DE1501362A1 - Channel system for evaporation heat exchanger - Google Patents

Description

Channel system for evaporation heat exchangers

The invention relates to evaporative heat exchangers, and more particularly to an improved apparatus for distributing Water on a heat exchange surface.

Evaporative heat exchangers can generally be divided into two groups:

(1) Open design - Here the fluid to be cooled is directly exposed to the air. An example of this type is a water cooling tower.

(2) Closed design - Here the fluid to be cooled and / or condensed is limited by a Space, for example through a pipe coil, over the outer surface of which air and water flow. An example this design is an evaporation and 3 condenser. 3k? jhl or for Refrigerant,

In the case of a cooling tower with an open design> vird <a ± n part 9 D 9 ? '.. 5/0 2 1 2

of the circulating water evaporates, whereby the heat of evaporation from the rest of the water is supplied. In the case of a closed design, for example an evaporative condensation cooler for refrigerants, part of the water that constantly flows over the outside of the coil is evaporated, wherein the heat of vaporization is provided by the refrigerant or other fluid that is to be condensed or is to be cooled and is in the coil.

With both types of evaporative heat exchangers, the capacity depends on the distribution of the water over the heat exchanger part addicted. In the construction of every evaporation egg care must be taken to keep the water in

small particles are broken up and as a result the largest possible air-water is obtained.

line of the oldest forms of evaporation W & K.r-ti * äUöλ:.? ϊκ "· £! l ^ fe In ä *: r USA patent 1 1- ~ vj 2 b ν t £:;: i * :: -, :: - - .: gi .. Jiig'i. Hach the named patent specification wi: C i; ai .. ^:.; ι & η supplied, the notched side walls ha-Ik ^ ₁ J vciC. iäuifc the water in the form of several streams from the ami .; iöSi'3J Hbsi '* Aue of the patent specification mentioned, it emerges that part of this water is drained by the natural circulation of the ambient air From the patent it emerges that the channels are so angfi ^ Kcntfc B ± xi5. that the air does not flow in countercurrent to the water in the gutters, but rather touches the water in the cross-section. The water leaving the channels is, however, only slightly divided so that the air-water interface is very small

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existing air movements and the area requirement was large in relation to the capacity.

To enlarge the Zwisohenfläohe air-water went the use of gutters was then abandoned and, mostly working in the Qegenetrom, "evaporative heat exchangers" were used Usually with spray nozzles to keep the water in Droplet shape was distributed over the heat exchanger part. That ^ repressed water falls under the effect of gravity the heat exchanger part and flows in countercurrent to the air flowing upwards, which is conveyed by a fan.

I am an evaporation heat exchanger with spray nozzles for the However, water distribution has several disadvantages. The nozzles are relocated by foreign bodies that star in the Umwälzey si <d, so that "dry spots" on the heat exchanger surface occur, reducing the capacity. The Sprtiheyetem must be checked at short intervals so that it ■ tete is clean. Furthermore, the manufacture of a distributor with fuel nozzles very expensive. In addition, a pressure loss occurs in a spray system in the spinnerets, so that a higher pumping capacity is required than with a system provided with grooves and working under the effect of gravity Distributing water. As a result, a stronger and more expensive circulation pump must be used.

The invention beeweokt to avoid the disadvantages of the known devices and to create a system for the countercurrent flow of water and air, which can be built and maintained economically, but by a very large area between air and water, a very fast heat exchange and an Ib ratio to the space requirement is very large

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Cooling capacity is excellent.

The invention provides a runned-out heat dissipation system, in which the water overflowing from the gutters is guided in countercurrent to air that a Spray mist is formed from finely divided droplets with a large air-water interface.

The invention is also for maintenance purposes an even distribution of water over the entire length of the gutters and a subdivision of the water overflowing from these gutters Water in numerous streams, so that those guided on the interaction between the water currents and the countercurrent Air-recirculating generation of the spray still is supported.

Further purposes and advantages of the invention will become apparent from the following detailed description of several exemplary embodiments of heat exchangers according to the invention with reference to the drawings. In this shows:

Fig. 1 schematically in vertical section an evaporative condensation cooler or cooler for fluids with the gutters for water distribution and the countercurrent air system according to the invention.

