A method and device for evaluating atomization performance of a pressure nozzle

Abstract

The present invention provides a method and device for evaluating the atomization performance of a pressure nozzle, relating to the technical field of atomization performance testing. The method comprises: first determining the total volume and total kinetic energy of the droplets when the pressure nozzle is spraying, and calculating the cavity pressure of the pressure nozzle using the inlet flow rate of the liquid inside the pressure nozzle pipe and the nozzle flow rate at the nozzle. Then, the initial energy of the pressure nozzle under the weighted volume is calculated in combination with the total volume of the droplets, and the ratio of the total kinetic energy of the droplets to the initial energy is used as the atomization performance index of the pressure nozzle. The present invention solves the problem that the spray performance evaluation method of the pressure nozzle in the prior art lacks universality and is difficult to directly and accurately evaluate the atomization performance of the pressure nozzle, and provides a new technical method for the performance evaluation and selection of pressure nozzles.

Description

Technical Field

[0001] The present invention relates to the technical field of atomization performance testing, and in particular to a method and device for evaluating the atomization performance of a pressure nozzle. Background Art

[0002] In applications such as agricultural plant protection, industrial spraying, and firefighting, pressure sprinklers, with their unique design and operating principles, play a vital role in improving agricultural production efficiency and resource utilization. The spray efficiency of pressure sprinklers directly impacts operational quality and energy efficiency. Atomization performance, a core metric for evaluating sprinkler performance, reflects the efficiency with which liquid kinetic energy is converted into droplet kinetic energy.

[0003] The existing technology for evaluating the spray performance of pressure nozzles relies primarily on experimental measurements and theoretical analysis, primarily including the following: First, optical measurement methods, such as laser particle size analyzers, PIV particle image velocimeters, and laser Doppler velocimeters, are used to measure the particle size and velocity distribution of droplets. Second, theoretical calculation methods, which use a mathematical model of the flow and spray within the nozzle and combine it with the principles of fluid mechanics and thermodynamics to predict spray performance. Third, empirical evaluation methods, which use a large amount of experimental data to develop empirical formulas for nozzle spray performance. None of these methods are universally applicable, and they struggle to directly and accurately evaluate the spray performance of pressure nozzles, failing to provide strong support for the optimal design and selection of pressure nozzles. Summary of the Invention

[0004] The present invention provides a method and device for evaluating the atomization performance of a pressure nozzle, which are used to solve the problem that the spray performance evaluation method of a pressure nozzle in the prior art is not universal enough and it is difficult to directly and accurately evaluate the atomization performance of a pressure nozzle.

[0005] The present invention provides a method for evaluating the atomization performance of a pressure nozzle, comprising:

[0006] Determine the total volume of droplets and the total kinetic energy of droplets when spraying from a pressure nozzle;

[0007] Obtaining the inlet flow rate of the liquid inside the pressure nozzle pipe and the nozzle flow rate at the nozzle;

[0008] Calculating the cavity pressure of the pressure nozzle according to the inlet flow rate and the nozzle flow rate;

[0009] The initial energy of the pressure nozzle under weighted volume is calculated based on the cavity pressure, the inlet flow rate and the total volume of the droplets, and the ratio of the total kinetic energy of the droplets to the initial energy is used as the atomization performance index of the pressure nozzle.

[0010] In some embodiments, the process of determining the total volume of droplets when the pressure nozzle sprays includes:

[0011] When the pressure nozzle is spraying, the particle size of a single droplet collected by a phase Doppler particle analyzer is obtained, and the volume of the single droplet is calculated based on the particle size;

[0012] Determine the total number of droplets during spraying based on the number of effective droplets collected at droplet measurement points within the spray width, wherein the droplet measurement points are evenly distributed within the spray width;

[0013] The volumes of individual droplets of the total number of droplets are summed to obtain the total volume of droplets when the pressure nozzle is spraying.

[0014] In some embodiments, the process of determining the total kinetic energy of droplets when the pressure nozzle sprays includes:

[0015] Within the spray width range, a corresponding position weight is assigned to each droplet measurement point, wherein the position weight of each droplet measurement point is negatively correlated with the actual distance from the pressure nozzle;

[0016] After the pressure nozzle sprays, for each droplet collected at the droplet measurement point, a first velocity in the horizontal direction and a second velocity in the vertical direction are determined respectively;

[0017] At each droplet measurement point, calculating the theoretical spray kinetic energy of each droplet according to the first velocity and the second velocity, and performing weighted calculation on the theoretical spray kinetic energy using a position weight to obtain the actual spray kinetic energy of the droplet;

[0018] The actual spray kinetic energy of each droplet measurement point is summed to obtain the total kinetic energy of the droplets when the pressure nozzle is spraying.

