1. The device for measuring the volume flow value of the gas-liquid two-phase flow of the aeration drip irrigation system is characterized by comprising a water storage tank (2), a first pipeline, a second pipeline, a third pipeline and a fourth pipeline,

the water storage tank (2) is communicated with the aeration equipment (1) through a pipeline, and the aeration equipment (1) is communicated with the second control valve (5) through a pipeline;

two ends of the first pipeline and the second pipeline are respectively communicated with the second control valve (5) and the fourth control valve (8), the first pipeline is provided with a first tee joint (11) and a first one-way valve (7), and the second pipeline is provided with a second tee joint (12) and a second one-way valve (9);

two ends of the third pipeline are respectively communicated with the first tee joint (11) and the water storage tank (2), and a water pump (3) and a first control valve (4) are arranged on the third pipeline;

two ends of the fourth pipeline are respectively communicated with the fourth control valve (8) and the volume flow meter (10), and the volume flow meter (10) is communicated with a field pipe network (14);

the third control valve (6) is communicated with one end of a drain pipe (13), the other end of the drain pipe (13) extends into the water storage tank (2), and the drain pipe (13) is provided with the third control valve (6);

the first control valve (4), the second control valve (5), the third control valve (6), the fourth control valve (8), the aeration equipment (1), the water pump (3) and the volume flow meter (10) are all electrically connected with the controller.

2. An aerated drip irrigation system gas-liquid two-phase flow volume flow value measuring device according to claim 1, characterized in that the first control valve (4), the second control valve (5), the third control valve (6) and the fourth control valve (8) are all solenoid valves.

3. An aeration drip irrigation system gas-liquid two-phase flow volume flow value measuring device according to claim 1, characterized in that the pipelines between the water storage tank (2) and the aeration equipment (1) and the water pump (3) are all provided with a filtering device (15);

the filter device comprises a filter element carrier (17) used for loading a filter element and end covers (16) arranged at two ends of the filter element carrier (17);

the end cap (16) comprises a first housing (161), a fluid nozzle (162) disposed on a side of the first housing (161), and a first groove (63) disposed on an inner wall of the first housing (161);

the filter element carrier (17) comprises a second shell (171), a central column (174) which is coaxially arranged with the second shell (171), a partition plate (172) which is arranged between the central column (174) and the second shell (171), and a second groove (173) which is arranged on the side surface of the second shell (171) and is matched with the first groove (163);

a cavity formed between the first groove (163) and the second groove (173) is filled with a sealing gasket (18); the filter element is filled in a cavity formed by the partition plate (172) and the inner wall of the second shell (171); the side surface of the second shell (171) is provided with a gland (19), and the gland (19) is provided with a through hole.

4. An aerated drip irrigation system gas-liquid two-phase flow volume flow value measuring device according to claim 3, wherein the cross-sections of the first housing (161) and the second housing (171) are both circular; the inner diameter of the first housing (161) is equal to the outer diameter of the second housing (171).

5. An aerated drip irrigation system gas-liquid two-phase flow volume flow value measuring device according to claim 3, wherein the groove depth of the first groove (163) is smaller than the groove depth of the second groove (173).

6. An aeration drip irrigation system gas-liquid two-phase flow volume flow value measuring device according to claim 3, characterized in that the end cover (16) and the filter element carrier (17) are connected through bolts.

7. An aerated drip irrigation system gas-liquid two-phase flow volume flow value measuring device according to claim 3, wherein the number of the partition plates (172) is four, four of the partition plates (172) form four cavities with the second housing (171), and the four cavities are filled with filter elements.

8. An aerated drip irrigation system gas-liquid two-phase flow volume flow value measuring device according to claim 7, wherein the filter element is a multi-layer folded filter membrane.

9. The measurement method of the gas-liquid two-phase flow volume flow value measurement device of the aerated drip irrigation system according to any one of the claims 1 to 8, characterized by comprising the following measurement steps:

s1, starting the aeration equipment (1), opening a third control valve (6), and enabling the gas-liquid two phases generated by the aeration equipment (1) to flow back to the water storage tank (2) through a drain pipe (13);

s2, opening the first control valve (4), and starting the water pump (3) until the water measured value passing through the volume flow meter (10) is changed and then stabilized;

stopping the water pump (3) and closing the first control valve (4);

the aeration equipment (1) is communicated with a first pipeline, and after the water measured value passing through the volume flow meter (10) is changed and then stabilized, the flow value of the volume flow meter (10) is recorded;

and S3, after the measurement is finished, the aeration equipment (1) is connected with the second pipeline, the third control valve (6) is closed, and the system works normally.

