A performance test method for Venturi fertilizer applicator based on fertilizer pump

Abstract

The present invention proposes a performance test method of a Venturi fertilizer applicator based on a fertilizer pump. A fertilizer pump is configured in the fertilizer suction circuit to suck the mixed water-fertilizer mixture from the rear end of the mixing section of the water supply main pipeline. During the test, liquid fertilizer can be sucked from the fertilizer barrel through the Venturi fertilizer applicator, and after mixing, it is injected into the main pipeline from the front end of the mixing section for secondary mixing; the working pressure of the fertilizer applicator is adjusted by the water supply pump, and the inlet and outlet pressure difference is achieved by adjusting the flow rate of the fertilizer pump, and the two do not interfere with each other. Therefore, the working state of the Venturi fertilizer applicator during the performance test is consistent with the actual use, and the test effect is more practical.

Description

Technical Field

[0001] The present invention belongs to the technical field of integrated water and fertilizer technology, and particularly relates to a performance test method for a Venturi fertilizer applicator based on a fertilizer pump. Background Art

[0002] The integrated water and fertilizer technology is a new agricultural technology that combines irrigation and fertilization. It changes the traditional soil fertilization mode. Through a pumping and pressurizing system cooperating with a fertilizer tank for water and fertilizer mixing, and then conveying the water and fertilizer mixture to crops, it can control the irrigation water and fertilization amount to achieve the effects of timing and quantitative fertilization, water saving and fertilizer saving. The equipment for realizing this is called integrated water and fertilizer irrigation equipment. The Venturi fertilizer applicator is one of the key components. The irrigation water generates negative pressure through the Venturi fertilizer applicator to suck in and mix the liquid fertilizer evenly, and then irrigates and fertilizes the crops. The fertilizer applicator is the core of the integrated water and fertilizer irrigation equipment, and its performance mainly depends on the Venturi structure parameters and operating parameters such as the working water flow rate and working pressure. The performance test device for the Venturi fertilizer applicator can measure and calculate and analyze the working parameters and performance indicators such as the working flow rate, inlet pressure, outlet pressure, fertilizer suction port pressure, fertilizer suction amount, fertilizer suction flow ratio, head loss, and fertilizer suction efficiency of the Venturi fertilizer applicator, providing experimental verification for the optimal / optimized design of the Venturi fertilizer applicator.

[0003] In the existing performance test device for the Venturi fertilizer applicator, the working water of the fertilizer applicator is provided by a water supply pump. During the test, through the valve group (control valve 1 - control valve 5) in the test device, the working pressure and working flow rate of the fertilizer applicator are adjusted simultaneously. See the attached Figure 1 As is well known, the operating point (flow rate, head) of a pump is relatively fixed. It is relatively difficult to adjust the flow rate and head (working pressure) simultaneously as required by the test. The operation during the test is inconvenient and even some points cannot be adjusted. At the same time, because the working state of the fertilizer applicator is inconsistent with the actual working scenario, test deviations may be generated, affecting the test results and directly affecting the optimal / optimized design work of the Venturi fertilizer applicator. Summary of the Invention

[0004] Aiming at the defects and deficiencies of the existing technology, the purpose of the present invention is to provide a performance test method for a Venturi fertilizer applicator based on a fertilizer pump. The loop structure of the existing performance test device for the Venturi fertilizer applicator is adjusted, and then the design of the entire performance test method is reconstructed and optimized. A fertilizer pump is configured in the fertilizer suction loop to suck in the mixed water and fertilizer mixture from the rear end of the mixing section of the water supply main pipeline. At the same time, the vast majority of valve settings in the existing device are simplified and cancelled, so that when the test is carried out, the liquid fertilizer can be sucked from the fertilizer tank through the Venturi fertilizer applicator, and after mixing, it is injected into the main pipeline from the front end of the mixing section for secondary mixing. Thus, the working state during the performance test of the Venturi fertilizer applicator is consistent with the actual use, and the test effect is more practical.

[0005] In the present invention, the working pressure of the fertilizer applicator is adjusted by a water supply pump, while the differential pressure between the inlet and outlet is achieved by adjusting the flow rate of the fertilizer pump (the working flow rate of the fertilizer applicator). The two do not interfere with each other, and the test adjustment and control are convenient and accurate.

