A stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter

Abstract

The present invention belongs to the technical field of agricultural water-saving irrigation drip irrigation equipment. A stepped energy dissipation and active compensation suitable low-pressure drip irrigation emitter includes a flow-through inner cavity and a flow-through outer cavity. The flow-through inner cavity and the flow-through outer cavity are respectively arranged on the inner side and the outer side of the capillary tube. A toothed labyrinth flow channel is fixedly arranged on the inner wall of the flow-through inner cavity. Inner cavity water outlet holes are arranged on the tube wall of the capillary tube. The flow-through inner cavity and the flow-through outer cavity are communicated through the inner cavity water outlet holes. The flow-through outer cavity includes an upper annular semi-circular sleeve and a lower annular semi-circular sleeve, and the upper annular semi-circular sleeve and the lower annular semi-circular sleeve are closely attached to the outer wall of the capillary tube in a nested manner. The emitter can achieve uniform outflow under different working head conditions under a low-pressure working condition of less than 5 m. At the same time, the anti-clogging performance of the emitter can be improved by increasing the flow channel size, so as to keep the stable outflow performance of the emitter.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural water-saving irrigation drip irrigation equipment, and particularly to a stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter. Background Technique

[0002] Drip irrigation technology can achieve efficient water conservation and increase crop yield and quality, and is widely used worldwide. In recent years, with the large-scale popularization of drip irrigation technology, China has become the country with the largest application area of drip irrigation technology in the world. The problem of high energy consumption in drip irrigation systems has attracted wide attention, and the low-pressure operation of drip irrigation systems has become a hot research direction in drip irrigation technology. On the one hand, low-pressure drip irrigation can significantly reduce system energy consumption and uniformity costs, and reduce the emissions of irrigation greenhouse gases. On the other hand, low-pressure drip irrigation systems can use pipes with smaller wall thicknesses and pumps with smaller powers, etc., significantly reducing the project cost.

[0003] The existing patent CN105706854A discloses an anti-clogging emitter based on the cross-section double-circulation phenomenon of a bend. To optimize the flow channel structure, avoid sharp corners and corners in the flow channel, and eliminate the flow stagnation area in the flow channel. However, a large number of practical results show that it is still difficult to effectively solve the problem of easy clogging of the emitter under low-pressure conditions only through the optimized design of the flow channel structure. Another effective measure to enhance the anti-clogging performance of the emitter is to increase the flow channel size. However, increasing the flow channel size on an inlaid patch or inlaid cylinder with limited size will reduce the energy dissipation effect of the emitter and significantly change the outflow characteristics of the emitter. Therefore, the main problem in the current drip irrigation emitter technology lies in the drip irrigation emitter. Summary of the Invention

[0004] The purpose of the present invention is to provide a stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter, which can achieve uniform outflow under different working head conditions under low-pressure conditions below 5m, and at the same time can improve the anti-clogging performance of the emitter by increasing the flow channel size, so as to keep the stable outflow performance of the emitter.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter, including a flow-through inner cavity and a flow-through outer cavity, the flow-through inner cavity and the flow-through outer cavity are respectively arranged inside and outside the capillary;

[0007] Strip-shaped patches are fixedly arranged on the inner wall of the flow-through inner cavity, inner cavity water outlet holes are provided on the wall of the capillary, the inner cavity water outlet holes adopt a circular structure with an inner diameter of 1.6 mm, and the flow-through inner cavity is communicated with the flow-through outer cavity through the inner cavity water outlet holes;

[0008] The overcurrent outer cavity includes an upper annular semi-circular sleeve and a lower annular semi-circular sleeve, and the upper annular semi-circular sleeve and the lower annular semi-circular sleeve are closely attached to the outer wall of the capillary by means of mutual nesting. After the flow-stabilizing grooves of the lower annular semi-circular sleeve and the upper annular semi-circular sleeve are closed, a closed water storage cavity is formed, and after the water collecting grooves of the lower annular semi-circular sleeve and the upper annular semi-circular sleeve are closed, a closed water collecting cavity is formed.