10. The measuring method of the gas-liquid two-phase flow volume flow rate value measuring device of the aerated drip irrigation system according to claim 9, wherein in S2, the mode of judging that the water measured value passing through the volume flow meter (10) changes before stabilizing is: the volume flow meter (10) returns a flow value to the controller every 1 second, and when the difference between the flow value of the previous second and the flow value of the next second is less than 1% for 3 times continuously, the volume flow meter (10) is stable in measurement.

Background

With the development of water-saving irrigation agriculture, aeration drip irrigation attracts wide attention as a novel efficient water-saving irrigation mode, and becomes an important development direction of water-saving irrigation. Because the gas quality is difficult to measure, the volume flow is one of the operation indexes which are needed urgently for measuring the gas-liquid two-phase flow of the aeration drip irrigation system, but due to the non-uniformity of the gas-liquid two-phase flow, the easy escape of the gas, the existence of a large amount of micro-nano bubbles and the like, the volume flow measurement of the gas-liquid two-phase flow under the aeration condition is always a difficult point in research, and the application and the development of the aeration drip irrigation are greatly limited.

Generally, the flow rate of the gas-liquid two-phase fluid is indirectly obtained mainly by two methods. The first method comprises the following steps: the mass flow of the water phase is measured by a weighing method, and the gas-water ratio is measured by a drainage method. And calculating by using the gas-water ratio of the two-phase flow and the mass flow of the water phase through a formula to obtain the volume flow of the two-phase flow. And the second method comprises the following steps: the volume of the gas phase and the volume of the liquid phase are respectively measured by separating the gas phase and the liquid phase of the gas-liquid two-phase flow with a certain volume in unit time, and the volume flow of the gas-liquid two-phase flow is obtained after addition and calculation. However, since a huge amount of micro-bubbles generated by aeration can exist stably in a water body for a long time, in order to separate a gas phase and a liquid phase relatively accurately or obtain a gas-water ratio by a drainage method, a long time is required to wait, and it cannot be determined whether all micro-bubbles in the water body are separated. Therefore, the two methods cannot measure the volume flow value of the two-phase flow in real time and have large errors. In addition, the gas-water ratio of the gas-liquid two-phase flow can also be reversely deduced by using an empirical formula. However, when the gas volume is reversely estimated according to the prior experience formula, the selection of the experience coefficient requires the operator to have rich experimental experience, and meanwhile, a certain error exists, and when the estimation of the volume flow is carried out, the error is amplified.

Therefore, the existing method is indirect measurement and complicated in operation, and the measurement result has large error.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a device and a method for measuring the volume flow value of gas-liquid two-phase flow of an aeration drip irrigation system, and aims to solve the problem of large error of a measurement result caused by the indirect measurement and complicated operation of the existing measurement mode.

In order to achieve the purpose, the invention adopts the following technical scheme:

the device for measuring the volume flow value of the gas-liquid two-phase flow of the aeration drip irrigation system comprises a water storage tank, a first pipeline, a second pipeline, a third pipeline and a fourth pipeline, wherein the water storage tank is communicated with aeration equipment, and the aeration equipment is communicated with a second control valve; two ends of the first pipeline are respectively communicated with the second control valve and the fourth control valve, and the first pipeline is provided with a first tee joint and a first one-way valve; two ends of the second pipeline are respectively communicated with the second control valve and the fourth control valve, and the second pipeline is sequentially provided with a second tee joint and a second one-way valve; two ends of a third pipeline are respectively communicated with the first tee joint and the water storage tank, and a water pump and a first control valve are arranged on the third pipeline; two ends of the fourth pipeline are respectively communicated with the fourth control valve and the volume flow meter, and the volume flow meter is communicated with the field pipe network; the third control valve is communicated with one end of the drain pipe, the other end of the drain pipe extends into the water storage tank, and the drain pipe is provided with the third control valve; the first control valve, the second control valve, the third control valve, the fourth control valve, the aeration equipment, the water pump and the volume flow meter are all electrically connected with the controller.