[0019] In some embodiments, obtaining the inlet flow rate of the liquid inside the pressure nozzle pipe and the nozzle flow rate at the nozzle includes:

[0020] Obtain the liquid flow inside the pressure nozzle collected by the electromagnetic flowmeter;

[0021] Calculate the inlet cross-sectional area and nozzle cross-sectional area of ​​the pressure nozzle respectively;

[0022] The ratio of the liquid flow rate to the inlet cross-sectional area is used as the inlet flow rate of the liquid inside the pressure nozzle pipeline, and the ratio of the liquid flow rate to the nozzle cross-sectional area is used as the nozzle flow rate of the liquid at the nozzle of the pressure nozzle.

[0023] In some embodiments, the calculating the cavity pressure of the pressure nozzle according to the inlet flow rate and the nozzle flow rate includes:

[0024] Determining the pressure loss of the liquid during the flow in the pressure nozzle pipeline, wherein the pressure loss includes the friction loss determined by the Darcy friction coefficient and the local loss determined by the local loss coefficient;

[0025] Calculating the total inlet pressure of the pressure nozzle according to the pipeline pressure of the pressure nozzle and the inlet flow rate, and determining the total nozzle pressure of the pressure nozzle according to the unknown outlet pressure of the pressure nozzle, the nozzle flow rate and the pressure loss;

[0026] Constructing a modified Bernoulli equation based on the inlet total pressure and the nozzle total pressure;

[0027] The modified Bernoulli equation is solved, and the unknown outlet pressure obtained by the solution is used as the cavity pressure of the pressure nozzle.

[0028] In some embodiments, the calculating the initial energy of the pressure nozzle under the weighted volume based on the cavity pressure, the inlet flow rate, and the total volume of the droplets includes:

[0029] Calculating the inlet kinetic energy of the liquid inside the pressure nozzle according to the inlet flow rate and the total volume of the droplets;

[0030] Calculating the pressure energy of the liquid inside the pressure nozzle according to the cavity pressure and the total volume of the droplets;

[0031] The inlet kinetic energy and the pressure energy are summed to obtain the initial energy of the corresponding weighted volume inside the pressure nozzle.

[0032] The present invention also provides a device for evaluating the atomization performance of a pressure nozzle, comprising:

[0033] A determination module, used to determine the total volume of droplets and the total kinetic energy of droplets when the pressure nozzle is spraying;

[0034] An acquisition module is used to acquire the inlet flow rate of the liquid inside the pressure nozzle pipeline and the nozzle flow rate at the nozzle;

[0035] a calculation module, configured to calculate the cavity pressure of the pressure nozzle according to the inlet flow rate and the nozzle flow rate;

[0036] An evaluation module is used to calculate the initial energy of the pressure nozzle under weighted volume based on the cavity pressure, the inlet flow rate and the total volume of the droplets, and use the ratio of the total kinetic energy of the droplets to the initial energy as the atomization performance index of the pressure nozzle.

[0037] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the atomization performance evaluation method of the pressure nozzle as described above is implemented.

[0038] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the atomization performance evaluation method of any of the pressure nozzles described above is implemented.

[0039] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the atomization performance evaluation method of any of the pressure nozzles described above is implemented.

[0040] The atomization performance evaluation method and device for a pressure nozzle provided by the present invention calculate the atomization performance index by calculating the initial energy of the pressure nozzle under the weighted volume and the total kinetic energy of the droplets. As a comprehensive evaluation index for evaluating pressure nozzles, it can comprehensively reflect the spray performance of the pressure nozzle, provide strong support for the optimal design and selection of the pressure nozzle, and the comprehensive evaluation index can be applied to the spray performance evaluation of different types of pressure nozzles, and has good universality. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced one by one below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 It is a flow chart of the atomization performance evaluation method of the pressure nozzle provided by the present invention.

[0043] Figure 2 It is a schematic diagram of the principle of the method for evaluating the atomization performance of the pressure nozzle provided by the present invention.

[0044] Figure 3 It is a structural schematic diagram of the atomization performance evaluation device of the pressure nozzle provided by the present invention.

[0045] Figure 4 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0046] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0047] The following describes the atomization performance evaluation method and device of the pressure nozzle of the present invention with reference to the accompanying drawings. Figure 1 FIG. 1 is a flow chart of a method for evaluating the atomization performance of a pressure nozzle provided by the present invention, as shown in FIG. Figure 1 As shown, the method includes the following steps 101 to 104, which are described in detail below.

