial impeller 89 and guide vanes 92 and 93 . The impeller 89 has a horizontally extending shaft 88 A. The torque is transmitted from the connecting shaft 87 B to the shaft 88 A of the impeller 89 via a bevel gear 94 of a vertical gear. The axial pump 90 has a housing with holes 95 through which the connecting shaft 87 B extends.

The shaft 88 A of the respective impeller 89 is connected via the bevel gear 94 to a clutch 74 for the optional transmission of the torque.

Between the pump shaft 6 , which is connected to the underground channel 1 , and the delivery line 83 , a pump chamber is provided, in which the multi-stage axial pump with vertical shaft drive is arranged, which has two or more axial pumps 90 , three in FIG. 24. On the upstream side, each axial pump 90 is connected to the pump shaft 6 via a slide 78 , downstream of the conveyor line 83 via a slide 76 . In this embodiment, an economical construction of the pumping station and an efficient pumping operation are possible, as in the previous embodiment of FIG. 23. In addition, since the shaft 88 A of the impeller 89 of each pump is arranged horizontally, a mixed flow impeller can be used as the pump impeller instead of the axial impeller.

In this embodiment, the height of a discharge opening or an outlet of the delivery line 23 is constant and the water in the pump shaft 6 is used for displacement. Therefore, regardless of the height of the water level, the pressure levels that are required for the vertically spaced axial pumps 90 are the same, so that the pumps can be constructed identically. For this reason, the pump can form a package, and it is easy to increase the number of pumps. This leads to a reduction in product costs.

The pump to be installed in the pumping station has a large delivery capacity and therefore large dimensions. If the pump generates strong vibrations, the pump housing and the pipe connections are subject to fatigue 07885 00070 552 001000280000000200012000285910777400040 0002004403154 00004 07766. The vibrations create noise, which affects the working environment. For this reason, pumps with reduced pulsation are used to reduce vibrations, as is the case with the centrifugal diffuser pump with single suction according to FIGS. 25 to 27.

A diffuser 103 is arranged around the centrifugal or radial impeller 101 and has a spiral or screw-shaped housing 110 on the outside. The housing 110 has a delivery opening 111 formed in one piece therewith. With the housing 110 , a suction housing 116 is connected, which has a suction opening 115 . The screw-shaped housing 110 and the suction housing 116 together form the water flow section of the diffuser pump.

A partition 105 is provided between opposite side walls 104 A and 104 B of diffuser 103 . A flow channel in the diffuser 103 is divided by the partition 105 into two flow channels 106 A and 106 B, which are independent of one another in the axial direction. In the two channels 106 A and 106 B, a ring of guide blades 107 A and guide blades 107 B are provided and offset from each other in the direction of rotation. The two groups of vanes are mutually offset so that an inlet end of the diffuser blades 106 A and 106 B is located in one of the two channels at a central portion of an inlet end of the diffuser vanes in the other channel. In Fig. 25, the inlet end 107 B 'of the guide vanes 107 B is offset by an angle Φ ° with respect to the A 107 A' of the guide vanes 107 A in the direction of rotation of the impeller. The current enters the diffuser pump through the suction opening 115 and is increased in speed by the rotation of the impeller 1 and conveyed to the diffuser 103 . The velocity of the stream is reduced in the diffuser 103 and static pressure is recovered. The current continues through the screw-shaped housing 110 and is discharged from the pump opening 111 .

The flow at the outlet portion of the impeller 101 is influenced by the thickness of the guide vanes and the development of a boundary layer along the blade surface in the impeller 101 , so that a non-uniform velocity distribution is generated, one division of which corresponds to the intervals between the blades of the impeller 101 . This non-uniform flow passes through the inlets of the diffuser vanes 107 A and 107 B, creating a pressure pulsation that has a basic period that corresponds to the time required for the rotation for this division. The pressure pulsation thus generated is transferred to the screw outlet, while a source of pressure pulsation which is assumed to be transferred to the delivery line. Part of this pressure pulsation wave is transmitted to the intake line via the impeller.

In this embodiment, however, the diffuser channel is divided by the partition 105 into the two channels 106 A and 106 B, which are independent of one another, while the inlet ends 107 A 'and 107 B' of the diffuser blades in these channels are offset from one another in the direction of rotation of the impeller. Therefore, the fluid flows through the channel of the impeller into the two diffuser channels 106 A and 106 B such that the fluids that flow into the two channels 106 A and 106 B, respectively, are shifted from each other by a phase angle Φ ° of the angle of rotation corresponding to this shift , after which the fluid is removed from the Diffusorkanä len 106 a and 106 B. As a result, the pressure pulsations generated at the inlet sections of the diffuser channels 106 A and 106 B cancel each other at the outlet sections due to this phase shift, so that the pressure pulsations at the outlet sections of the diffuser channels are reduced.

If the inlet ends 107 A 'and 107 B' of the blades in the diffuser channels 106 A and 106 B are displaced with respect to each other by an angle which corresponds essentially to half a pitch of the impeller blades, the 106 A and 106 B are generated alternately in the diffuser channels pressure pulsations out of phase with each other by half a wavelength. The pressure pulsations in the two channels therefore cancel each other out, so that they are greatly reduced. The following relationship applies to the above-mentioned angle Φ °:

Φ ° = 1/2 × 360 ° / room
or
360 ° / Zd - Φ ° = 1/2 × 360 ° / Zi,

where Zi the number of blades of the impeller and Zd the Number of blades of the diffuser are.