[0006] The present invention specifically adopts the following technical solutions:

[0007] A method for testing the performance of a Venturi fertilizer applicator based on a fertilizer pump, characterized in that: a fertilizer pump is configured in the fertilizer suction circuit to suck the mixed water and fertilizer mixture from the rear end of the mixing section of the water supply main pipeline, so that when conducting the test, liquid fertilizer can be sucked from the fertilizer bucket through the Venturi fertilizer applicator, and after mixing, it is injected into the main pipeline from the front end of the mixing section for secondary mixing; the working pressure of the fertilizer applicator is adjusted by a water supply pump, and the differential pressure between the inlet and outlet is achieved by adjusting the flow rate of the fertilizer pump, and the two do not interfere with each other.

[0008] Furthermore, the water supply pump provides constant-pressure working water for the Venturi fertilizer applicator; the working pressure of the Venturi fertilizer applicator is adjusted by the water supply pump and a first regulating valve provided at the water outlet end; the fertilizer suction amount of the Venturi fertilizer applicator is the measured flow rate of the first flowmeter minus the measured flow rate of the second flowmeter, and the first flowmeter and the second flowmeter are respectively installed on the fertilizer suction branch pipes on both sides of the Venturi fertilizer applicator; the working flow rate of the fertilizer applicator is adjusted by a second regulating valve provided on the fertilizer suction branch pipe beside the fertilizer pump, so as to measure the working parameters and performance indicators of the fertilizer applicator under different working flow rates at the same working pressure.

[0009] Furthermore, a third flowmeter is provided at the water inlet section of the main pipeline; pressure sensors are respectively provided on the pipelines at both ends of the water supply pump, at three ends of the Venturi fertilizer applicator, and at both ends of the fertilizer pump.

[0010] Furthermore, the working pressure of the Venturi fertilizer applicator is divided into 5 levels: 10m, 15m, 20m, 25m, and 30m; the flow rate of the fertilizer pump is adjusted point by point and the working pressure of the Venturi fertilizer applicator is maintained within ±0.1m of the set pressure level. After stabilization, the measurement data of each flowmeter and pressure sensor are collected through a data acquisition system; observe the water flow state in the transparent pipe at the outlet of the Venturi fertilizer applicator. When vaporization appears and develops to the point where the working parameters of the fertilizer applicator cannot return to stability, end the performance test at this pressure point; repeat the above process until all pressure point tests are completed normally, and the test ends and a performance test data record form is generated.

[0011] Furthermore, the data analysis and processing specifically include the following steps:

[0012] Step S1: According to the performance test data of the Venturi fertilizer applicator, calculate the differential pressure between the inlet and outlet of the Venturi fertilizer applicator and the fertilizer suction amount, and draw the fertilizer suction characteristic curve of the Venturi fertilizer applicator;

[0013] Step S2: According to the fertilizer suction characteristic curve of the Venturi fertilizer applicator, calculate the performance parameters and indexes of the Venturi fertilizer applicator under different working pressures, and draw the performance curve of the Venturi fertilizer applicator.

[0014] Step S3: Analyze and study the fertilizer suction characteristic curve and performance curve of the Venturi fertilizer applicator, verify the numerical simulation results of the Venturi fertilizer applicator, and guide the optimal design of the Venturi fertilizer applicator.

[0015] Further, in Step S1, the fertilizer suction characteristic curve of the Venturi fertilizer applicator includes the fertilizer suction amount - inlet and outlet pressure difference curve and the working flow rate - inlet and outlet pressure difference curve.

[0016] Further, in Step S2, the performance parameters and indexes include: critical flow rate, critical pressure difference, extreme flow rate, extreme pressure difference, maximum fertilizer suction amount, fertilizer suction flow rate ratio, head loss, and fertilizer suction efficiency; the performance curve of the Venturi fertilizer applicator includes: one or more of the critical pressure difference - working pressure curve, extreme pressure difference - working pressure curve, critical flow rate - working pressure curve, extreme flow rate - working pressure curve, maximum fertilizer suction amount - working pressure curve, fertilizer suction flow rate ratio - working pressure curve, and fertilizer suction efficiency - working pressure curve.

[0017] Further, in Step S3, horizontally compare the normal fertilizer suction working flow rate region, maximum fertilizer suction amount, fertilizer suction flow rate ratio, head loss, and fertilizer suction efficiency parameters and performance indexes of each Venturi fertilizer applicator to guide the optimal design work of the Venturi fertilizer applicator.

