A spraying machine and spraying method based on gas-mist delay coordinated control spraying

Abstract

The present application provides a kind of based on gas-mist delay coordinated control spray spray machine and application method, fan on the application machine selects the axial fan of improvement, the outlet of the side of axial fan far from air inlet is not installed spray head application, simply provides a front airflow, another column outlet installs spray head application, drives the gas, mist flow to reach canopy, when the second airflow of blowing mist carries atomized liquid to reach canopy, first front airflow has first blown the leaf of canopy to a certain amplitude, to form a cross flow, when mist drop deposition adheres, it can directly enter the inside of canopy, so that liquid can be directly sprayed into the inside of canopy, avoid liquid waste accumulation on the surface of canopy, effectively improve the mist drop deposition of the inside of canopy leaf, improve the utilization of pesticide, reduce waste and environmental pollution.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of plant protection machinery, and particularly relates to a spraying machine based on air-mist delayed coordination control spraying and a spraying method. BACKGROUND

[0002] In the technical field of plant protection, the traditional air-assisted spraying method for orchards has a series of problems for fruit trees with large crown diameter and large leaf area density. In the traditional spraying method, the airflow carrying the pesticide solution must disturb the branches and leaves during the contact with the crown layer and deliver the pesticide solution into the crown layer; however, the actual contact time is short, the branches and leaves have not been dispersed, and therefore the atomized pesticide solution is mainly sprayed on the surface of the crown layer, and the mist droplets are difficult to be effectively deposited in the crown layer where the pests and diseases frequently occur, which greatly reduces the spraying effect and causes waste of the pesticide solution. Based on the above problems, the present application adopts an air-mist delayed coordination control spraying method to promote the deposition of the pesticide solution in the crown layer and improve the utilization rate of the pesticide solution. SUMMARY

[0003] In view of the problems in the prior art, the present application provides a spraying machine based on air-mist delayed coordination control spraying and a spraying method, which can prolong the contact time of the crown layer and the airflow, promote the pesticide solution to enter the crown layer, improve the mist droplet deposition on the leaves in the crown layer, reduce the waste of the pesticide solution, and solve the problems in the traditional air-assisted spraying method, such as short contact time of the crown layer and the airflow carrying the pesticide solution, poor effect on fruit trees with large crown diameter and large leaf area density, and mist droplets mainly concentrated on the surface of the crown layer and difficult to be effectively deposited in the crown layer where the pests and diseases frequently occur.

[0004] The present application achieves the above technical purposes through the following technical means.

[0005] A spraying machine based on air-mist delayed coordination control spraying comprises a self-propelled caterpillar chassis, a bearing platform installed on the self-propelled caterpillar chassis, a fixing frame, a pesticide tank, a motor, a binocular camera, a laser radar and an industrial computer installed on the bearing platform; an axial flow fan is installed in the fixing frame, two rows of air outlets are uniformly arranged on the axial flow fan, a nozzle is arranged at the position of one row of air outlets close to the air inlet, the nozzle is connected with a distribution valve through a pesticide pipe, and the distribution valve is communicated with the pesticide tank after passing through a plunger pump.

[0006] Further, adjustable blades and fixed blades are installed in the axial flow fan, the adjustable blades and the fixed blades are staggered and detachably installed on a customized aluminum alloy shaft in front of and behind each other, the fixed blades are located behind the adjustable blades, and a plurality of mounting holes for adjusting the distance between the adjustable blades and the fixed blades are arranged on the aluminum alloy shaft.

[0007] A spraying method using the spraying machine based on air-mist delayed coordination control spraying comprises the following processes:

[0008] S1: preliminary test, determine the fan selection;

[0009] S2: determine the first stage pre-flow outlet air speed u1;

[0010] S3: determine the second stage blowing mist airflow outlet air speed u2;

[0011] S4: after determining the set value u1, u2, start the axial flow fan, use the fan speed regulator to adjust the air speed, after the axial flow fan runs for a period of time, measure the first stage pre-flow outlet air speed with the air speed meter, adjust the fan speed regulator knob rotation amount according to the measured value, so that the air speed reaches the set value u1, disturb the canopy branches and leaves, and continue to adjust the second stage blowing mist airflow outlet air speed to reach the set value u2;

[0012] S5: turn on the plunger pump switch, when the mist droplets sprayed by the nozzle are uniform and do not change with time, under the comprehensive control of the industrial computer, the self-propelled tracked chassis drives the sprayer to move and starts to spray according to the set outlet air speed.