[0048] Step 101: Determine the total volume of droplets and the total kinetic energy of droplets when the pressure nozzle is spraying.

[0049] like Figure 2 As shown, Figure 2 The diagram shows the pressure nozzle spraying. When the pressure nozzle is spraying, multiple droplet measurement points are set at a distance of L meters in the vertical direction of the nozzle. Figure 2 The example shows 10 droplet measurement points. The sprayed liquid can be tap water, pesticides, or other liquids. A phase Doppler particle analyzer is installed at each droplet measurement point. By adjusting the spatial angle between the laser emitter and the receiver, the measurement area at the droplet measurement point covers the core spray area of ​​the pressure nozzle, and a flashing green stripe can be clearly seen through the receiver slit. The laser wavelength, sampling frequency, and particle size detection range of the phase Doppler particle analyzer are set based on the nozzle type (fan / conical) and the physical properties of the solution. Calibration is performed using standard particle sizes to verify that the particle size measurement error is ≤±2% and the velocity measurement error is ≤±0.5 m / s. After the pressure nozzle starts spraying and the pressure stabilizes, the phase Doppler particle analyzer simultaneously collects the droplet size and two-dimensional velocity vector on a horizontal plane at a distance L from the nozzle. During the acquisition process, the phase Doppler particle analyzer is moved to the specific droplet measurement point using a three-axis positioning system to collect droplet parameters. The spray control system provides stable in-pipe pressure and flow rate and monitors the pressure and liquid flow rate in real time. Ultimately, in a single sampling cycle, data for n valid particles can be collected, and droplet parameters are evenly collected at m droplet measurement points, resulting in a total of N valid droplets. Threshold filtering (signal-to-noise ratio > 30dB) is used to eliminate environmental interference signals, ensuring data validity greater than 95%. The kinetic energy of each droplet is then calculated using a two-dimensional velocity vector. The kinetic energy of all valid droplets is then summed to obtain the total kinetic energy. The volume of each droplet can be calculated based on its particle size, and the volumes of N droplets are summed to obtain the total droplet volume.

[0050] The following specifically describes the process of determining the total volume of droplets when a pressure nozzle is spraying.

[0051] First, when the pressure nozzle is spraying, the particle size of a single droplet collected by the phase Doppler particle analyzer is obtained, and the volume of a single droplet is calculated based on the particle size. The particle size of a single droplet is directly measured by the phase Doppler particle analyzer and is recorded as , i represents the i-th droplet, the volume of a single droplet The calculation formula is as follows:

[0052] (1)

[0053] Furthermore, within the spray width range of the spray, the total number of droplets during the spray is determined based on the number of effective droplets collected at the droplet measurement points. In an embodiment of the present invention, the phase Doppler particle analyzer is disposed within the spray width range of the pressure nozzle spray. This spray width range defines the area of ​​the pressure nozzle spray, and the droplet measurement points are evenly distributed within the spray width range, that is, the horizontal distance between the droplet measurement points is the same, and each droplet measurement point can cover and collect n effective droplets. Thus, in a single sampling cycle of the phase Doppler particle analyzer, effective droplets are evenly collected at each droplet measurement point, and the total number of effective droplets obtained is N. The number of droplet measurement points m is generally 10, and n can be 1000, so N is 10000.

[0054] Finally, the volume of single droplets of the total number of droplets is summed to obtain the total volume of droplets when the pressure nozzle is spraying, which is recorded as Here, the total droplet volume is the sum of the volumes of N single droplets, and the calculation formula is as follows:

[0055] (2)

[0056] In an embodiment of the present invention, a phase Doppler particle analyzer is used to collect effective droplets during spraying of a pressure nozzle, and the number of effective droplets is counted by evenly setting droplet measurement points within the spray width range, thereby reducing the impact of spatial unevenness in the spray area and improving the accuracy of calculating the total droplet volume.

[0057] Next, we will continue to introduce the process of determining the total kinetic energy of droplets when the pressure nozzle is spraying.

[0058] Since droplet collection is performed within the spray width, measurements are performed at uniform and differently positioned droplet measurement points. Therefore, the distance and speed at which each droplet reaches the droplet measurement point after being ejected vary. Because velocity determines the kinetic energy of a droplet, assuming each droplet is identical, the kinetic energy of the droplets collected at different droplet measurement points will vary. Based on this principle, the embodiment of the present invention assigns a corresponding position weight to each droplet measurement point within the spray width, denoted as , j represents the jth droplet measurement point. The position weight of each droplet measurement point is negatively correlated with its actual distance from the pressure nozzle. That is, the closer the actual distance from the droplet measurement point to the pressure nozzle, the greater the assigned position weight, and vice versa. Furthermore, if two droplet measurement points are at the same actual distance from the pressure nozzle, they are assigned the same position weight.