[0018] Compared with the prior art, in the present invention and its preferred scheme, the working pressure of the fertilizer applicator is adjusted by a water supply pump, while the inlet and outlet pressure difference is achieved by adjusting the flow rate of the fertilizer pump (the working flow rate of the fertilizer applicator), and the two do not interfere with each other. The test adjustment and control are convenient and accurate. Its simulation of the working state during the performance test of the Venturi fertilizer applicator is more accurate, the operation and use are significantly simpler, and its guiding role for the optimal design of the Venturi fertilizer applicator is more significant.

[0019] A fertilizer pump is configured in the fertilizer suction circuit of the performance test device of the Venturi fertilizer applicator to adjust the working flow rate of the fertilizer applicator; in terms of the data processing and analysis method, starting from the fertilizer suction characteristic curve of the Venturi fertilizer applicator, performance parameters and indexes such as critical flow rate, extreme flow rate, fertilizer suction flow rate ratio, and fertilizer suction efficiency are proposed, and the corresponding performance curves are drawn to verify and evaluate the performance of the Venturi fertilizer applicator, which has high practical value and promotion prospects. Brief Description of the Drawings

[0020] The following further details the present invention in conjunction with the drawings and specific embodiments:

[0021] Figure 1 It is a schematic diagram of the performance test device of the Venturi fertilizer applicator without a fertilizer pump in the prior art.

[0022] In the figure: 101 - water supply pump; 102 - regulating valve 1; 103 - flowmeter 1; 104 - pressure sensor 1; 105 - regulating valve 2; 106 - pressure sensor 2; 107 - regulating valve 3; 108 - flowmeter 2; 109 - regulating valve 4; 110 - Venturi fertilizer applicator; 111 - fertilizer tank; 112 - flowmeter 3; 113 - regulating valve 5.

[0023] Figure 2 It is a schematic structural diagram of a Venturi fertilizer applicator performance test device provided by an embodiment of the present invention based on a fertilizer pump.

[0024] In the figure: 1 - first pressure sensor; 2 - water supply pump; 3 - filter; 4 - second pressure sensor; 5 - third flowmeter; 6 - mixing section; 7 - first regulating valve; 8 - second flowmeter; 9 - third pressure sensor; 10 - fourth pressure sensor; 11 - fertilizer tank; 12 - Venturi fertilizer applicator; 13 - fifth pressure sensor; 14 - sixth pressure sensor; 15 - fertilizer pump; 16 - seventh pressure sensor; 17 - first flowmeter; 18 - second regulating valve; 19 - data acquisition system.

[0025] Figure 3 It is a schematic diagram of the fertilizer absorption characteristic curve of the Venturi fertilizer applicator according to an embodiment of the present invention.

[0026] Figure 4 It is a schematic diagram of the relationship curve between the critical pressure difference, extreme pressure difference and working pressure according to an embodiment of the present invention.

[0027] Figure 5 It is a schematic diagram of the relationship curve between the critical flow rate, extreme flow rate, maximum fertilizer absorption amount and working pressure according to an embodiment of the present invention.

[0028] Figure 6 It is a schematic diagram of the performance curves of the fertilizer absorption flow ratio and fertilizer absorption efficiency according to an embodiment of the present invention. Detailed implementation manners

[0029] To make the features and advantages of this patent more obvious and understandable, specific embodiments are given below and described in detail as follows:

[0030] As Figure 1As shown in the figure, in the performance test device of the Venturi fertilizer applicator without a fertilizer pump provided by the prior art, it includes a main pipeline and a fertilizer suction branch pipe that are connected. It includes components such as a water supply pump 101, a regulating valve 1 102, a flow meter 1 103, a pressure sensor 1104, a regulating valve 2 105, a pressure sensor 2 106, a regulating valve 3 107, a flow meter 2 108, a regulating valve 4 109, a Venturi fertilizer applicator 110, a fertilizer bucket 111, a flow meter 3 112, a regulating valve 5 113, etc. During the test, through the valve group (regulating valves 1 to 5) in the test device, the working pressure and working flow of the fertilizer applicator are adjusted simultaneously. As is well known, the operating point (flow rate, head) of a pump is relatively fixed. It is relatively difficult to adjust the flow rate and head (working pressure) randomly at the same time as required by the test. The operation is inconvenient during the test and some points cannot even be adjusted; at the same time, since the working state of the fertilizer applicator is inconsistent with the actual working scenario, test deviations may occur, affecting the test results and directly affecting the optimal / optimized design work of the Venturi fertilizer applicator.