[0013] Further, the specific process of S1 is as follows:

[0014] Under the comprehensive control of the industrial computer, the self-propelled tracked chassis drives the sprayer to walk at the set walking speed, while controlling the plunger pump and distribution valve to work, and the sprayer sprays according to the set spraying flow rate. In this process, the industrial computer calculates the fan air volume Q according to the working parameters, Q≥(R+h)·L'FK, K is the gas loss coefficient, h is half the distance between the two rows of air outlets; R is the fan inlet air port radius, L' is the vertical distance from the inlet air port to the bottom air outlet; F is the working speed;

[0015] The industrial computer calculates the fan air pressure P according to the following formula:

[0016]

[0017] Where, ρ is the air mass density; v is the air flow speed in the air duct; λ is the friction factor; R is the air pipe radius; ξ is the local resistance coefficient; l is the air duct straight pipe length;

[0018] Then, based on the calculated air volume Q and air pressure P, the fan power N is calculated:

[0019]

[0020] Where, η j is the impeller efficiency, η m is the mechanical efficiency;

[0021] The data obtained by comprehensive calculation determines that the final selection of the fan is an axial fan with a diameter of 150 mm and a maximum rotating speed of 5000 r / min. The axial fan is installed at a height of 1.1 m from the ground and provides a first-stage pre-flow at the air outlet near the air inlet side to realize the early disturbance of the crown branches and leaves. The air outlet at the other side provides a second-stage blowing mist flow to carry the mist droplets to the crown for pesticide application.

[0022] Further, the specific process of S2 is as follows:

[0023] The disturbance effect of the first-stage pre-flow on the crown branches and leaves will continuously lose momentum under the influence of air resistance, and the momentum loss formula is as follows:

[0024]

[0025] wherein, represents the momentum loss of the first-stage pre-flow; μ is the viscosity coefficient of the airflow; u1 is the outlet wind speed of the first-stage pre-flow; D is the viscous resistance coefficient; C is the inertial resistance coefficient, which can be determined by the crown porosity value; and ρ is the air density;

[0026] Under the influence of the crown branches and leaves and air viscous resistance, the kinetic energy of the first-stage pre-flow continuously decays and dissipates, and finally penetrates the crown with a certain airflow terminal speed u′1. The outlet wind speed u1 of the first-stage pre-flow is finally determined by the steady flow momentum formula as follows:

[0027]

[0028] Q m = ρ·u1·S

[0029] wherein, Q m is the gas mass flow rate; u′1 is the speed of the first-stage pre-flow reaching the tree trunk; and S is the cross-sectional area of the air outlet.

[0030] Further, the specific process of S3 is as follows:

[0031] The outlet wind speed u2 of the second-stage blowing mist flow is calculated according to the terminal speed principle formula and the axial velocity formula of the gas free submerged jet motion relationship as follows:

[0032]

[0033]

[0034] wherein, u′2 is the terminal speed of the second-stage blowing mist flow reaching the tree; u2 is the outlet wind speed of the second-stage blowing mist flow; h is the tree height; and A is the turbulence coefficient.

[0035] The present invention has the following beneficial effects:

[0036] This invention differs from traditional pesticide application methods by dividing wind-assisted application into two stages. The first stage is a single airflow used to disturb the canopy foliage, allowing droplets to deposit more effectively on the leaves while ensuring sufficient dispersion of the canopy foliage in the second stage, enabling more pesticide to be sprayed into the inner canopy. The second stage is a mixed air-mist flow carrying the pesticide, with a certain time difference from the first stage. After the single airflow disperses the canopy foliage, it carries the pesticide and delivers it to the inner canopy, while simultaneously disturbing the inner foliage to increase droplet deposition. Therefore, this invention, through this air-mist delayed coordinated spraying method, effectively improves droplet deposition on the inner canopy leaves, increases pesticide utilization, and reduces waste and environmental pollution. Attached Figure Description

[0037] Fig. 1 This is a schematic diagram of the overall structure of the spraying machine described in this invention;

[0038] Fig. 2 This is a side view of the spraying machine described in this invention;

[0039] Fig. 3 This is a front view of the spraying machine described in this invention;

[0040] Fig. 4 This is a schematic diagram of the air inlet and outlet of the axial flow fan described in this invention.