[0059] For example Figure 2 As shown in the figure, the fifth and sixth droplet measurement points are directly below the pressure nozzle and are at the shortest distance from the nozzle. Therefore, these two droplet measurement points are assigned the highest position weight, 0.5. Since the actual distance from the pressure nozzle to the fifth and sixth droplet measurement points is the same, the position weight assigned to them is also the same, 0.5. As the other droplet measurement points on both sides are further away from the pressure nozzle, the position weights assigned to them are gradually reduced, to 0.4, 0.3, 0.2, and 0.1, respectively.

[0060] Next, after the pressure nozzle sprays, the first velocity in the horizontal direction and the second velocity in the vertical direction are determined for each droplet collected at the droplet measurement point. Here, at each droplet measurement point, n valid droplets can be covered and collected. During the collection, the phase Doppler particle analyzer also synchronously collects the two-dimensional velocity vector of the droplet, that is, the first velocity of the droplet in the horizontal direction. and the second velocity in the vertical direction , i represents the i-th droplet.

[0061] Then, at each droplet measurement point, the theoretical spray kinetic energy of each droplet is calculated based on the first velocity and the second velocity. However, when calculating, the first velocity and second speed Calculate the composite speed first ,Right now , and then calculate the theoretical spray kinetic energy, and then calculate the theoretical spray kinetic energy by weighted calculation using the position weight to obtain the actual spray kinetic energy of the droplets, which is recorded as , the formula is as follows:

[0062] (3)

[0063] In the above formula (3), is the droplet size, and They represent the horizontal and vertical speeds of the droplets, respectively. is the density of the droplet liquid, is the position weight of the j-th droplet measurement point, and i represents the i-th droplet collected by the droplet measurement point.

[0064] Finally, the actual spray kinetic energy of each droplet measurement point is summed to obtain the total droplet kinetic energy when the pressure nozzle is spraying. Here, the actual spray kinetic energy of the 10 droplet measurement points is summed, and the obtained total droplet kinetic energy is recorded as , the summation formula is as follows:

[0065] (4)

[0066] In the above formula (4), n represents the total number of droplets collected by the droplet measurement point, i represents the i-th droplet collected by the droplet measurement point, and j represents the j-th droplet measurement point.

[0067] Of course, in actual implementation, the actual spray kinetic energy calculated for each droplet measurement point may have different values. Here, a kinetic energy distribution histogram can be generated based on the total droplet kinetic energy, and the standard deviation and coefficient of variation of the actual spray kinetic energy of m droplet measurement points can be calculated. In order to ensure the validity of the calculation of the actual spray kinetic energy, the RANSA algorithm is used to eliminate outliers (such as eliminating the actual spray kinetic energy of environmental interference particles such as non-droplets), ensuring the validity of the droplet sampling data and the accuracy of the calculation of the total droplet kinetic energy.

[0068] In an embodiment of the present invention, when calculating the kinetic energy of droplets at a droplet measurement point, different position weights are set according to the distance between the droplet measurement point and the pressure nozzle to calculate the kinetic energy. This can effectively eliminate the influence of the spatial resistance encountered by the droplets during the spraying process on the droplet kinetic energy.

[0069] Step 102: Obtain the inlet flow rate of the liquid inside the pressure nozzle pipeline and the nozzle flow rate at the nozzle.

[0070] After calculating the total kinetic energy of the droplets sprayed by the pressure nozzle through the above steps, it is necessary to determine the initial energy inside the nozzle at the pressure nozzle level. This initial energy is affected by the cavity pressure of the pressure nozzle. To calculate the cavity pressure, it is necessary to obtain the inlet flow rate of the liquid inside the pressure nozzle pipe and the nozzle flow rate at the nozzle. Both flow rates can be calculated through the liquid flow rate inside the pressure nozzle and the cross-sectional area of ​​the corresponding nozzle. The details are explained below.

[0071] First, obtain the liquid flow inside the pressure nozzle collected by the electromagnetic flowmeter, such as Figure 2 As shown in the figure, an electromagnetic flowmeter is installed in the pipe of the pressure nozzle, which can collect the liquid flow inside the pressure nozzle in real time, recorded as Q. In addition, the inlet cross-sectional area and nozzle cross-sectional area of ​​the pressure nozzle need to be calculated separately. The pressure nozzle has an inlet for liquid to flow into the pipe and an outlet for spraying. Assuming that the cross-sections of the inlet and outlet are regular circles, the inlet diameter is and outlet diameter All of these can be obtained based on the physical parameters or measurements of the pressure nozzle. The inlet cross-sectional area can be easily calculated based on the diameter. and nozzle cross-sectional area .