[0031] As Figure 2 As shown in the figure, this embodiment is improved on the basis of the above structure. The core purpose of its design is to configure a fertilizer pump 15 in the fertilizer suction circuit, suck the mixed water and fertilizer mixture from the rear end of the mixing section of the water supply main pipeline, suck the liquid fertilizer from the fertilizer bucket through the Venturi fertilizer applicator, and inject it into the main pipeline from the front end of the mixing section for secondary mixing after mixing, so that the working state during the performance test of the Venturi fertilizer applicator is consistent with the actual use, and the test effect is more practical; the working pressure of the fertilizer applicator is adjusted by the water supply pump, and the differential pressure between the inlet and outlet is achieved by adjusting the flow rate of the fertilizer pump (the working flow rate of the fertilizer applicator). The two do not interfere with each other, and the test adjustment and control are convenient and accurate.

[0032] Specifically, in the solution provided by this embodiment: also based on the connected main pipeline and fertilizer suction branch pipe, the test device mainly consists of: a water supply pump 2, a filter 3, a mixing section 6, a fertilizer pump 15, a Venturi fertilizer applicator 12, a fertilizer bucket 11, regulating valves (including a first regulating valve 7, a second regulating valve 18), flow meters (including: a first flow meter 17, a second flow meter 8, a third flow meter 5), pressure sensors (including: a first pressure sensor 1, a second pressure sensor 4, a third pressure sensor 9, a fourth pressure sensor 10, a fifth pressure sensor 13, a sixth pressure sensor 14, a seventh pressure sensor 16) and a data acquisition system 19, etc.

[0033] Among them, the water supply pump 1 is a variable-frequency constant-pressure water supply pump, which provides constant-pressure working water for the Venturi fertilizer applicator 12; the working pressure (inlet pressure) of the Venturi fertilizer applicator is adjusted by the water supply pump 1 and the first regulating valve 7; it can be divided into 5 levels: 10m, 15m, 20m, 25m, and 30m.

[0034] The fertilizer application pump 15 is a small multi-stage centrifugal electric pump. Its function is to suck the mixed water-fertilizer mixture from the rear end of the mixing section 6 of the main water supply pipeline, suck the liquid fertilizer from the fertilizer tank 11 through the Venturi fertilizer applicator 12, and after mixing, inject it into the main pipeline from the front end of the mixing section for secondary mixing, so that the working state of the Venturi fertilizer applicator is consistent with the actual use. And in this solution, the setting requirement for the regulating valve is greatly reduced compared with the prior art. In particular, there is no need to set a regulating valve on the mixing section of the main pipeline.

[0035] In this solution, the fertilizer absorption amount of the Venturi fertilizer applicator is the measured flow rate of the first flow meter 17 minus the measured flow rate of the second flow meter 8, so that it can be accurately collected, calculated and controlled; the working flow rate of the fertilizer applicator can be adjusted by the second regulating valve 18, so that the working parameters and performance indicators of the fertilizer applicator under different working flow rates at the same working pressure can be measured.

[0036] In the data acquisition system 19 in this embodiment, the corresponding equipment in the prior art can be directly adopted in terms of hardware, such as the system composed of a single-chip microcomputer-PC host computer. By measuring each flow meter and pressure sensor in the system, parameters and performance indicators such as the working flow rate, inlet pressure, outlet pressure, fertilizer absorption port pressure, fertilizer absorption amount, fertilizer absorption flow ratio, head loss and fertilizer absorption efficiency of the Venturi fertilizer applicator are measured and calculated and analyzed to complete the performance test of the Venturi fertilizer applicator.