[0009] Further preferably, the toothed maze flow channels in the strip-shaped patch are composed of multiple toothed maze flow channel units, and the toothed maze flow channels are arranged in two rows at equal intervals in parallel. The size of the strip-shaped patch is 31 mm in length, 9 mm in width, and 4 mm in height. The width of the toothed maze flow channel unit is 1 mm, the depth is 1.1 mm, the included angle is 60°, the tooth tip difference is 0.2 mm, and the tooth height is 1.6 mm.

[0010] Further preferably, one end of the upward toothed maze flow channel is connected with a grid-shaped water inlet, the size of the grid-shaped water inlet is 10.4 mm in length and 3 mm in width. The other end of the upward toothed maze flow channel is connected with the downward toothed maze flow channel through a smooth arc chamfer. The other end of the downward toothed maze flow channel is connected with a patch water outlet groove, the patch water outlet groove is a rectangle with a size of 8 mm in length and 7 mm in width, and the patch water outlet groove is connected with the flow-stabilizing groove through an inner cavity water outlet hole.

[0011] Further preferably, stop platforms are provided at both ends of the upper annular semi-circular sleeve. A toothed maze flow channel section is arranged in the middle of the upper annular semi-circular sleeve. The angle of 12 teeth of the toothed maze flow channel section is 60°, the flow channel width is 0.9 mm, the tooth pitch is 2.3 mm, the tooth bottom distance is 0.70 mm, the tooth width is 1.62 mm, the flow channel depth is 0.9 mm, and the tooth tip difference is 0.2 mm. One side of the toothed maze flow channel section is a flow-stabilizing groove, the width of the flow-stabilizing groove is 20 mm, and the depth of the flow-stabilizing groove recessed from the inner wall of the sleeve is 1.5 mm. The other side of the toothed maze flow channel section is a water collecting groove, the width of the water collecting groove is 20 mm, the depth of the water collecting groove recessed from the inside of the sleeve is 1.5 mm. The distance between the flow-stabilizing groove and the water collecting groove from the end of the sleeve is 5 mm. A plurality of first outer cavity water outlet holes are evenly distributed on the stop platform close to the water collecting groove.

[0012] Further preferably, symmetric convex wings and grooves are respectively arranged at the centers of the two long sides of the upper annular semi-circular sleeve and the lower annular semi-circular sleeve. The convex wings are trapezoidally designed, with the top side length of 15 mm, the bottom side length of 16 mm, and the height of 5 mm. The grooves are rectangularly designed, with the width of 15 mm and the depth of 5 mm.

[0013] Further preferably, stop platforms are provided at both ends of the lower annular semi-circular sleeve. A flow stabilizing groove and a water collecting groove are arranged inside the lower annular semi-circular sleeve. A plurality of second outer cavity water outlet holes are evenly distributed on the stop platform close to the water collecting groove, and the second outer cavity water outlet holes are arranged in a semi-circular shape. The dimensions of the flow stabilizing groove, water collecting groove, stop platform, and second outer cavity water outlet holes of the lower annular semi-circular sleeve are the same as those of the flow stabilizing groove, water collecting groove, stop platform, and first outer cavity water outlet holes of the upper annular semi-circular sleeve.

[0014] The convex wing of the upper annular semi-circular sleeve is combined with the groove of the lower annular semi-circular sleeve, and the groove of the upper annular semi-circular sleeve is combined with the convex wing of the lower annular semi-circular sleeve to form a flow-through outer cavity by splicing. Since the width of the convex groove is slightly larger than the width of the groove, the friction force can be increased by extrusion deformation to achieve a firm connection between the upper annular semi-circular sleeve and the lower annular semi-circular sleeve.