[0072] Finally, the inlet and outlet flow rates are calculated based on the liquid flow rate Q and the corresponding cross-sectional area. That is, the ratio of the liquid flow rate to the inlet cross-sectional area is used as the inlet flow rate of the liquid inside the pressure nozzle pipe, which is recorded as The ratio of liquid flow rate to nozzle cross-sectional area is taken as the nozzle velocity of the liquid at the nozzle of the pressure nozzle, which is recorded as , the formula is as follows:

[0073] (5)

[0074] (6)

[0075] In an embodiment of the present invention, the flow rate of the inlet and outlet is calculated by using the real-time collected liquid flow rate and the cross-sectional area of ​​the inlet and outlet to characterize the velocity of the liquid inside the pressure nozzle, laying the foundation for the subsequent calculation of the cavity pressure of the pressure nozzle.

[0076] Step 103: Calculate the cavity pressure of the pressure nozzle according to the inlet flow rate and the nozzle flow rate.

[0077] After calculating the inlet and outlet flow rates of the pressure nozzle in step 102, the modified Bernoulli equation is fitted using the conservation of pressure inside and at the outlet of the nozzle pipe. This process assumes the liquid is incompressible and the flow is steady-state. Because of pressure loss, the Bernoulli equation for pressure conservation needs to be modified, ultimately fitting the modified Bernoulli equation for pressure loss. By solving the modified Bernoulli equation, the cavity pressure of the pressure nozzle is calculated.

[0078] Specifically, it is necessary to first determine the pressure loss of the liquid during the flow in the pressure nozzle pipeline. The pressure loss includes the friction loss determined by the Darcy friction coefficient and the local loss determined by the local loss coefficient. The friction loss and local losses The calculation formulas are as follows:

[0079] (7)

[0080] (8)

[0081] In the above formulas (7) and (8), f is the Darcy friction coefficient, is the local loss coefficient, which can be obtained by consulting the manual, L is the cavity length of the pressure nozzle, Indicates the hydraulic diameter in the pressure nozzle pipe, Indicates the average flow rate of the liquid in the pressure nozzle pipe. is the synthetic velocity obtained by fitting the inlet and outlet flow rates, is the density of the liquid, that is, the density of the droplet liquid.

[0082] The pressure loss during the flow in the pressure nozzle pipeline is the friction loss and local losses The sum of .

[0083] Next, we use the conservation of the internal pressure and outlet pressure of the pressure nozzle pipeline to construct the modified Bernoulli equation. and inlet flow rate , calculate the total inlet pressure of the pressure nozzle. Figure 2 As shown, the pipeline pressure It can be measured in real time using a high-frequency pressure sensor installed in the pressure nozzle pipeline, and the sampling rate of the high-frequency pressure sensor is set to be no less than 1kHz. On the other hand, according to the unknown outlet pressure of the pressure nozzle , nozzle flow rate and pressure loss , determine the total pressure of the nozzle of the pressure nozzle. The outlet pressure of the pressure nozzle is usually atmospheric pressure, that is, the gauge pressure is 0, and the unknown outlet pressure in the embodiment of the present invention is is the cavity pressure of the pressure nozzle to be calculated. Then, based on the total inlet pressure and the total nozzle pressure, the modified Bernoulli equation is constructed as follows:

[0084] (9)

[0085] In the above formula (9), the left side of the equal sign is the total inlet pressure of the pressure nozzle, and the right side of the equal sign is the total nozzle pressure. The equality of the left and right sides represents the conservation of the internal pressure and outlet pressure of the pressure nozzle pipeline, that is, the modified Bernoulli equation is constructed from this.

[0086] Finally, the modified Bernoulli equation is solved and the unknown outlet pressure is obtained. As the cavity pressure of the pressure nozzle, it is recorded as Since the only unknown outlet pressure of the pressure nozzle in the above formula (9) is An unknown number, by solving the above modified Bernoulli equation, we can get:

[0087] (10)

[0088] In an embodiment of the present invention, the Bernoulli equation is fitted using the pressure conservation law of the pressure nozzle, and the Bernoulli equation is corrected under pressure loss. Finally, the modified Bernoulli equation is used to solve the cavity pressure of the pressure nozzle. In this way, the pressure value in the cavity of the pressure nozzle can be accurately calculated, which facilitates the subsequent calculation of the initial energy.

