CZ26615U1 - Infiltrometer and permeameter kit with controlled volume pump - Google Patents

Description

The solution concerns the innovation of continuous infiltrometer (UV 23245, respectively PV 2011-245) with the aim of extending its use in addition to flood warning systems as well as equipment for field and laboratory measurement of water infiltration into soil and for determination of soil soil hydraulic characteristics hydraulic conductivity.

The device according to the technical solution is based on the design of a continuous infiltrometer (UV 23245) from the same originators, which is newly supplemented with design modifications for filling the borehole with water and its infiltration into the tested soil resp. for pumping water out from the test soil. In addition, the device also allows use for laboratory testing of soil samples.

BACKGROUND OF THE INVENTION

Water flow in a porous environment, such as soil, is determined by the entire complex of abiotic and biotic influences: grain size, pore character and stratification, biological recovery, chemical properties or land use. Water penetrates the soil not only from the surface of the land, but also moves below the surface depending on the gradient of potentials (levels, temperatures, concentrations, etc.) acting on it. Soil infiltration ability and soil permeability for water are the main hydro-physical parameters for describing runoff and water retention capacity in the landscape, and subsequently for designing water management measures within the river basin. The water movement in the soil is formulated using the Darcy-Buckingham-Richards theory of water movement, which, after adjustments and appropriate selection, is used to numerically express the results of the tests performed.

In order to describe a complex, often non-stationary, water flow process in a porous environment, it is advantageous to fix some boundary conditions at a measurable level (such as the hydraulic potential of levels) during testing. This simplifies the subsequent evaluation of the test and reduces the error of the measured parameter.

Both characteristics can be determined in the laboratory on a pre-sampled soil or in the field. Within the laboratory determination we can better influence and fix hydraulic boundary conditions. The disadvantage, however, is the size limits of the sample, which may change the effects acting differently in the field (especially the measurement of infiltration capability). Furthermore, there is a risk of mechanical damage to the sample during collection, transport and installation in the laboratory. For these reasons, field methods provide the most representative results, but require special equipment and precise adherence to working procedures. Manual measurements are time-consuming, and automation typically requires complex and costly equipment. Indirect methods for determining these parameters are not discussed here, as they provide parameter values with a high degree of uncertainty and are therefore only indicative.

Traditional manual methods for direct determination of hydraulic conductivity K [I, ť ¹ ] (expressed by saturated hydraulic conductivity coefficient according to Darcy law) by field methods include the so-called single-probe or two-probe method (similar to pumping tests) when the probe drains groundwater, respectively. the filled probe method (equivalent to the heating / pressure test), if the probe is situated at a horizon above the groundwater level. With these methods, a change in the level in the probe over time after one-time drain or one-off water is recorded (variable-level test). Infiltration meters of various types (vacuum, heating, with constant or variable level) are used to measure infiltration capability.

The disadvantages of the above types of equipment are either their considerable structural demands or special conditions of use (eg PV 2011-584 solution), less suitable or unsuitable for testing moderately permeable non-cohesive materials such as soils, especially if the test conditions vary according to the current level groundwater in the measured profile at the time of testing. Other devices either do not have an automated data logger (see Guelph permeameter

- 1 CZ 26615 Ul

Soilmoisture equipment corp.) Or are complex to operate, or may only be assembled for one type of test (eg Soilmoisture equipment corp Aardvark permeameter, for pumping test). Conversely, very simple devices (float field kits; /) require continuous operator supervision and manual readings. Under the climatic conditions of the Czech Republic it is necessary to choose the test method according to the current water regime of the locality at the time of the survey and to appropriately combine field and laboratory methods. This universal kit is currently not available.