[0015] Further preferably, it further includes a branch pipe. A plurality of capillary pipes are connected to the outside of the branch pipe. A valve is arranged at the connection of each capillary pipe and the branch pipe. On the side of the valve away from the branch pipe, a capillary pipe initial stage water emitter, a capillary pipe middle stage water emitter, and a capillary pipe end stage water emitter are arranged in sequence from near to far. The capillary pipe initial stage water emitter, the capillary pipe middle stage water emitter, and the capillary pipe end stage water emitter respectively correspond to the capillary pipe first stage energy dissipation outer cavity, the capillary pipe middle stage energy dissipation outer cavity, and the capillary pipe end stage energy dissipation outer cavity, and the number of teeth in the tooth-shaped maze flow channel section is 20 teeth, 16 teeth, and 12 teeth respectively.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] 1. A stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter provided by the present invention combines stepped energy dissipation through the tooth-shaped maze flow channel in the flow-through inner cavity and the tooth-shaped maze flow channel in the flow-through outer cavity. Due to the increase in the total length of the flow channel, the flow channel size of the emitter, especially the width of the inner cavity tooth-shaped maze flow channel, can be increased to more than 1 mm, significantly improving the anti-clogging performance of the emitter.

[0018] 2. A stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter provided by the present invention has the flow-through outer cavity connected to the flow-through inner cavity through upper and lower annular semi-circular sleeves. The upper and lower annular semi-circular sleeves are connected by embedding through convex wings and grooves, which is convenient for disassembly and assembly. When it is found that the emitter is clogged during operation, the inner and outer cavities can be easily disassembled and flushed, effectively solving the problem that it is difficult to eliminate or relieve clogging after the traditional drip irrigation emitter is clogged.

[0019] 3. A grading energy dissipation active compensation suitable low-pressure drip irrigation emitter provided by the present invention, the toothed maze flow channel of the over-flow outer cavity adopts a variable tooth number differential energy dissipation design. The farther the distance from the head end of the capillary, the fewer the tooth numbers of the toothed maze flow channel section in the over-flow outer cavity, and the lower the energy dissipation of the toothed maze flow channel, effectively offsetting the energy loss in the capillary caused by the frictional resistance along the way or locally, so that the outflow rates of each section along the capillary tend to be uniform.

[0020] 4. A grading energy dissipation active compensation suitable low-pressure drip irrigation emitter provided by the present invention actively compensates the pressure through the difference in the energy dissipation effect of the emitter. The structure of the emitter is simple, without the need to adopt an elastic diaphragm with high requirements for material performance, and can achieve the compensation of pressure and flow rate under low working head. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is the overall assembly structure diagram of the emitter of the present invention;

[0022] Figure 2 It is the schematic structural diagram of the inner cavity of the emitter of the present invention;

[0023] Figure 3 It is the schematic structural diagram of the capillary of the emitter of the present invention;

[0024] Figure 4 It is the schematic structural diagram of the strip patch with a toothed maze flow channel of the emitter of the present invention;

[0025] Figure 5 It is the schematic structural diagram of the upper annular semi-circular sleeve of the emitter of the present invention;

[0026] Figure 6 It is the schematic structural diagram of the lower annular semi-circular sleeve of the emitter of the present invention;

[0027] Figure 7 It is the schematic structural diagram of the emitter at the initial stage of the capillary with differential energy dissipation design of the present invention;

[0028] Figure 8 It is the schematic structural diagram of the emitter in the middle section of the capillary with differential energy dissipation design of the present invention;

[0029] Figure 9 It is the schematic structural diagram of the emitter at the end stage of the capillary with differential energy dissipation design of the present invention;

[0030] Figure 10 It is the schematic diagram of the capillary for grading and assembling the emitter of the present invention;

[0031] Figure 11 It is the hydraulic performance diagram of the emitter of the present invention under low-pressure conditions;

[0032] Figure 12 It is the simulation result diagram of the pressure change of the grading pressure compensation flow channel in the outer cavity of the emitter;

[0033] Figure 13 Schematic diagram of the performance of the device under different water heads

[0034] Figure 14 Schematic diagram of the outflow performance of the long capillary tube with the water emitter of the present invention assembled thereon;