[0089] Step 104 : Calculate the initial energy of the pressure nozzle under the weighted volume based on the cavity pressure, the inlet flow rate, and the total volume of the droplets, and use the ratio of the total kinetic energy of the droplets to the initial energy as the atomization performance index of the pressure nozzle.

[0090] The initial energy of the liquid in the nozzle cavity is generally the initial energy of the liquid in the cavity of the pressure nozzle, that is, the liquid energy before spraying. In an ideal case, this liquid energy includes pressure energy and kinetic energy. The pressure energy can be measured in real time based on the pipeline pressure obtained by the high-frequency pressure sensor. The kinetic energy is calculated by multiplying the liquid flow rate Q by the inlet flow rate. And the liquid flow Q is calculated, that is, However, due to the influence of pressure loss and the fact that only a part of the liquid is sprayed, it is necessary to calculate the initial energy in combination with the total volume of the sprayed liquid. Therefore, in the embodiment of the present invention, the total volume of the droplets is used to calculate the initial energy of the pressure nozzle, that is, the initial energy of the pressure nozzle under the weighted volume.

[0091] The initial energy under the weighted volume still consists of two parts: pressure energy and liquid kinetic energy. The first distribution is based on the inlet flow rate. and the total droplet volume , calculate the inlet kinetic energy of the liquid inside the pressure nozzle, and the second part is based on the cavity pressure and the total droplet volume , calculate the pressure energy of the liquid inside the pressure nozzle, and finally sum the two parts of energy, that is, sum the inlet kinetic energy and the pressure energy to obtain the initial energy of the corresponding weighted volume inside the pressure nozzle, recorded as , expressed as:

[0092] (11)

[0093] In an embodiment of the present invention, the internal pressure energy and inlet kinetic energy of the pressure nozzle are calculated respectively by the total volume of the droplets to accurately characterize the initial energy of the liquid to be sprayed before spraying, thereby facilitating the direct calculation of the atomization performance index of the pressure nozzle and realizing the spray performance evaluation of the pressure nozzle.

[0094] Finally, the ratio of the total kinetic energy of the droplets to the initial energy is used as the atomization performance index of the pressure nozzle. Characterizes the energy of the liquid after spraying, while the initial energy It is the energy inside the pressure nozzle before the liquid is sprayed, so the ratio of the two can be used as an indicator to measure the atomization performance and to evaluate the spray performance and atomization performance of the pressure nozzle. The calculation formula is as follows:

[0095] (12)

[0096] In the above formula (12), represents the particle size of the i-th droplet collected at the j-th droplet measurement point, represents the composite velocity of the i-th droplet collected at the j-th droplet measurement point. The composite velocity is the sum of the horizontal velocity and the square of the vertical velocity. The interpretation of the remaining parameters can refer to the above formulas (3), (4), and (11) and will not be repeated here. By simplifying the above formula (12), we have:

[0097] (13)

[0098] The atomization performance of a pressure nozzle can be used to evaluate the spray performance of the pressure nozzle. The higher the atomization performance, the better the spray performance of the pressure nozzle, and vice versa. Of course, the atomization performance index calculated by the above formula (12) is for tap water spray. According to actual needs, the above method of the embodiment of the present invention can also be used to calculate the atomization performance index of other liquid solutions such as pesticides and plant liquids, or for specific liquids, calculate the atomization performance index of the pressure nozzle under different nozzle types, such as fan nozzles and cone nozzles. In this way, the influence of different liquids or different nozzle types on the atomization performance can be determined, thereby comprehensively evaluating the spray performance of the pressure nozzle.

[0099] In an embodiment of the present invention, the atomization performance index is calculated by calculating the initial energy of the pressure nozzle under the weighted volume and the total kinetic energy of the droplets. As a comprehensive evaluation index for evaluating the pressure nozzle, it can comprehensively reflect the spray performance of the pressure nozzle, provide strong support for the optimal design and selection of the pressure nozzle, and the comprehensive evaluation index can be applied to the spray performance evaluation of different types of pressure nozzles, and has good universality.

[0100] The atomization performance evaluation device for a pressure nozzle provided by the present invention is described below. The atomization performance evaluation device for a pressure nozzle described below and the atomization performance evaluation method for a pressure nozzle described above can be used for reference in correspondence with each other.

[0101] like Figure 3As shown, the atomization performance evaluation device for a pressure nozzle specifically includes: a determination module 301, an acquisition module 302, a calculation module 303, and an evaluation module 304. Specifically, the determination module 301 is used to determine the total volume of droplets and the total kinetic energy of the droplets when the pressure nozzle is spraying; the acquisition module 302 is used to obtain the inlet flow velocity of the liquid inside the pressure nozzle pipeline and the nozzle flow velocity at the nozzle; the calculation module 303 is used to calculate the cavity pressure of the pressure nozzle based on the inlet flow velocity and the nozzle flow velocity; the evaluation module 304 is used to calculate the initial energy of the pressure nozzle under weighted volume based on the cavity pressure, the inlet flow velocity, and the total volume of the droplets, and use the ratio of the total kinetic energy of the droplets to the initial energy as the atomization performance index of the pressure nozzle.