[0041] In the diagram: 1-Adjustable fan blade; 2-Fixed fan blade; 3-Nozzle; 4-Fixed frame; 5-Medicine tank; 6-Motor; 7-Binocular camera; 8-LiDAR; 9-Industrial computer; 10-Load-bearing platform; 11-Self-propelled tracked chassis; 12-Plunger pump; 13-Distribution valve; 14-Medicine pipe; 15-Axial flow fan. Detailed Implementation

[0042] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto. The present invention uses the grape canopy as the research object for the description of the scheme. For the grape canopy, regarding the outlet wind speed, when the outlet wind speed of the first-stage pre-airflow is approximately 15 m / s and the outlet wind speed of the second-stage misting airflow is approximately 10 m / s, the canopy liquid coverage is most uniform. Regarding the blade spacing, the most uniform overall canopy coverage occurs when the distance between the two blades is between 10 and 16 cm. As for the influence of the density of the leaves, different wind speeds and blade spacings need to be determined according to the actual situation in application.

[0043] like Figs. 1 to 3As shown, the spraying machine based on air-mist delay coordinated control spraying of the present invention includes a self-propelled tracked chassis 11, a carrying platform 10, an axial flow fan 15, a medicine tank 5, a nozzle 3, a fixing frame 4, a motor 6, a binocular camera 7, a lidar 8, an industrial control computer 9, a plunger pump 12, and a distribution valve 13.

[0044] like Figs. 1 to 3 As shown, the self-propelled tracked chassis 11 is driven by a diesel engine. During operation, the speed and direction can be adjusted as needed. A carrying platform 10 is mounted on the self-propelled tracked chassis 11. The carrying platform 10 is equipped with a fixed frame 4, a medicine tank 5, a motor 6, a binocular camera 7, a lidar 8, and an industrial control computer 9. The fixed frame 4 is located at one end of the carrying platform 10 and is square. The fixed frame 4 is perpendicular to the carrying platform 10, and an axial flow fan 15 is installed in the fixed frame 4. The axial flow fan 15 has two rows of air outlets, with each air outlet in each row spaced 10cm apart. The air outlet on the side furthest from the air inlet does not have a nozzle 3 installed, and simply provides a pre-flow. The air outlet on the side closer to the air inlet has a nozzle 3 installed. The nozzle 3 is connected to the distribution valve 13 through the medicine pipe 14. The distribution valve 13 is connected to the medicine tank 5 on the support platform 10 behind the axial flow fan 15 after passing through the plunger pump 12. Under the comprehensive control of the industrial control computer 9, the medicine in the medicine tank 5 can be sprayed out through the nozzle 3, and spray application can be achieved under the action of the axial flow fan 15.

[0045] like Figs. 1 to 4 As shown, the axial flow fan 15 is equipped with adjustable fan blades 1 and fixed fan blades 2. The adjustable fan blades 1 and fixed fan blades 2 are of the same model, both being duct fan blades with stepless speed regulation. They are controlled by DC inverter motor technology, with a blade diameter of 150mm and a maximum speed of 5000r / min. An anemometer shows that the maximum outlet wind speed of the axial flow fan 15 is 15m / s, and the adjustable outlet wind speed range is 0-15m / s. The adjustable fan blades 1 and fixed fan blades 2 are staggered on a custom-made aluminum alloy shaft, with the fixed fan blades 2 located behind the adjustable fan blades 1. The aluminum alloy shaft has multiple mounting holes for easy adjustment of the distance between the adjustable fan blades 1 and the fixed fan blades 2. In this embodiment, the distance between the adjustable fan blades 1 and the fixed fan blades 2 is maintained within the range of 4-22cm.

[0046] The motor 6, binocular camera 7, and lidar 8 are all connected to the industrial control computer 9. The binocular camera 7 and lidar 8 transmit monitoring data to the industrial control computer 9 for analysis and processing to achieve path navigation. The motor 6 is used to control the operation of the nozzle 3.

[0047] The application method using the above-mentioned sprayer based on air-mist delay coordination control includes the following steps:

[0048] S1: Preliminary testing, fan selection:

[0049] Under the comprehensive control of the industrial control computer 9, the self-propelled tracked chassis 11 drives the sprayer to travel at the set walking speed, while simultaneously controlling the operation of the plunger pump 12, the distribution valve 13, etc. The sprayer performs the spraying operation according to the set spraying flow rate. During this process, the industrial control computer 9 calculates the fan air volume Q according to the working parameters, Q≥(R+h)·L'FK, where K is the gas loss coefficient, generally taken as 1.3~1.6, h is half the distance between the two rows of air outlets, R is the radius of the fan inlet, L' is the vertical distance from the inlet to the bottom outlet, and F is the operating speed.

[0050] The industrial control computer 9 then calculates the fan pressure P according to the following formula:

[0051]

[0052] Where ρ is the airflow mass density, in kg / m³. 3 v is the airflow velocity in the duct, in m / s; λ is the friction coefficient; R is the duct radius, in m; ξ is the local resistance coefficient; l is the length of the straight duct, in m.