[0037] Based on the above design, the performance test method of the Venturi fertilizer applicator based on the fertilizer application pump in this embodiment can be constructed:

[0038] In the performance test, through the data acquisition module, the working pressure of the Venturi fertilizer applicator is set to 5 pressure levels of 10, 15, 20, 25, and 30 m. The flow rate of the fertilizer application pump is adjusted point by point and the working pressure of the Venturi fertilizer applicator is maintained within ±0.1 m of the set pressure level. After stabilization, the measurement data of each flow meter and pressure sensor are collected through the human-computer interaction of the data acquisition system; observe the water flow state in the transparent pipe at the outlet of the Venturi fertilizer applicator. When vaporization appears and develops to the point where the working parameters of the fertilizer applicator cannot be restored to stability, end the performance test at this pressure point; repeat the above process until all pressure point tests are completed normally. The test ends and a performance test data record form is generated, and its format is shown in Table 1 for details.

[0039] Furthermore, data analysis and processing are carried out through the data processing and analysis module.

[0040] First, according to the performance test data of the Venturi fertilizer applicator (its format is shown in Table 1 for details), calculate the pressure difference between the inlet and outlet of the Venturi fertilizer applicator and the fertilizer absorption amount, and draw the fertilizer absorption characteristic curve of the Venturi fertilizer applicator, that is, fertilizer absorption amount - pressure difference between inlet and outlet, working flow rate - pressure difference between inlet and outlet, as shown in Figure 3Secondly, according to the fertilizer suction characteristic curve of the Venturi fertilizer applicator, through data processing, analysis and calculation, performance parameters and indexes such as the critical flow rate, critical pressure difference, extreme flow rate, extreme pressure difference, maximum fertilizer suction amount, fertilizer suction flow ratio, head loss and fertilizer suction efficiency of the Venturi fertilizer applicator under different working pressures are obtained (the specific format is shown in Table 2), and the performance curve of the Venturi fertilizer applicator is drawn, namely the critical pressure difference - working pressure, extreme pressure difference - working pressure, critical flow rate - working pressure, extreme flow rate - working pressure, maximum fertilizer suction amount - working pressure, fertilizer suction flow ratio - working pressure and fertilizer suction efficiency - working pressure, as shown in Figure 4 , Figure 5 , Figure 6 ; Finally, analyze and study the fertilizer suction characteristic curve and performance curve of the Venturi fertilizer applicator, verify the numerical simulation results of the Venturi fertilizer applicator, and guide the optimal design of the Venturi fertilizer applicator; horizontally compare the normal fertilizer suction working flow area, maximum fertilizer suction amount, fertilizer suction flow ratio, head loss and fertilizer suction efficiency and other parameters and performance indexes of each Venturi fertilizer applicator to guide the optimal design work of the Venturi fertilizer applicator.

[0041] Table 1 Record Table of Original Data of Performance Test of Venturi Fertilizer Applicator

[0042]

[0043] Table 2 Summary Table of Test Data Analysis and Processing

[0044]

[0045] In summary, in this embodiment, a fertilizer pump is configured in the fertilizer suction circuit of the performance test device of the Venturi fertilizer applicator to adjust the working flow rate of the fertilizer applicator; in terms of data processing and analysis methods, starting from the fertilizer suction characteristic curve of the Venturi fertilizer applicator, performance parameters and indexes such as critical flow rate, extreme flow rate, fertilizer suction flow ratio and fertilizer suction efficiency are proposed, and the corresponding performance curves are drawn to verify and evaluate the performance of the Venturi fertilizer applicator and guide the optimal design work of the Venturi fertilizer applicator. It overcomes the deficiencies in the existing technology and provides a performance test method for the Venturi fertilizer applicator with a relatively high degree of automation, high test accuracy, simple operation and use, data processing system and professionalism.

[0046] This patent is not limited to the above best implementation manner. Anyone can obtain various other forms of a performance test method for a Venturi fertilizer applicator based on a fertilizer pump under the inspiration of this patent. All equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope covered by this patent.