The invention has the beneficial effects that: in the scheme, compared with the first and second measurement modes mentioned in the background art, the measurement device does not need to separate gas from liquid, the fourth pipeline is filled with water without gas, then the gas-liquid two-phase liquid enters the fourth pipeline to discharge the water in the fourth pipeline, the measurement of the gas-liquid two-phase liquid is realized by measuring the flow of the discharged water, and the purpose of directly measuring the total volume flow value of the gas phase and the water phase is achieved; compared with the measurement mode through a calculation formula mentioned in the background art, the measurement device does not need to measure parameters such as gas-water ratio, water phase mass flow and the like respectively for calculation, and can directly measure the total volume flow value of gas phase and water phase; therefore, the volume flow value of the gas-liquid two-phase flow generated by the aeration equipment can be directly measured by the measuring device; the measuring device has simple structure and simple operation.

Further, the first control valve, the second control valve, the third control valve and the fourth control valve are all solenoid valves.

Furthermore, a filtering device is arranged on the pipeline between the water storage tank and the aeration equipment as well as the water pump;

the filter device comprises a filter element carrier for loading a filter element and end covers arranged at two ends of the filter element carrier;

the end cover comprises a first shell, a fluid pipe orifice arranged on the side surface of the first shell and a first groove arranged on the inner wall of the first shell;

the filter element carrier comprises a second shell, a central column which is coaxial with the second shell, a partition plate which is arranged between the central column and the second shell, and a second groove which is arranged on the side surface of the second shell and matched with the first groove;

a sealing gasket is filled between the first groove and the second groove; the filter element is filled in a cavity formed by the partition plate and the inner wall of the second shell; the side surface of the second shell is provided with a gland, and the gland is provided with a through hole.

Further, the cross sections of the first shell and the second shell are circular; the inner diameter of the first housing is equal to the outer diameter of the second housing.

Further, the groove depth of the first groove is smaller than the groove depth of the second groove.

Further, the end cover is connected with the filter element carrier through a bolt.

Furthermore, the number of the partition plates is four, four cavities are formed by the four partition plates and the second shell, and filter elements are filled in the four cavities.

Furthermore, the filter element is a multi-layer folded filter film.

The measuring method of the device for measuring the volume flow value of the gas-liquid two-phase flow of the aeration drip irrigation system comprises the following measuring steps:

s1, starting the aeration equipment, opening a third control valve, and enabling a gas-liquid phase generated by the aeration equipment to flow back to the water storage tank through a drain pipe;

s2, opening the first control valve, and starting the water pump until the water measured value passing through the volume flow meter is changed and then stabilized;

stopping the water pump and closing the first control valve;

the aeration equipment is communicated with the first pipeline, and after the water measured value passing through the volume flow meter is changed and stabilized, the flow value of the volume flow meter is recorded and is the sum of the volumes of the gas-liquid two-phase flow generated by the aeration equipment.

And S3, after the measurement is finished, the aeration equipment is connected with the second pipeline, the third control valve is closed, and the system works normally.

Further, in S2, the method of determining that the water measurement value passing through the volume flow meter changes before becoming stable is: the volume flow meter returns a flow value to the controller every 1 second, and when the difference between the flow value of the previous second and the flow value of the next second is less than 1% for 3 times, the measurement of the volume flow meter is stable.

In addition to the technical problems addressed by the present invention, the technical features constituting the technical solutions, and the advantageous effects brought by the technical features of the technical solutions described above, other technical problems that the present invention can solve, other technical features included in the technical solutions, and advantageous effects brought by the technical features will be described in further detail in the detailed description.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic connection diagram of a device for measuring the volume flow rate of a gas-liquid two-phase flow of an aeration drip irrigation system in the invention.

Fig. 2 is a schematic structural view of the filter device.

Fig. 3 is a cross-sectional view of a filter device.

Fig. 4 is an enlarged view of a in fig. 3.

Fig. 5 is a front view of the cartridge carrier.

Fig. 6 is a top view of a cartridge carrier.

Fig. 7 is a front view of the end cap.