The essence of the technical solution

The above-mentioned drawbacks are eliminated by the device according to the invention, which consists in that the water is either supplied to the application probe or pumped out of the application probe by means of a precise metering pump. The application probe is designed as a ground casing or as a stop ring, for laboratory purposes as a sampling roller with an annular extension. The control unit maintains the selected water level based on a continuous level dip test by pumping water in either direction. The level tip is freely adjustable over the height of the application probe and then mechanically fixed. The solution ensures that the level tip does not undesirably come into contact with the electrically conductive parts of the application probe. Contact of the level tip with the water level in the application probe causes the control unit's low-current electrical circuit to be closed, indicating when the level is reached or when the level tip is below the water level. Protection of the dosing unit device against abrasion by soil particles and impurities in water is solved by a sinter filter, installed according to the measuring mode either on the water pipeline or as a direct part of the ground application probe. The control unit ensures measurement automation and at the same time provides data about the time course of the test for archiving in the datalogger.

The infiltrometer and permeameter set according to the technical solution allows operation in four modes:

- use as in-situ permeameter based on filled probe principle

- use as in-line permeameter based on pumped probe principle

- use as laboratory permeate

- use as infiltrometer in sieve (existing solution according to UV 23245, modified by treatment, minimizing water loss by evaporation)

Advantages of the solution:

- the versatility of using the kit as a permeameter according to local conditions, depending on the current level of steady water level in the test soil relative to the ground probe (a / level is within the active probe length; b / level is below ground probe)

- universality of use as infiltrometer with constant level of discharge or resp. a constant displacement meter

- universality of use for determining the firing time (with controlled sprinkling intensity) - see UV 23245

- measurement automation and electronic archiving of measured data

The infiltrometer and permeameter set according to the invention is characterized in that the water dosing unit supplies or drains (depending on the application) water to / from the application probe depending on the signaling of reaching the set level by means of a level tip. The immersion of the level tip with respect to the water level in the application probe is evaluated by the control unit and stored in the datalogger synchronously with the time information. Water distribution is provided by the distribution piping. To protect the dosing unit (dosing pump) against impurities contained in the water, a water filter located on the water distribution system (depending on the application, always on the suction branch of the pipeline) provides protection. The electrical connection of the surface tip and the ground tip grounding to the control unit provides electrical wiring.

-2 GB 26615 U1

The application probe is adapted for use in the following variants:

- Permeameter: designed as a perforated earth casing, inserted into a pre-drilled hole in the soil or driven into the soil, the perforation ensuring the hydraulic connection of the external environment to the interior of the casing and reducing the penetration rate of earth particles into the probe. The advantage of the solution is its simplicity of construction and the associated low production cost. The disadvantage is lower resistance to flooding of earth particles into the application probe and usually also worse hydraulic connection of the application probe with the tested soil (due to flats of solid material of the casing body, separating individual holes of perforation). When pumping water from the application probe (used as a pumped probe), it is necessary to use a water filter on the suction line to protect the dosing unit.

- Permeameter: designed as a ground casing, applied according to the variant above, perforation is replaced by a granular sinter filter, with a hydraulic conductivity at least an order of magnitude higher than the test soil and with a very low air inlet value. Sinter simultaneously serves as a casing and a filter limiting the flow of earth particles. Advantages include improved hydraulic connection of the application probe to the test soil, structural rigidity allowing greater force to be applied to the application probe, as well as the efficacy of the first stage of water filtration from the soil, ie optimal protection of the application unit from soil particles. The disadvantage is the higher price, due to the need to use special sinter fittings.

- Infiltrometer: design as a stop ring or sampling roller with extension. It allows testing the soil surface in a sown field (in sieve) or in the laboratory after taking an intact sample. In such cases, it is necessary to ensure water spraying on the surface of the test soil, eg by means of a sprinkler at the end of the water distribution, or by installing a coarse sintered sinter plate on the soil surface. that the sampling roller is submerged.

When using the permeameter as a pumped probe, water flows directly from the aquifers test soil environment (the groundwater level must be higher than the level probe tip in the application probe). In this case, the water source is eliminated. In other cases of use, as a permeameter on the principle of a filled probe or as an infiltrometer, a water source is included.

The kit according to the invention is further characterized in that it is suitable for automated field measurement of soil surface infiltration potential or water permeability, respecting current soil conditions and conditions.

After the end of the test, the data are transferred from the datalogger to the PC and further processed for the required purpose.