[0035] Figure 15 Cross-sectional view of the water emitter of the present invention assembled;

[0036] In the figure: 1, flow-through inner cavity; 2, flow-through outer cavity; 3, capillary tube; 4, strip-shaped patch; 5, inner cavity water outlet hole; 6, grid-shaped water inlet; 7, toothed maze flow channel unit; 8, patch water outlet groove; 9, upper annular semi-circular sleeve; 10, water stop platform; 11, flow stabilization groove; 12, toothed maze flow channel section; 13, water collection tank; 14, first outer cavity water outlet hole; 15, convex wing; 16, groove; 17, lower annular semi-circular sleeve; 18, second outer cavity water outlet hole; 19, energy dissipation outer cavity at the head section of the capillary tube; 20, energy dissipation outer cavity at the middle section of the capillary tube; 21, energy dissipation outer cavity at the end section of the capillary tube; 22, branch pipe; 23, valve; 24, water emitter at the initial section of the capillary tube; 25, water emitter at the middle section of the capillary tube; 26, water emitter at the end section of the capillary tube. Detailed implementation manners

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0038] Please refer to Figures 1-15 , the present invention provides a technical solution:

[0039] A stepped energy dissipation and active compensation suitable low-pressure drip irrigation water emitter, comprising a flow-through inner cavity 1 and a flow-through outer cavity 2, the flow-through inner cavity 1 and the flow-through outer cavity 2 are respectively arranged inside and outside the capillary tube 3;

[0040] A strip-shaped patch 4 is fixedly arranged on the inner wall of the flow-through inner cavity 1, an inner cavity water outlet hole 5 is provided on the tube wall of the capillary tube 3, the inner cavity water outlet hole 5 adopts a circular structure with an inner diameter of 1.6 mm, and the flow-through inner cavity 1 and the flow-through outer cavity 2 are communicated through the inner cavity water outlet hole 5;

[0041] The overcurrent outer cavity 2 includes an upper annular semi-circular sleeve 9 and a lower annular semi-circular sleeve 17, and the upper annular semi-circular sleeve 9 and the lower annular semi-circular sleeve 17 are closely attached to the outer wall of the capillary tube 3 in a nested manner. After the steady flow grooves 11 of the lower annular semi-circular sleeve 17 and the upper annular semi-circular sleeve 9 are closed, a closed water storage cavity is formed. After the water collecting grooves 13 of the lower annular semi-circular sleeve 17 and the upper annular semi-circular sleeve 9 are closed, a closed water collecting cavity is formed.

[0042] In the present invention, the tooth-shaped maze flow channel in the strip-shaped patch 4 is composed of a plurality of tooth-shaped maze flow channel units 7, and the tooth-shaped maze flow channels are arranged in two rows at equal intervals in parallel. The size of the strip-shaped patch 4 is 31 mm in length, 9 mm in width, and 4 mm in height. The width of the tooth-shaped maze flow channel unit 7 is 1 mm, the depth is 1.1 mm, the included angle is 60°, the tooth tip difference is 0.2 mm, and the tooth height is 1.6 mm.

[0043] In the present invention, one end of the upward tooth-shaped maze flow channel is connected to a grid-shaped water inlet 6. The size of the grid-shaped water inlet 6 is 10.4 mm in length and 3 mm in width. The other end of the upward tooth-shaped maze flow channel is connected to the downward tooth-shaped maze flow channel through a smooth arc chamfer. The other end of the downward tooth-shaped maze flow channel is connected to a patch water outlet groove 8. The patch water outlet groove 8 is a rectangle with a length of 8 mm and a width of 7 mm. The patch water outlet groove 8 is connected to the steady flow groove 11 through an inner cavity water outlet hole 5.