Wherein: 1. an aeration device; 2. a water storage tank; 3. a water pump; 4. a first control valve; 5. a second control valve; 6. a third control valve; 7. a first check valve; 8. a fourth control valve; 9. a second one-way valve; 10. a volumetric flow meter; 11. a first tee joint; 12. a second tee joint; 13. a drain pipe; 14. field pipe network; 15. a filtration device; 16. an end cap; 161. a first housing; 162. a fluid orifice; 163. a first groove; 17. a filter element carrier; 171. a second housing; 172. a partition plate; 173. a second groove; 174. a central column; 18. a gasket; 19. and (7) pressing the cover.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-7, the present invention provides a device for measuring a volume flow value of a gas-liquid two-phase flow of an aeration drip irrigation system, which comprises a water storage tank 2, a first pipeline, a second pipeline, a third pipeline and a fourth pipeline, wherein the water storage tank 2 is communicated with an aeration device 1, and the aeration device 1 is communicated with a second control valve 5; two ends of the first pipeline are respectively communicated with the second control valve 5 and the fourth control valve 8, and the first pipeline is provided with a first tee joint 11 and a first one-way valve 7; two ends of the second pipeline are respectively communicated with the second control valve 5 and the fourth control valve 8, and the second pipeline is sequentially provided with a second tee joint 12 and a second one-way valve 9; two ends of a third pipeline are respectively communicated with the first tee joint 11 and the water storage tank 2, and a water pump 3 and a first control valve 4 are arranged on the third pipeline; two ends of the fourth pipeline are respectively communicated with the fourth control valve 8 and the volume flow meter 10, and the volume flow meter 10 is communicated with a field pipe network 14; the third control valve 6 is communicated with one end of a drain pipe 13, the other end of the drain pipe 13 extends into the water storage tank 2, and the drain pipe 13 is provided with the third control valve 6; the aeration equipment 1, the water pump 3 and the volume flow meter 10 are all electrically connected with the controller.

Compared with the second measurement mode mentioned in the background technology, the measurement device does not need to separate gas from liquid, and can directly measure the total volume flow value of the gas phase and the water phase; compared with the measurement mode through a calculation formula mentioned in the background art, the measurement device does not need to measure parameters such as gas-water ratio, water phase mass flow and the like respectively for calculation, and can directly measure the total volume flow value of gas phase and water phase; therefore, the volume flow value of the gas-liquid two-phase flow generated by the aeration equipment 1 can be directly measured by the measuring device; the measuring device has simple structure and simple operation.

The concrete connection relation of the scheme is as follows:

a first outlet of the water storage tank 2 is connected with an inlet of the aeration device 1, and an outlet of the aeration device 1 is communicated with an inlet of a second control valve 5; the second outlet of the water storage tank 2 is communicated with the inlet of the water pump 3, the outlet of the water pump 3 is communicated with the first interface of the first control valve 4, the second interface of the first control valve 4 is communicated with the first interface of the first tee joint 11, the second interface of the first tee joint 11 is communicated with the first outlet of the second control valve 5, the third interface of the first tee joint 11 is communicated with the inlet of the first one-way valve 7, the outlet of the first one-way valve 7 is communicated with the first inlet of the fourth control valve 8, the outlet of the fourth control valve 8 is communicated with the inlet of the volume flow meter 10, the second inlet of the fourth control valve 8 is communicated with the outlet of the second one-way valve 9, the inlet of the second one-way valve 9 is communicated with the first interface of the second tee joint 12, the second interface of the second tee joint 12 is communicated with the second outlet of the second control valve 5, the third interface of the second tee joint 12 is communicated with the first interface of the third control valve 6, and the second interface of the third control valve 6 is communicated with one end of the drain pipe 13, the other end of the drain pipe 13 is positioned in the water storage tank 2, and the outlet of the volume flow meter 10 is connected with a field pipe network 14.

Further, the first control valve 4, the second control valve 5, the third control valve 6, and the fourth control valve 8 are all solenoid valves.

In this scheme, the pipe diameter of first pipeline and second pipeline is the same with the pipe length, and the part model of the symmetry installation in position on first pipeline and the second pipeline is unanimous. In order to ensure the accurate measurement result, the fourth pipeline is a slender pipe or a long pipe or a thin pipe, and the fourth pipeline is preferably a slender pipe (a water pipe with a smaller pipe diameter and a longer length); according to the water conservation basic parameter testing method for the water conservation irrigation equipment, the flow velocity of water flow of a specified pipeline is less than or equal to 2.5m/s, the length of a fourth pipeline is less than or equal to 20m in practice according to calculation, and the device meets the requirements. When the flow volume of the gas-liquid two-phase flow is measured, more water is stored in the slender pipe, and even if the time for operating the controller exists in a worker, the water energy in the slender pipe can be ensured to meet the measurement.