[0053] Then, based on the air volume Q and air pressure P calculated above, the fan power N is calculated:

[0054]

[0055] Where, η j For impeller efficiency, take 0.98, η m For mechanical efficiency, take 0.9;

[0056] Based on the comprehensive calculations, the final selection of the fan was determined to be an axial flow fan 15 with a diameter of 150mm and a maximum speed of 5000r / min. An anemometer reading showed a maximum outlet air velocity of 15m / s. The axial flow fan 15 was installed at a height of 1.1m above the ground. Fig. 4 As shown, two rows of air outlets are evenly spaced 10cm apart on the axial flow fan 15. The air outlet on the side closer to the air inlet provides the first stage of pre-airflow to achieve early disturbance of the canopy branches and leaves, while the air outlet on the other side provides the second stage of misting airflow to carry the mist droplets to the canopy for pesticide application.

[0057] S2: Determine the outlet wind speed u1 of the first-stage forward airflow:

[0058] For the preceding airflow in the first stage, its disturbance effect on the canopy branches and leaves will cause its momentum to continuously decrease due to air resistance. The momentum loss formula is as follows:

[0059]

[0060] in, The first-stage forward airflow represents the momentum loss, expressed in Pa; μ is the airflow viscosity coefficient, expressed in Pa·s. -1 u1 represents the outlet velocity of the first-stage pre-flow, in milliseconds (ms). -1 D is the viscous drag coefficient; C is the inertial drag coefficient, which can be determined by the canopy permeability; ρ is the air density, in kg·m³. -1 ;

[0061] Under the obstruction of canopy branches and leaves and the viscous drag of air, the kinetic energy of the first-stage leading airflow continuously decays and dissipates, eventually passing through the canopy at a certain terminal velocity u′1. The exit velocity u1 of the first-stage leading airflow is finally determined by the steady flow momentum formula shown below:

[0062]

[0063] Q m =ρ·u1·S

[0064] Among them, Q m U is the gas mass flow rate, in kg / s; u′1 is the velocity of the first-stage precursor gas flow reaching the tree trunk, in m / s. -1 Preliminary experiments show that u′1 = 1.0~2.0 m / s; S is the cross-sectional area of ​​the air outlet, in m². 2 The final calculation yields u1≈10~20m / s, and we take 15m / s.

[0065] S3: Determine the outlet wind speed u2 of the second-stage mist blowing airflow.

[0066] The outlet wind speed u2 of the second-stage mist blowing airflow is calculated based on the following formulas: the final velocity principle formula and the axial velocity formula of the gas free submersion jet motion relationship (since the air supply distance has little to no effect on the amount of mist droplets deposited, its influence is not considered):

[0067]

[0068]

[0069] Where u′2 is the final velocity of the second-stage misting airflow reaching the tree; u2 is the outlet wind speed of the second-stage misting airflow; h is the tree height; A is the turbulence coefficient. The final calculated airflow of u2≈10m / s meets the optimal airflow to reach the target of the pesticide application.

[0070] S4: After determining the set values ​​u1 and u2, start the axial flow fan 15 and use the fan speed controller to adjust the wind speed. After the axial flow fan 15 has been running for a period of time, use an anemometer to measure the outlet wind speed of the first stage pre-flow. Adjust the rotation of the fan speed controller knob according to the measured value so that the wind speed reaches the set value u1, disturbing the canopy branches and leaves. Continue to adjust the outlet wind speed of the second stage mist blowing airflow to reach the set value u2.

[0071] S5: Turn on the plunger pump 12 switch. When the droplets sprayed from the nozzle 3 are evenly sprayed and do not change over time, under the comprehensive control of the industrial control computer 9, the self-propelled tracked chassis 11 drives the sprayer to move and begins to spray pesticides according to the set outlet wind speed.

[0072] The self-propelled tracked chassis power module 2 and support platform module adopt conventional structural settings, and therefore will not be described in detail in this application. The embodiments described are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essence of the present invention are within the protection scope of the present invention.