Fig. 2 also shows schematically in vertical section an evaporation cooler in an open design (cooling tower) with the channels for the water distribution and the countercurrent air system according to the invention.

Fig. 3 shows a single one according to the invention on a larger scale formed gutter partly in section and partly in view with the system for supplying water to the gutter.

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Fig. 6 shows diagrammatically a part of a modified embodiment of a channel for the production of several, spaced streams.

FIG. 7 shows a cross section through a channel according to FIG. 6.

Fig. 8 is a perspective view of part of a notched trough which is corrugated tangent to its bottom Has baffle, which in cross section has the shape of a downwardly open sickle and serves a large number of currents into the countercurrent air. Fig. 9 shows in a similar representation to 8 shows a baffle surface with a sickle-shaped cross section with notches instead of waves.

Fig. 10 shows in a view similar to Fig 8 ₀ a crescent-shaped in cross section, baffle, which is corrugated only at their edges.

FIG. 11 shows a diagrammatic view of part of a channel according to FIG. 6 with a partial organ of the type shown in FIG. 8

FIG. 12 shows that shown in FIG. 11 in cross section Embodiment of the invention.

According to Fig. 1, a chamber 10 is at its upper end with a group of channels 11 and at its lower end with a sump 12 is provided. In the side walls of the gutters are V-shaped notches 13 (see Fig. 3) are provided. The gutters in

_ω of one side wall are opposite to the grooves in the other

■ o-side wall offset. From the notches 13 of the grooves 11 overflow

^ fende water flows in droplet form through the heat exchanger tubes ^ 14 and is caught in the tray 12 and from there mil; one Pump 15 reclaimed via a line 16 to the channels 1i.

Make-up water passes through a line 17 under control a float valve 18 controlled by a float 19 which is arranged in the sump 12.

A centrifugal fan 20 promotes air through the Guide 21. This air flows up through the chamber 10 in the Countercurrent to the water emerging from the channels 11. After passing through the heat exchanger 14, the air flows between the gutters 11 and through mist removers 22 into the atmosphere. The circulated through the heat exchanger tubes 14 Fluid that is to be cooled is caused by the evaporation of the overflowed through the notches 13 of the channels and the outer surface of the tubes 14 wetting water removed heat.

The foregoing was briefly an evaporative heat exchanger described, except for the channel arrangement according to the invention and the water distribution system according to the submitted at the same time Registration of Thomas F. Pacius in its structure and its working method is common.

If the heat exchanger 14 is used, for example, to condense a refrigerant, only so much water needs to be supplied that the outer surface of the tubes is constantly wetted. In the inventive use of grooves having a round bottom, whose curvature is clear from Fig. 4, the light emerging from these grooves water is distributed so as to ο be spaced at great distances, and only about 25-30% of the cross-section of the Chamber 10 in

oo occupy the plane AA, but still ensure that the ^ tubes 14 are kept constantly wet. The this-purpose · J ₀ construction can to the figures 3 and 4 erläuk> be tert best.

Near the top of the chamber 10 is a

Chamber 23 is arranged, which is fed from the line 16 centrally. This chamber 23 is limited in part by a wall 24, which separates the chamber 23 from a container 25 and also delimits this. The container 25 is also supported by a bottom wall 26, which it has in common with the chamber 23, and by a wall 27, which can be seen from FIG. The wall 24 is formed with a series of spaced round holes 28 which allow the liquid to pass between the chamber 23 and the container 25. the Wall 27 is formed with a group of outlet openings 29 which are each assigned to one of the channels 11 and of which in Figure 4 four are visible. The openings 29 correspond generally the cross-section of the channel, but end below the steady water level in the channels 11. That from the line 16 escaping water enters near the center of the chamber 23, then flows through the holes 28 in the intermediate wall 24 and maintains a uniform temperature in the container 25 Upright water level. One of the holes 28 is assigned to every three fed channels. The height of the chamber 23 corresponds to Diameter of the tube 16 so that the amount flowing into the chamber from the tube is approximately the same as the amount flowing out the web of a T-shaped piece flows into its flange. The container 25 is emptied through the openings 29 in each of the channels. The water runs in from the V-shaped notches in the gutters co the heat exchange area about. Seek the overflowing streams