And a filtering device is arranged on the pipeline between the water storage tank and the aeration equipment as well as between the water storage tank and the water pump.

Referring to fig. 2-7, the filter apparatus includes a cartridge carrier 17 for carrying the cartridge and end caps 16 mounted at both ends of the cartridge carrier 17; the end cap 16 includes a first housing 161, a fluid nozzle 162 provided on a side of the first housing 161, and a first groove 163 provided on an inner wall of the first housing 161; the cartridge carrier 17 includes a second case 171, a center post 174 coaxially disposed with the second case 171, a partition 172 disposed between the center post 174 and the second case 171, and a second groove 173 disposed on a side of the second case 171 and engaged with the first groove 163; the gasket 18 is filled between the first groove 163 and the second groove 173; the filter element is filled in a cavity formed by the partition plate 172 and the inner wall of the second shell 171; the second housing 171 has a cover 19 on a side thereof, and the cover 19 has a through hole.

Referring to fig. 3 and 4, the first and second housings 161 and 171 are circular in cross-section; the inner diameter of the first housing 161 is equal to the outer diameter of the second housing 171; the second shell 171 can be easily embedded on the inner wall of the first shell 161, and water leakage between the first shell 161 and the second shell 171 can be avoided.

The groove depth of the first groove 163 is smaller than the groove depth of the second groove 173; a gap is formed between the second groove 173 and the second groove 173; the seal 18 is preferably a rubber seal 18, and the seal 18 has a thickness slightly greater than the depth of the second groove 173. during installation, the end cap 16 is pressed by hand to compress the seal 18 into the gap, enhancing the seal.

Referring to fig. 4, the end cap 16 is bolted to the cartridge carrier 17 for easy removal.

The number of the partition plates 172 is four, four hollow cavities are formed by the four partition plates 172 and the second shell 171, and filter elements are filled in the four hollow cavities; the filter element is a multi-layer folded filter film.

In the present embodiment, there are two mounting manners for the partition plate 172, and in the first, referring to fig. 6, the partition plate 172 is vertically mounted on the inner wall of the second housing 171 and the central column 174; secondly, the partition plate 172 is obliquely installed on the inner wall of the second housing 171 and the center pillar 174, specifically, one side of the cover plate is fixed at a horizontal position of one side of the second housing 171, that is, at a horizontal position in fig. 6, and the other side of the cover plate is fixed at a vertical position of the other side of the second housing 171, that is, at a vertical position in fig. 6, so that the four cavities form an equal curved cavity, which has the advantage that after the filter element is filled, the contact between water and the filter element is increased, and the filtering capability of water is enhanced relative to the first one.

When the filter device is installed, the filter element is installed in the cavity; fixing the pressing plates on both sides of the second housing 171 to block the filter element; the annular packing 18 is placed in the second groove 173, the first housing 161 is fitted into the second housing 171, the first groove 163 is also fitted into the second groove 173, the packing 18 is filled in the space formed by the first groove 163 and the second groove 173 by pressing the end cap 16, the first housing 161 is fixed to the second housing 171 by bolts, and finally the fluid nozzle 162 is attached to the pipe.

It should be noted that the first groove 163 is circumferentially disposed on the inner wall of the first housing 161, and the second groove 173 is circumferentially disposed on the inner wall of the second housing 171, so that the first groove 163, the gasket 18 and the second groove 173 can only seal the interface between the first housing 161 and the second housing 171. The main function of the gland 19 is to prevent the filter element from being washed away with water from the cavity; the gland 19 may be a round cake, the radius of which is slightly smaller than the inner diameter of the second groove 173, a threaded hole may be formed in the middle of the central pillar 174 and the gland 19, and the gland 19 is fixed on the central pillar 174 by a bolt; a plurality of through holes are formed in the gland 19, so that water can enter or flow out of the filter element carrier 17 through the gland 19 conveniently. Fluid nozzle 162 is a fluid inlet or outlet. The partition 172 may be welded to the inner wall of the second housing 171 and the center post 174.