Claims

1. A performance test method for a Venturi fertilizer applicator based on a fertilizer pump, characterized in that: A fertilizer pump is configured in the fertilizer suction circuit to suck the mixed water-fertilizer mixture from the rear end of the mixing section of the main water supply pipeline, so that when conducting the test, the liquid fertilizer can be sucked from the fertilizer bucket through the Venturi fertilizer applicator, and after mixing, it is injected into the main pipeline from the front end of the mixing section for secondary mixing; the working pressure of the fertilizer applicator is adjusted by the water supply pump, and the differential pressure between the inlet and outlet is achieved by adjusting the flow rate of the fertilizer pump, and the adjustment of the working pressure and the differential pressure between the inlet and outlet of the fertilizer applicator do not interfere with each other; The water supply pump provides constant-pressure working water for the Venturi fertilizer applicator; the working pressure of the Venturi fertilizer applicator is adjusted by the water supply pump and the first regulating valve arranged at the water outlet end; the fertilizer suction amount of the Venturi fertilizer applicator is the measured flow rate of the first flowmeter minus the measured flow rate of the second flowmeter, and the first flowmeter and the second flowmeter are respectively installed on the fertilizer suction branch pipes on both sides of the Venturi fertilizer applicator; the working flow rate of the fertilizer applicator is adjusted by the second regulating valve arranged on the fertilizer suction branch pipe beside the fertilizer pump, so as to measure the working parameters and performance indicators of the fertilizer applicator at different working flow rates under the same working pressure.

2. A performance test method for a Venturi fertilizer applicator based on a fertilizer pump according to claim 1, characterized in that: A third flowmeter is arranged at the water inlet section of the main pipeline; pressure sensors are respectively arranged on the pipelines at both ends of the water supply pump, at the three ends of the Venturi fertilizer applicator, and at both ends of the fertilizer pump.

3. A performance test method for a Venturi fertilizer applicator based on a fertilizer pump according to claim 2, characterized in that: The working pressure of the Venturi fertilizer applicator is divided into 5 levels: 10m, 15m, 20m, 25m, and 30m; adjust the flow rate of the fertilizer pump point by point and keep the working pressure of the Venturi fertilizer applicator within ±0.1m of the set pressure level. After stabilization, collect the measurement data of each flowmeter and pressure sensor through the data acquisition system; observe the water flow state in the transparent pipe at the outlet of the Venturi fertilizer applicator. When vaporization appears and develops to the point where the working parameters of the fertilizer applicator cannot be restored to stability, end the performance test at this pressure point; repeat the above process until all pressure point tests are completed normally, and the test ends and a performance test data record form is generated.

4. A performance test method for a Venturi fertilizer applicator based on a fertilizer pump according to claim 3, characterized in that: The data analysis and processing specifically include the following steps: Step S1: According to the performance test data of the Venturi fertilizer applicator, calculate the differential pressure between the inlet and outlet of the Venturi fertilizer applicator and the fertilizer suction amount, and draw the fertilizer suction characteristic curve of the Venturi fertilizer applicator; Step S2: According to the fertilizer suction characteristic curve of the Venturi fertilizer applicator, calculate the performance parameters and indicators of the Venturi fertilizer applicator under different working pressures, and draw the performance curve of the Venturi fertilizer applicator; Step S3: Analyze and study the fertilizer suction characteristic curve and performance curve of the Venturi fertilizer applicator, verify the numerical simulation results of the Venturi fertilizer applicator, and guide the optimization design of the Venturi fertilizer applicator.

5. A performance test method for a Venturi fertilizer applicator based on a fertilizer pump according to claim 4, characterized in that: In step S1, the fertilizer suction characteristic curve of the Venturi fertilizer applicator includes the fertilizer suction amount - inlet and outlet pressure difference curve and the working flow rate - inlet and outlet pressure difference curve.

6. A performance test method for a Venturi fertilizer applicator based on a fertilizer pump according to claim 5, characterized in that: In step S2, the performance parameters and indicators include: critical flow rate, critical pressure difference, extreme flow rate, extreme pressure difference, maximum fertilizer suction amount, fertilizer suction flow ratio, head loss, and fertilizer suction efficiency; the performance curve of the Venturi fertilizer applicator includes: one or more of the critical pressure difference - working pressure curve, extreme pressure difference - working pressure curve, critical flow rate - working pressure curve, extreme flow rate - working pressure curve, maximum fertilizer suction amount - working pressure curve, fertilizer suction flow ratio - working pressure curve, and fertilizer suction efficiency - working pressure curve.

7. A performance test method for a Venturi fertilizer applicator based on a fertilizer pump according to claim 6, characterized in that: In step S3, horizontally compare the parameters and performance indicators of the normal fertilizer suction working flow rate area, maximum fertilizer suction amount, fertilizer suction flow ratio, head loss, and fertilizer suction efficiency of each Venturi fertilizer applicator to guide the design work of the Venturi fertilizer applicator.

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