* - to adhere to the side walls that are in. with the dispensing notches

^ are formed, and leave the gully considerably beyond _ * of the vertical center line on the opposite side of the gutter from the dispensing notch. If there is no countercurrent

If there is air, these currents fall down, as is the case in the Figures 1,2,3 and 4 is shown. The stream 30 therefore emerges from a notch in the right-hand side of the channel 11 in FIG. 4 and the stream 31 emerges from a notch in the left-hand side of the channel 11 in FIG. Those on opposite sides of the Notches 13 arranged in grooves 11 are axially offset from one another as shown in FIG. 3, so that the currents 30 and 31 are also axially offset from one another and do not touch one another. If now the Air flow is generated, the shape of the flows undergoes a significant change, as can be seen from FIG. 5. The on Stream running down the side wall of a gutter becomes somewhat shallower as it approaches the bottom of the gutter. In the presence of an air flow, the flow becomes flatter and rounded then again when it flows over the bottom center line of the channel and from the countercurrent air from the channel is torn away. The moment the stream is separated from the gutter, it literally explodes with the formation of Droplet. Attempts have been made to illustrate these phenomena in FIG.

If the streams 30 and 31 are not displaced by the air, they form an angle o \ with the vertical center line of the channel. In the context of the invention it was recognized that this angle Λ with the curvature of the bottom of the channel in

is in a relationship. The channels shown in Fig. 4 have co

° almost parallel side walls, which are separated by an arch with equal

4>. permanent radius are connected to each other. It depends on that

** ·> the desired result, whether such a bend is suitable for the ^ the radius of curvature of the bottom of the channels is decisive. If the gutters at the bottom are in the ^{shape of} a sharp V, the angle is -A

very small and the distances between the channels must be small so that a good distribution of the water is achieved. With gutters in Pig. 4, a good distribution of the water is achieved with minimal relocation of the air flow space. According to FIG. 1, the channels shown in FIG. 4 are arranged at fairly large distances from one another, so that they only take up about 25-30 % of the cross-sectional area of the chamber 10 in the plane AA. It has been shown that this arrangement leads to good wetting for the tubes of evaporative condensation coolers.

The channels 11 are carried by support pieces 32 and 33. Each support piece 32 is provided with inner flans 34 and 35, the ones with self-tapping screws on the partition 27 are attached, the channel · with the corresponding opening 29 corresponds (see FIG. 4). The support piece 33 is held in a similar manner by flanges 37, of which in the Drawings only one is shown. Each gutter is in a sealant at both ends in the corresponding hanging support pieces 3-9 embedded.

The water distribution system of the one shown in FIG Cooling tower is very similar to that shown in FIG. As a result of the larger amounts of flow required, the channels 11 but arranged at much smaller distances from one another. In

take the illustrated embodiment of the invention sit co

approximately 45 % of the cross-section of the chamber 10 in the plane AA.

J? In Figures 1 and 2 are the same parts with the same Beauge-

- ^ numbers denoted. In Fig. 2, however, no WMrmetaueoh-

^ tubes provided, but the Wärmetichbereioh is occupied with white plates 39. Ee several of these plates 39 are provided -

see, so that there is a larger water-wetted area and therefore also a large interface · air-water.

In the arrangement according to FIG. 2, the water to be cooled is supplied from the pipeline 40 and in the on the basis of the Figures 1, 3, 4 and 5 are released from the channels 11 in the manner described. Some of this water evaporates, eliminating the rest of the hot water supplied via line 40 until it is reached the sump 12 is cooled. The cooled water is drawn off from the sump 12 via a line 41.