In this case, the pulsations generated alternately by the two channels 106 A and 106 B are out of phase with respect to one another by half a wavelength, so that the pressure pulses moving forward through the two channels interfere, which greatly reduces them.

Since the inlet ends 107 A 'and 107 B' of the blades in the two channels 106 A and 106 B are shifted from one another, the distance between the inlet end 107 A 'and the pump delivery opening is different from the distance between the inlet end 107 B' and the pump delivery opening . Overall, however, this difference in distance is extremely small compared to the wavelength of Druckpul sation, so that the influence of this difference in distance on the phase shift mentioned can be neglected. It is therefore only necessary to shift by an angle Φ ° in order to satisfy the above equation. As mentioned, in this embodiment, the pulsation is intentionally reduced by giving the diffuser portion a uniform shape. The partition 105 has a disk shape. The blades of the diffuser usually have a two-dimensional design. In the prior art, in which a channel in an impeller is divided by a partition and blades are arranged on opposite sides of the partition so as to reduce pressure pulsation, the partition is shaped to have a curved surface along a streamline for the Case in which the impeller is a single suction centrifugal impeller, and moreover the blades of the impeller are usually three-dimensional in shape. Therefore, the pump can be manufactured more easily in this embodiment than in the prior art.

There is no partition at the inlet portion of the impeller provided, therefore the cavitation effect is not adversely affected.

There is no partition that extends along one Streamline extends in the impeller. Therefore if the Pump works with a low flow rate, the Erzeu supply of a centrifugal flow and a backflow in Impeller is not suppressed, so that deterioration of properties, such as instability of pump pressure height curve does not occur.

Claims (10)

1. Water drainage system arranged at great depth

• - with an underground water channel with a large capacity, which is arranged at a great depth and is slightly inclined,
• - with vertical shafts for guiding the draining water down into the underground channel from flood protection channels provided in the floor surface or near the floor surface,
• - With a pump shaft, which is provided at the downstream end of the underground channel and
• - with a pump station with a pump through which the water flowing into the pump shaft is pumped to rivers or to the sea,

characterized,

• - That an impeller of the pump in the pumping station overall at an average water level of the below earthly channel is arranged and
• - That the pump has such characteristics that it does Water from the full channel, d. H. when closed Water level, with a nominal flow rate, but also out of the canal with an open water level Pump minimum flow.

2. Plant according to claim 1, characterized in that the pump has a maximum efficiency in one menu genstrom reached between the operation with closed, d. H. full channel and with open Channel lies.   3. Plant according to claim 1 or 2, characterized net that the pump has fixed blades. 4. Plant according to claim 1 or 2, characterized net that the pump is a variable pitch pump is. 5. Plant according to claim 1 or 2, characterized net that the pump is designed in two stages and a first impeller with a total head, at which the water from a full channel, d. H. at closed duct flow, pumped with the nominal flow can be, and a second impeller with a Ge has a total pressure at which the water comes from one Channel with an open channel flow with a minimal Volume flow can be pumped. 6. Plant according to one of the preceding claims, characterized in that the pump is underground is arranged at a level that is at least higher than the upper end of the underground channel and that a large volume pump container between the pump shaft and the pump is provided, wherein the bottom of the pump container overall on the same Chen level as the pump is arranged. 7. Procedure for operating the system according to one of the preceding claims, in which in abundance protection channels in the floor surface or in the Draining water near the surface of the floor vertical shafts down into an underground one Flow water channel with large capacity that is at a great depth det and that is slightly inclined, and that that flows away  Eating water flowing into a pump shaft on the river far end of the underground channel flows in Rivers or into the sea through one in a pump station pump is pumped, thereby characterized that a mixed operation with closed channel current and open channel current in which the pump with a mass flow is allowed to work which is larger than the amounts stream of the flowing water is, which in the Pump station in the state with closed sewer flow flows in which the underground channel is complete dig is filled with water, and at which the pump is allowed to work with a mass flow that is smaller than the flow of water flowing in the pumping station in the state with open sewer flow flows in which the water level in the underground channel is lowered. 8. The method according to claim 7, characterized in that

• - that a precipitation amount is calculated on the basis of precipitation information,
• - That the volume flow in the vertical channels is calculated accordingly to the amount of precipitation and an outflow factor which is determined by an interval between a precipitation pattern and a subsequent precipitation pattern, that the volume flow into the pumping station is calculated according to the volume flow in the vertical shafts and
• - That the number of pumps that are to be put into operation and their output is determined in accordance with the volume flow into the pumping station in order to discharge water from the pumping station.

9. The method according to claim 7 or 8, characterized records that when a construction site for the Pumpsta tion is difficult to provide, the system so ge is chosen that the pump is on a total average water level in the underground channel located, and that when the site is easily ready is to be delivered, the system is chosen so that the pump is at a level which is at least higher than an upper end of the underground channel lies, and that between the pump shaft and the pump a large volume pumped storage tank hen.