[0102] It should be noted that the beneficial effects of the pressure nozzle atomization performance evaluation device here and the pressure nozzle atomization performance evaluation method mentioned above can correspond to each other, so the beneficial effects of the pressure nozzle atomization performance evaluation device are not repeated here.

[0103] Figure 4 An example of a physical structure diagram of an electronic device is shown below. Figure 4 As shown, the electronic device may include: a processor 410, a communications interface 420, a memory 430, and a communications bus 440, wherein the processor 410, the communications interface 420, and the memory 430 communicate with each other via the communications bus 440. The processor 410 may call logic instructions in the memory 430 to execute a method for evaluating the atomization performance of a pressure nozzle, the method comprising: determining the total volume of droplets and the total kinetic energy of the droplets when the pressure nozzle is spraying; obtaining the inlet flow rate of the liquid inside the pressure nozzle pipe and the nozzle flow rate at the nozzle; calculating the cavity pressure of the pressure nozzle based on the inlet flow rate and the nozzle flow rate; calculating the initial energy of the pressure nozzle under weighted volume based on the cavity pressure, the inlet flow rate, and the total volume of the droplets, and using the ratio of the total kinetic energy of the droplets to the initial energy as an indicator of the atomization performance of the pressure nozzle.

[0104] Furthermore, the logic instructions in the aforementioned memory 430 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product, stored in a storage medium, includes instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0105] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the atomization performance evaluation method of the pressure nozzle provided by the above methods, which includes: determining the total volume of droplets and the total kinetic energy of droplets when the pressure nozzle is spraying; obtaining the inlet flow velocity of the liquid inside the pressure nozzle pipeline and the nozzle flow velocity at the nozzle; calculating the cavity pressure of the pressure nozzle based on the inlet flow velocity and the nozzle flow velocity; calculating the initial energy of the pressure nozzle under weighted volume based on the cavity pressure, the inlet flow velocity and the total volume of droplets, and taking the ratio of the total kinetic energy of the droplets to the initial energy as the atomization performance index of the pressure nozzle.

[0106] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the atomization performance evaluation method of the pressure nozzle provided by the above-mentioned methods, the method comprising: determining the total volume of droplets and the total kinetic energy of droplets when the pressure nozzle is spraying; obtaining the inlet flow velocity of the liquid inside the pressure nozzle pipeline and the nozzle flow velocity at the nozzle; calculating the cavity pressure of the pressure nozzle based on the inlet flow velocity and the nozzle flow velocity; calculating the initial energy of the pressure nozzle under weighted volume based on the cavity pressure, the inlet flow velocity and the total volume of droplets, and taking the ratio of the total kinetic energy of droplets to the initial energy as the atomization performance index of the pressure nozzle.

[0107] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0108] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a necessary general-purpose hardware platform, or of course, hardware. Based on this understanding, the essence of the above technical solution, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, or an optical disk, and includes a number of instructions for causing a computer device (such as a personal computer, server, or network device) to execute the methods described in each embodiment or certain portions of the embodiments.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for evaluating the atomization performance of a pressure nozzle, characterized in that: include: Determine the total volume of droplets and the total kinetic energy of droplets when spraying from a pressure nozzle; Obtaining the inlet flow rate of the liquid inside the pressure nozzle pipe and the nozzle flow rate at the nozzle; Calculating the cavity pressure of the pressure nozzle according to the inlet flow rate and the nozzle flow rate; Calculating the initial energy of the pressure nozzle under weighted volume based on the cavity pressure, the inlet flow rate, and the total volume of the droplets, and using the ratio of the total kinetic energy of the droplets to the initial energy as an atomization performance index of the pressure nozzle; The calculating the initial energy of the pressure nozzle under the weighted volume based on the cavity pressure, the inlet flow rate and the total volume of the droplets includes: Calculating the inlet kinetic energy of the liquid inside the pressure nozzle according to the inlet flow rate and the total volume of the droplets; Calculating the pressure energy of the liquid inside the pressure nozzle according to the cavity pressure and the total volume of the droplets; The inlet kinetic energy and the pressure energy are summed to obtain the initial energy of the corresponding weighted volume inside the pressure nozzle.