Figures 6 and 7 show parts of a gutter 40 which has straight edges and is used in place of or in conjunction with gutters can be, as they are designated in Figures 1 to 5 with 11. Since the gutter 40 is installed and used similarly are to be like the channels 11, only the differences in the design between the channels are described. A corrugated U-profile 41 is arranged within each channel 40, whose side walls 42 and 43 with their convex waves under pressure tangentially on the opposite inner surfaces of the Side walls of the channel 40 and are held in this position by the one-piece bow 44 of the U-profile. As the waves of the channel 41 run diagonally, the waves of the side wall 42 of the U-profile 41 are opposite to those of the side wall 43 offset so that the concave waves with the side wall of the

Channel forming several vertical channels · 45, which extend from the co

° upper edges of the gutter 40 to the free lower edge of the enter »

^ speaking Seitonwand 42 or 43 extend. In the event of an

^ run out of the rivulet, hence numerous streams from it

* ·> From, similar to the currents emerging from a channel · 11.

In a ventilation system for evaporation

Heat exchangers, it is expedient to deliver the water in the smallest possible streams so that the largest possible air-water intermediate surface is obtained. In the channels 11, the notches of each side wall are offset from the notches of the other side wall so that the water emerging from each notch leaves the channel in its own stream (Fig. 1-5). Essentially the same effect is achieved with the modified embodiment of the invention shown in FIGS. These measures for the formation of individual streams which overflow from the edge of the channel are expedient for relatively low flow rates, as they are, for example, in evaporative condensation coolers or evaporative coolers for fluids as well as in cooling towers with relatively small flow rates. If larger flow rates of the water are required, the water tends to form contiguous surfaces as it leaves the notches of gutters according to FIGS. 1 to 7. If this effect is not suppressed, it sets the atomization of the water and thereby the efficiency of the tower down because not the largest possible space between air and water is achieved. Fig. 8 now shows an improved channel which has proven itself very well with very large amounts of water flowing Has.

The channels according to FIG. 8 and the channels according to FIGS. 9, 10, 11 and 12 are for use in one

ο fung heat exchangers and should be in this in the co

Hand of the type described in Figures 1 and 5 can be assembled. There-

only parts of a channel are shown in Figures 8 to 12,

explaining various modifications that have proven useful when the water flows in large quantities.

Fig. 8 shows "ine Rinnt 46, which in their free RMn-

i the notches 47, which in their training and function the notches 13 described above is similar, in the bottom of However, channel 46 is attached tangentially to a corrugated baffle surface 48 which has an egg-shaped cross-section. This baffle has waves in a number equal to the number of notches considerably exceeds. The water running down the sides of the channel 46 is broken up by the waves and in a large number of very small goiter released into the air guided in the doge stream. It has been shown that with such an arrangement large amounts of water flow when the water flows Interfaces between air and water are formed. In the exemplary embodiment shown, the notches 47 are in the side wall the channel 46 offset from the waves of the impact surface and arranged in a larger pitch than the waves mentioned. However, the baffle surface 48 is so effective that numerous flat notches which are not offset with respect to the shafts, lead to a perfectly flawless result.

9 shows a channel 49 which is similar to channel 46 in every way. In FIG. 9, however, the baffle surface 50, which is sickle-shaped in cross section, is not corrugated, but is provided with V-shaped notches 51 along its opposite edges. These notches 51 are present in greater numbers and

shallower than the notches 52 through which the water from the gutter co

Overflows. In Fig. 9, no attempt has been made to determine the flow J £ to represent water flowing off from the baffle 50. This

■ ^ Water forms streams that fall down from the notches 51.

* J The channel 53 shown in Fig. 10 also corresponds entirely to

lig of the channel 46. In this case, the cross-section is sickle

shaped bouncing surface 54 is only corrugated at their opposing edges 55. At these edges, the water runs off in the manner shown in Fig. Θ. The pitch of the notches 51 in Fig. S and the shafts 55 in Fig. 10 is much smaller than that (division of the main overflow notches to the groove, so that numerous small streams are introduced into the air flow. For a channel, the composite having a Cross-section sickle-shaped baffle of the type shown in Figures 8, 9 and 10 is used, but the number and depth of the notches in the side walls of the channel must be chosen so that a uniform overflow is obtained over the entire length of the channel, because the The distances between the streams of water, which are introduced into the counter-current air, depend on the number and size of the waves or teeth of the crescent-shaped impact surface.