Claims

1. A spraying method using a sprayer based on air-mist delay coordination control, characterized in that, The spraying machine includes a self-propelled tracked chassis (11), a carrying platform (10) is mounted on the self-propelled tracked chassis (11), and a fixed frame (4), a medicine tank (5), a motor (6), a binocular camera (7), a lidar (8), and an industrial control computer (9) are mounted on the carrying platform (10); an axial flow fan (15) is installed in the fixed frame (4), and two rows of air inlets are evenly opened on the axial flow fan (15). A nozzle (3) is provided at the position of one row of air inlets near the air inlet, and the nozzle (3) passes through... The medicine pipe (14) is connected to the distribution valve (13), and the distribution valve (13) is connected to the medicine tank (5) after passing through the plunger pump (12); the axial flow fan (15) is equipped with an adjustable fan blade (1) and a fixed fan blade (2). The adjustable fan blade (1) and the fixed fan blade (2) are detachably installed on a custom aluminum alloy shaft, one in front of the other, and the fixed fan blade (2) is located behind the adjustable fan blade (1). The aluminum alloy shaft is provided with multiple mounting holes to facilitate the adjustment of the distance between the adjustable fan blade (1) and the fixed fan blade (2); The spray application method includes the following steps: S1: Preliminary testing to determine the fan selection; S2: Determine the outlet wind speed u1 of the first-stage pre-flow; S3: Determine the outlet wind speed u2 of the second-stage mist blowing airflow; S4: After determining the set values ​​u1 and u2, start the axial flow fan (15) and use the fan speed controller to adjust the wind speed. After the axial flow fan (15) has been running for a period of time, use an anemometer to measure the outlet wind speed of the first stage pre-flow. Adjust the fan speed controller knob rotation according to the measured value so that the wind speed reaches the set value u1, disturb the canopy branches and leaves, and continue to adjust the outlet wind speed of the second stage mist blowing airflow to reach the set value u2. S5: Turn on the plunger pump (12) switch. When the droplets sprayed by the nozzle (3) are evenly sprayed and do not change with time, under the comprehensive control of the industrial control computer (9), the self-propelled tracked chassis (11) drives the sprayer to move and starts spraying medicine according to the set outlet wind speed.

2. The spray application method according to claim 1, characterized in that, The specific process of S1 is as follows: Under the comprehensive control of the industrial control computer (9), the self-propelled tracked chassis (11) drives the sprayer to walk at the set walking speed, and at the same time controls the plunger pump (12) and the distribution valve (13) to work. The sprayer performs the spraying operation according to the set spraying flow rate. During this process, the industrial control computer (9) calculates the fan air volume Q according to the working parameters, Q≥(R+h)·L'FK, where K is the gas loss coefficient, h is half the distance between the two air outlets, R is the radius of the fan inlet, L' is the vertical distance from the inlet to the bottom outlet, and F is the working speed. The industrial control computer (9) then calculates the fan pressure P according to the following formula: Where ρ is the airflow mass density; v is the airflow velocity in the duct; λ is the friction coefficient; ξ is the local drag coefficient; and l is the length of the straight duct. Then, based on the air volume Q and air pressure P calculated above, the fan power N is calculated: Where, η j For impeller efficiency, η m For mechanical efficiency; Based on the comprehensive calculation data, the final selection of the fan was determined to be an axial flow fan (15) with a diameter of 150mm and a maximum speed of 5000r / min. The axial flow fan (15) was installed at a height of 1.1m above the ground. The air outlet on the side near the air inlet provided the first stage of pre-airflow to achieve early disturbance of the canopy branches and leaves. The air outlet on the other side provided the second stage of blowing airflow to carry the mist droplets to the canopy for pesticide application.

3. The spray application method according to claim 1, characterized in that, The specific process of S2 is as follows: The disturbance effect of the leading airflow on the canopy branches and leaves in the first stage will cause the momentum to be continuously lost and decayed under the influence of air resistance. The momentum loss formula is as follows: in, The first stage of the preceding airflow represents the momentum loss; μ is the airflow viscosity coefficient; D is the viscous drag coefficient; C is the inertial drag coefficient, which can be determined by the canopy permeability value; ρ is the air density. Under the obstruction of canopy branches and leaves and the viscous drag of air, the kinetic energy of the first-stage leading airflow continuously decays and dissipates, eventually passing through the canopy at a certain terminal velocity u1'. The exit velocity u1 of the first-stage leading airflow is finally determined by the steady flow momentum formula shown below: Q m =ρ·u1·S Among them, Q m U is the gas mass flow rate; u1' is the velocity of the first-stage pre-flow reaching the tree trunk; S is the cross-sectional area of ​​the air outlet.

4. The spray application method according to claim 1, characterized in that, The specific process of S3 is as follows: The outlet wind speed u2 of the second-stage blowing mist airflow is calculated based on the following formulas: the final velocity principle formula and the relationship between the free submerged jet motion and the axial velocity formula. Where u2' is the final velocity of the second-stage mist airflow reaching the tree; h' is the tree height; A is the turbulence coefficient; R represents the radius of the fan inlet; S represents the cross-sectional area of ​​the outlet; K represents the gas loss coefficient; and l represents the length of the straight duct.

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