The filter device 15 has the following advantages:

when the filter paper or the filter screen is used for filtering, the filter paper or the filter screen cannot play a role in filtering and can leak water after being damaged; after the filter element of the filtering device 15 is abraded, although the filtering effect can not be achieved, the water leakage at the joint can be ensured; therefore, the filter device 15 is good for a filter paper or a filter net.

The inlet and outlet of the existing filter cannot play a role of filtering after being installed reversely, the filtering device 15 has no distinction of the inlet and outlet, and the filtering device 15 can avoid the harm caused by installation errors.

The sealing between the end cap 16 and the cartridge carrier 17 is achieved by the first groove 163, the second groove 173 and the sealing gasket 18, and when the filter cartridge is mounted, the sealing gasket 18 is pressed against the cavity formed by the first groove 163 and the second groove 173 by pressing the end cap 16 against the cartridge carrier 17, so that water is prevented from flowing out of the first groove 163 and the second groove 173.

The multi-layer folded filter membrane is filled in the cavity formed by the partition 172 and the second housing 171, and the water passing through the pressing cover 19 passes through the multi-layer folded filter membrane to maximize the contact area between the filter membrane and the water, so that impurities in the water can be well adsorbed.

A center post 174 is provided to facilitate installation of the baffle 172 and gland 19 and to facilitate replacement of the cartridge.

To sum up, the filter equipment 15 that sets up can the filtering get into the impurity of water pump 3 and aeration equipment 1 aquatic to extension aeration equipment 1 and water pump 3's life has avoided the measuring error because of the quality of water problem brings simultaneously, makes the flow volume that this scheme was measured more accurate.

The working principle of the measuring device in the scheme is as follows: when the volume flow of the gas-liquid two-phase flow in the second pipeline needs to be measured, a flow measuring program is started through the controller, and after the flow measuring program is finished, the numerical value displayed on the controller or the volume flow meter 10 is the volume flow value of the gas-liquid two-phase flow; and the aeration drip irrigation system recovers normal operation. Wherein the flow measurement procedures are S1 and S2 in the measurement method.

In conclusion, the measuring device is convenient to operate, the controller and the electromagnetic valve are arranged, and the operator controls the electromagnetic valve through the controller to automatically measure the volume value of the gas-liquid two-phase flow, so that the measuring result is more accurate. The controller may be a PLC controller. The volumetric flow meter 10 is preferably an electromagnetic volumetric flow meter 10.

The scheme also provides a measuring method of the device for measuring the volume flow value of the gas-liquid two-phase flow of the aeration drip irrigation system, which comprises the following measuring steps:

s1, starting the aeration device 1, opening the third control valve 6, and allowing the gas-liquid two-phase generated by the aeration device 1 to flow back to the water storage tank 2 through the drain pipe 13. In S1, the second inlet of the second control valve 5 and the first inlet of the fourth control valve 8 are opened so that the two-phase gas-liquid flow generated by the aeration apparatus 1 can be discharged only into the reservoir.

S2, opening the first control valve 4, and starting the water pump 3 until the water measured value passing through the volume flow meter 10 is changed and then stabilized; the water pump 3 is stopped and the first control valve 4 is closed.

At this time, the aeration device 1 is connected with the first pipeline, the water measured value passing through the volume flow meter 10 is changed and then stabilized, and then the flow value of the volume flow meter 10 is recorded, and at this time, the volume flow value of the volume flow meter 10 is equal to the volume flow value of the gas-liquid two-phase flow generated by the aeration device 1.

And S3, after the measurement is finished, the aeration equipment 1 is connected with the second pipeline, the third control valve 6 is closed, and the system works normally.

Specifically, in S2, the method of determining that the water measurement value passing through the volume flow meter 10 changes before becoming stable is: the volumetric flowmeter 10 returns a flow value to the controller every 1 second, when the difference between the flow value of the previous second and the flow value of the next second is less than 1% for 3 consecutive occurrences, this indicates that the volumetric flowmeter 10 is constantly measuring.

In the scheme, the field pipe network 14, the aeration equipment 1, the water pump 3, the electromagnetic valve, the volume flow meter 10 and the controller are all the prior art, and a person skilled in the art can directly find and use the technical scheme.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.