The baffles 48, 50 or 54 can be at the bottom of the Corresponding grooves can be fixed by welding or with Bleoh connection screws.

Figures 11 and 12 show a gutter essentially of the type shown in Figures 6 and 7, however with a corrugated impact surface of a sickle-shaped cross-section tangential to the bottom of the channel.

In Fig. 11 a channel 56 is provided in the interior with a corrugated component 57, which leads to the formation of the flows, co

which overflow over the straight edge of the channel 56. The component

j>. 57 resembles that in Figures cn

^ 6 and 7 shown U-profile 41. The corrugated Prallfläoht 58 ο

^ is similar in its training and function to the impact surface 48, but the waves need not be offset.

Xn in Figures 6,7t8 and 11 are the currents that result from flow down the back or from the baffles, which are sickle-shaped in cross-section, in the shape they take on in the absence of an air flow. These gutters are j β do oh with acted upon by air guided in the counter flow, so that the water flows essentially in the one shown in FIG Way be divided by the countercurrent air.

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Claims (1)

- $ 1 patent claims 1 # Runs to supply water to an evaporation heat exchanger, characterized in that it has a one-piece construction with parallel 8 * ltenwalls, which are arranged at a distance from one another and connected to one another by a part which extends aioh over an arc of 180 °, the side walls having swei free bands and with deep notches formed and whose mouths match the free binders of the side walls and their depth is smaller is measured as the rolling depth of the side walls, from the corresponding free bands at the beginning of the part that extends over an arc of 160 ° 2. Trough sum supply of water su a vaporization heat exchanger, characterized in that it has a one-piece bleoh construction with parallel rare walls, which are arranged at a distance from one another and connected to one another duroh a regularly curved part that extends over Extends 180 °, the side wall swel having free bands and are formed with regularly spaced, deep, V-shaped notches, the mouths of which with the free The edges of the side walls match and their depth is smaller is as the full depth of the rare walls, measured from the corresponding free edges to the beginning of the curved part, and wherein the notches are axially offset from one another. 3. Channel for supplying water to a Verdampfunga heat exchanger, characterized in that it has a one-piece sheet metal construction with parallel side walls, 909845/0212 BADORlQfNAL which are arranged at a distance from one another and connected to one another by a regularly curved part that extends over 180 °, the side walls have two free edges and with regularly spaced, deep, V-shaped Notches are formed, the mouths of which match the free edges of the side walls and the depth of which is smaller is measured as the full depth of the sidewalls, from the corresponding free edges to the start of the curved portion, and wherein the notches of one side wall are axially offset from those of the other side wall. 4. Trough for supplying water to an evaporative heat exchanger, characterized in that it has a one-piece sheet metal construction with parallel side walls, which are arranged at a distance from one another and connected to one another by a regularly curved part that extends over 180 °, the side walls have two free edges and with regularly spaced, deep, V-shaped Notches are formed, the mouths of which coincide with the free edges of the side walls, and the depth the side wall from the beginning of the curved part to the bottom of the notches corresponds approximately to the distance between the side walls. 5. Device for supplying water to an evaporation heat exchanger, characterized by a gutter, further means for supplying water to the gutter, a corrugated one Wall and means for stopping the corrugated wall against the inner surface of a side wall of the channel such that the corrugated Wall with the inner surface delimited spaced channels through which water overflows from the gutter 909845/0212 in a number of spaced streams is fed to the edge of the gutter. 6. Apparatus for supplying water to an evaporative heat exchanger, characterized by a gutter, further means for supplying water to the gutter, a corrugated wall and means for stopping the -b «id ·» - corrugated walls, on the inner surface each a side wall of the trough such that the corrugated wall with the inner surface defines spaced channels through which water overflowing from the trough is supplied to the edge of the trough in a number of spaced streams. 