The infiltrometer and permeameter set with metering pump according to the invention will find application as a mobile device for the realization of hydropedological survey, for the equipment of soil laboratories or according to UV 23245 as an autonomous sensor of meteorological stations with the function of generating warning messages about local floods.

The advantages of the kit according to the invention can be summarized as follows:

- universality of equipment for different purposes and conditions of use,

- compactness of the design and composition with the possibility of connection to other monitoring systems,

- Simplicity of design and operation while fully automating measurements.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, FIG. 1 schematically shows the basic functional diagram of the kit for the main modes of use.

In FIG. 2 shows methods of the technical solution of the application probe also for use as a probe of a permeameter in a borehole or as a stop ring of an infiltrometer or a sampling cylinder

-3GB 26615 UL with laboratory test adapter. In all designs, the height-adjustable level tip 7 is designed in such a way that it is electrically insulated from the components of the application probe I, which in the electrically conductive version is always connected to ground 8 of the level tip 7.

In FIG. 3 is a wiring diagram using the kit as a permeameter as a filled probe. Typically, the dosing unit 2 supplies water from the water source 4 to the application probe 1, which is in the design of a ground casing (Fig. 2) via a water filter 4. The steady water level 10 in the test soil is lower than the maintained set water level 11 in the application probe i.

In FIG. 4 is a wiring diagram when using the kit as a permeameter as a pumped probe. It is typical for this connection that the dosing unit 2 pumped water through the water filter 4 into the application probe 1 from the surrounding test soil. Application probe I is designed as a ground casing (Fig. 2). The steady water level 10 in the test soil is higher than the set water level 11 in the application probe 1. In this embodiment, the water source 6 is missing, but the vessel can serve to capture the effluent and subsequently calibrate the measurement.

In FIG. 5 is a wiring diagram when using the kit as an in-line infiltrometer or a permeator in a laboratory. Typically, the dispensing unit 2 delivers water from the water filter 4 to the application probe 1, which is in the form of a stop ring or a take-up roller with an extension (Fig. 2). The steady water level 10 in the test soil or outside the application probe 1 when used in the laboratory is below the maintained set level 11 of the application probe 1. In the case of using clean water without impurities, the water filter 4 may be omitted.

The following exemplary embodiments of the infiltrometer and permeameter with metering pump set according to the invention only illustrate without limiting it.

Examples

Example 1

A prototype of a continuous infiltrometer (according to UV 23245) in the form of an innovated infiltrometer and permeameter kit with a metering pump according to the invention was manufactured at the end of 2012 according to the proposal of the Research Institute of Soil Amelioration and Protection v.v.i., CZ by ADCIS, s.r.o., CZ. The original electronic part of the control unit was replaced by a microprocessor and internal memory for archiving the set parameters (measurement mode, measurement results, etc.). A new method of use as a permeameter and a laboratory permeate has also been developed. In 2013, field and laboratory testing was carried out, including a proposal for minor structural and softwaer modifications to the program. The solution was adapted for small series production.

The control unit 3 with microprocessor and internal clock 16 generating real time uses both internal memory in the function of data logger 15 and also enables connection of external pulse data logger (here used OM-CP-PULCEIOIA by Omega (www.Omega.com), providing comfort archiving and pre-processing of data). Soffwaer equipment (SW) enables optional programming of the control unit 3, including direct connection to a personal computer for on-line transmission of measured data. It also allows the water supply to be vented by manually turning the pump on and off or calibrating by triggering a 1000 pulse dose.

Application probe 1 was made in several design variants (see Fig. 2). For the version of the casing, variants were made of water pipes (PVC / polyvinyl chloride / i galvanized iron pipes of diameter Gl ”/ one inch-inch) of 900 mm length, ending with bronze atrium fittings of 0.315 to 0.63 mm (threaded fitting) Gl). Above, the level tip 7 is fixed by a PVC G1 plumbing plug, simultaneously filling the function of the water vapor-reducing top cover 14, with drilled holes for the water distribution pipe 5, to transmit the power line 7 of the level tip 7 and to aerate the space above the surface. In this solution, the level tip 7 is made of a welding electrode of a stainless steel wire about 1000 mm long, 2 mm in diameter, ground at the bottom, connected to the power line 9 at the top.