2. The method for evaluating the atomization performance of a pressure nozzle according to claim 1, wherein: The process of determining the total volume of droplets when the pressure nozzle is spraying includes: When the pressure nozzle is spraying, the particle size of a single droplet collected by a phase Doppler particle analyzer is obtained, and the volume of the single droplet is calculated based on the particle size; Determine the total number of droplets during spraying based on the number of effective droplets collected at droplet measurement points within the spray width, wherein the droplet measurement points are evenly distributed within the spray width; The volumes of individual droplets of the total number of droplets are summed to obtain the total volume of droplets when the pressure nozzle is spraying.

3. The method for evaluating the atomization performance of a pressure nozzle according to claim 1, wherein: The process of determining the total kinetic energy of droplets when the pressure nozzle is spraying includes: Within the spray width range, a corresponding position weight is assigned to each droplet measurement point, wherein the position weight of each droplet measurement point is negatively correlated with the actual distance from the pressure nozzle; After the pressure nozzle sprays, for each droplet collected at the droplet measurement point, a first velocity in the horizontal direction and a second velocity in the vertical direction are determined respectively; At each droplet measurement point, calculating the theoretical spray kinetic energy of each droplet according to the first velocity and the second velocity, and performing weighted calculation on the theoretical spray kinetic energy using a position weight to obtain the actual spray kinetic energy of the droplet; The actual spray kinetic energy of each droplet measurement point is summed to obtain the total kinetic energy of the droplets when the pressure nozzle is spraying.

4. The method for evaluating the atomization performance of a pressure nozzle according to claim 1, wherein: The method of obtaining the inlet flow rate of the liquid inside the pressure nozzle pipe and the nozzle flow rate at the nozzle comprises: Obtain the liquid flow inside the pressure nozzle collected by the electromagnetic flowmeter; Calculate the inlet cross-sectional area and nozzle cross-sectional area of ​​the pressure nozzle respectively; The ratio of the liquid flow rate to the inlet cross-sectional area is used as the inlet flow rate of the liquid inside the pressure nozzle pipeline, and the ratio of the liquid flow rate to the nozzle cross-sectional area is used as the nozzle flow rate of the liquid at the nozzle of the pressure nozzle.

5. The method for evaluating the atomization performance of a pressure nozzle according to claim 1, wherein: The calculating the cavity pressure of the pressure nozzle according to the inlet flow rate and the nozzle flow rate comprises: Determining the pressure loss of the liquid during the flow in the pressure nozzle pipeline, wherein the pressure loss includes the friction loss determined by the Darcy friction coefficient and the local loss determined by the local loss coefficient; Calculating the total inlet pressure of the pressure nozzle according to the pipeline pressure of the pressure nozzle and the inlet flow rate, and determining the total nozzle pressure of the pressure nozzle according to the unknown outlet pressure of the pressure nozzle, the nozzle flow rate and the pressure loss; Constructing a modified Bernoulli equation based on the inlet total pressure and the nozzle total pressure; The modified Bernoulli equation is solved, and the unknown outlet pressure obtained by the solution is used as the cavity pressure of the pressure nozzle.

6. A device for evaluating the atomization performance of a pressure nozzle, characterized in that: include: A determination module, used to determine the total volume of droplets and the total kinetic energy of droplets when the pressure nozzle is spraying; An acquisition module is used to acquire the inlet flow rate of the liquid inside the pressure nozzle pipeline and the nozzle flow rate at the nozzle; a calculation module, configured to calculate the cavity pressure of the pressure nozzle according to the inlet flow rate and the nozzle flow rate; an evaluation module, configured to calculate the initial energy of the pressure nozzle under weighted volume based on the cavity pressure, the inlet flow rate, and the total volume of the droplets, and use the ratio of the total kinetic energy of the droplets to the initial energy as an atomization performance index of the pressure nozzle; The calculating the initial energy of the pressure nozzle under the weighted volume based on the cavity pressure, the inlet flow rate and the total volume of the droplets includes: Calculating the inlet kinetic energy of the liquid inside the pressure nozzle according to the inlet flow rate and the total volume of the droplets; Calculating the pressure energy of the liquid inside the pressure nozzle according to the cavity pressure and the total volume of the droplets; The inlet kinetic energy and the pressure energy are summed to obtain the initial energy of the corresponding weighted volume inside the pressure nozzle.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the atomization performance evaluation method of the pressure nozzle according to any one of claims 1 to 5 is implemented.

8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the atomization performance evaluation method of the pressure nozzle according to any one of claims 1 to 5 is implemented.

9. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the atomization performance evaluation method of the pressure nozzle according to any one of claims 1 to 5 is implemented.

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