7. Device for supplying water to an evaporation heat exchanger, characterized by a channel, further Means for supplying water to the gutter, means for causing water to come from the opposite edges the gutter overflows in a number of spaced streams, and means associated with the gutter, which the water of these streams into a greater number of streams parts that enter the heat exchange area. 8. Device for supplying water to an evaporation heat exchanger, characterized by a gutter, further means for supplying water to the gutter, the free Edges of the gutter form deep notches which cause water from the opposite edges of the gutter in a Number of streams arranged at a distance from one another overflows, and means are assigned to the channel which the Divide water of these streams into a greater number of streams that enter the heat exchange area. 909845/0212 9. Device for supplying water to an evaporation heat exchanger, characterized by a gutter, further means for supplying water to the gutter, a corrugated one Wall and means for stopping the corrugated wall against the inner surface of a side wall of the channel such that the corrugated Wall with the inner surface delimited spaced channels through which water overflows from the gutter is supplied to the edge of the gutter in a number of spaced streams and in the form of these streams flows from the edge of the channel, and means are assigned to the channel, which the water of these streams in a larger number share of flows entering the heat exchange area, 10. Device for supplying water to an evaporation heat exchanger, characterized by a gutter, further means for supplying water to the gutter, means which cause water to flow from the opposite edges of the gutter in a number of spaced apart Streams overflows and a generally sickle-shaped baffle in cross-section that touches the bottom of the gutter are arranged in such a position that it catches the water overflowing from the gutter, the edges of the baffle form a pattern of edge parts which are offset from one another in at least one plane. 11. Device for supplying water to a heat of vaporization exchanger, characterized by a channel, further means for supplying water to the channel, means that cause water to flow from the opposite edges of the gutter in a number of spaced apart 909845/0212 ordered strumen overflows and one in cross-section in general sickle-shaped baffle that touches the bottom of the gutter are arranged in such a position that it catches the water overflowing from the channel and the edges of the baffle have waves that have a smaller pitch than the streams overflowing from the gutter. 12. Device for supplying water to einom evaporative heat exchanger, characterized by a trough, further means for supplying water to the trough, means which cause water to overflow from the opposite edges of the trough in a number of spaced apart strums, and a generally crescent-shaped baffle in cross-section contacting the bottom of the trough are arranged in such a position that it catches the water overflowing from the gutter, and the edges of the baffle are provided with notches in a number which is greater than the number of streams that overflow the channel edge. 13. Evaporative heat exchanger with one chamber in which a heat exchange area is provided, characterized duroh several generally U-shaped channels, which are in horizontal Distances from one another above the said area are distributed over the entire cross-section of the chamber, means that cause water to flow in a number of spaced streams across the opposing ones Edges of each gutter overflows, and means for creating one Air flow flowing upwards and between the said range up the gutters to the separate streams atomize. 909845/0212 bad original 14 «Device for supplying water to an evaporative heat exchanger, characterized by a gutter, further means for supplying water to the gutter, means which cause water to overflow from the opposite edges of the trough in a number of spaced streams, means associated with the trough which divide the water of these streams into a greater number of streams entering the heat exchange area and means for Generation of a stream of air which is guided upwards through said areas against the streams in order to atomize their water. 15. Evaporative heat exchanger with one chamber in which is provided a Wärmetausohbereioh, characterized by several generally U-shaped gutters in horizontal Distances from one another above the said area are distributed over the entire cross-section of the chamber, each channel has parallel side walls with V-shaped notches, the side walls between the bottom of the notches and the beginning of the Curvature at the bottom of the gutter have mutually parallel parts, means for introducing water into the gutters so that the water exits the notches and in the form of camouflaged streams flowing downwardly and means for creating a stream of air which is directed upward through said area and between the troughs to atomize the separated streams. 16. Evaporation heat exchanger with a chamber containing a condensation cooler, characterized by several, generally U-shaped gutters that are spaced horizontally from each other -above the condensation cooler over the whole 909845/0212 BATH ORIGINAL Cross-section of the chamber are distributed, each trough in a side wall has V-shaped notches, the troughs occupy about 25-30% of the cross-section of the chamber in the horizontal plane in which the troughs have the greatest width, means for introducing water into the Gutters, so that water emerges from the notches and flows downwards in the form of separate streams, and means for creating a stream of air which is guided through said area and up between the gutters to atomize the separate streams. 909845/0212