26615 U1 of the tip 7 is provided by a sleeve attaching the electrical wiring 9 to the conductive body of the probe. Both conductors of the power line 7 (connection of the control unit 3 with the surface tip 7 and ground 8) are made of two lines of copper wire cross section 2 x 0.25 mm ² . Alternatively, 50 mm and 500 mm length probes were produced for smaller soil well depths. The soil drill G1 was used to pre-drill a well of adequate depth and the casing of the application probe 1 was tightly inserted.

As a water filter, a bronze sinter filter in a glass container and with screw connection was used for easy cleaning.

The original version (see UV 23245) of stainless steel with internal diameter of 100 mm (area = 78.5 cm ² ), height 50 to 100 mm, with a blade pressed into the soil to a depth of about 30 to 80 mm below ground level 13. The same ring can also be used for taking an intact soil sample and for subsequent processing in the laboratory. The same ring, shortened to a height of about 30 mm, then attached from above with adhesive tape or a rubber ring seal, is used as a level 11 attachment. It is also possible to use other, usually smaller, ring diameters - for example Kopecky rollers. For scrubbing the surface of the soil, a preformed 5 mm diameter copper tube (corresponding to the pipe diameter / water distribution hose 5) is used with a drilled row of apertures of approximately 1 mm spaced around the inner perimeter of the tube so that water is directed to the center of the application probe roller.

Silicone tubing with a diameter of 6 mm, in lengths of approximately 500 to 1000 mm, is used for water distribution 5, depending on the arrangement of the measuring station. This tubing diameter corresponds to the water dispensing unit 2 outlets (IWAKI Electromagnetic Diaphragm Pump model HRP-54H-1P2 - built-in horizontal with pulse control, 12 V supply voltage, digitally controlled stroke range 0 to 720 strokes, min ' ¹ , which represents a maximum flow rate of 38 ml.min ¹ ).

If the dosing capacity of the pump used does not meet the requirements of, for example, very permeable soils or bulky casing or larger infiltration areas, the pumps can be grouped or a more powerful type of dosing pump can be selected.

As part of the test procedure, it is recommended to calibrate the hydraulic performance of the pump under specific conditions at the beginning and at the end of the test, although the IWAKI pump manufacturer guarantees high accuracy and dosing stability for this series.

The electronic part of the kit contains a microprocessor control unit with a two-line display, one multifunctional operating button, a pair of connectors (one for connection to a personal computer or for external power / charging; the other for connection to external data logger and external operation) battery 12V / 2.2 Ah, allowing all day uninterrupted operation, two built-in dosing pumps, operated singly or simultaneously. All installed in PVC wiring box.

Industrial applicability

The invention relates to an infiltrometer and a permeameter for measuring the soil hydrophysical characteristics in situ or for use in a laboratory. Parameters describing the process of water filtration and infiltration can be derived from the measurement results. The equipment can be manufactured either as an autonomous sensor of automatic monitoring stations or as a standalone measuring device.

Claims (4)

PROTECTION REQUIREMENTS An infiltrometer and permeameter set with a metering pump, characterized in that it comprises a metering unit (2) for pumping water through the water distribution (5) with a water filter (4) either from the water source (6) to the application probe (1) or for pumping water from the application probe (1), a data logger (15) for archiving the operation data of the dosing unit (2), which is part of the control unit (3) together with the internal clock (16). Infiltration / permeameter / metering pump set according to claim 1, characterized in that, for switching the dosing unit (2), the power supply line (9) is connected to the control unit (3) by a level tip (7) and a leveling ground (8). tip. An infiltrometer and permeameter with metering pump assembly according to claims 1 and 2, further comprising a top cover (14) for eliminating vapor from the water surface within the application probe (1). Infiltration / permeameter / metering pump set according to claims 1 to 3, characterized in that it comprises a coarse sinter (18) in the water distribution (5) for filtering the pumped water or for sheathing the application probe (1).