[0044] In the present invention, stop platforms 10 are provided at both ends of the upper annular semi-circular sleeve 9. A tooth-shaped maze flow channel section 12 is arranged in the middle section of the upper annular semi-circular sleeve 9. The tooth angle of the tooth-shaped maze flow channel section 12 is 60°, the flow channel width is 0.9 mm, the tooth pitch is 2.3 mm, the tooth bottom distance is 0.70 mm, the tooth width is 1.62 mm, the flow channel depth is 0.9 mm, and the tooth tip difference is 0.2 mm. One side of the tooth-shaped maze flow channel section 12 is a steady flow groove 11 with a width of 20 mm, and the depth of the steady flow groove 11 recessed from the inner wall of the sleeve is 1.5 mm. The other side of the tooth-shaped maze flow channel section 12 is a water collecting groove 13 with a width of 20 mm, and the depth of the water collecting groove 13 recessed from the inside of the sleeve is 1.5 mm. The distance between the steady flow groove 11 and the water collecting groove 13 from the end of the sleeve is 5 mm. A plurality of first outer cavity water outlet holes 14 are evenly distributed on the stop platform 10 close to the water collecting groove 13.

[0045] In the present invention, symmetric convex wings 15 and grooves 16 are respectively arranged at the centers of the long sides on both sides of the upper annular semi-circular sleeve 9 and the lower annular semi-circular sleeve 17. The convex wing 15 is trapezoidally designed with a top side length of 15 mm, a bottom side length of 16 mm, and a height of 5 mm. The groove 16 is rectangularly designed with a width of 15 mm and a depth of 5 mm.

[0046] In the present invention, water-stop platforms 10 are provided at both ends of the lower annular semi-circular sleeve 17. A flow-stabilizing groove 11 and a water-collecting groove 13 are arranged inside the lower annular semi-circular sleeve 17. A plurality of second outer cavity water outlet holes 18 are evenly distributed on the water-stop platform 10 close to the water-collecting groove 13, and the second outer cavity water outlet holes 18 are arranged in a semi-circular shape. The dimensions of the flow-stabilizing groove 11, the water-collecting groove 13, the water-stop platform 10, and the second outer cavity water outlet holes 18 of the lower annular semi-circular sleeve 17 are the same as those of the flow-stabilizing groove 11, the water-collecting groove 13, the water-stop platform 10, and the first outer cavity water outlet holes 14 of the upper annular semi-circular sleeve 9.

[0047] The convex wings 15 of the upper annular semi-circular sleeve 9 are combined with the grooves 16 of the lower annular semi-circular sleeve 17, and the grooves 16 of the upper annular semi-circular sleeve 9 are combined with the convex wings 15 of the lower annular semi-circular sleeve 17 to form the flow-through outer cavity 2 by splicing. Since the width of the convex groove 15 is slightly larger than the width of the groove 16, the friction force can be increased by extrusion deformation to achieve the stable connection between the upper annular semi-circular sleeve 9 and the lower annular semi-circular sleeve 17.

[0048] In the present invention, a branch pipe 22 is further included. A plurality of capillary pipes 3 are connected to the outside of the branch pipe 22. A valve 23 is provided at the connection of each capillary pipe 3 and the branch pipe 22. On the side of the valve 23 away from the branch pipe 22, a capillary pipe initial section water injector 24, a capillary pipe middle section water injector 25, and a capillary pipe end section water injector 26 are arranged in sequence from near to far. The capillary pipe initial section water injector 24, the capillary pipe middle section water injector 25, and the capillary pipe end section water injector 26 respectively correspond to the capillary pipe first section energy dissipation outer cavity 19, the capillary pipe middle section energy dissipation outer cavity 20, and the capillary pipe end section energy dissipation outer cavity 21, and the number of teeth of their tooth-shaped maze flow channel sections 12 is 20 teeth, 16 teeth, and 12 teeth respectively.

[0049] Embodiment:

[0050] The present invention relates to a stepped energy dissipation active compensation suitable low-pressure drip irrigation water injector, which includes a flow-through inner cavity 1 and a flow-through outer cavity 2 with a tooth-shaped maze flow channel structure. A strip-shaped patch 4 is fixedly arranged on the inner wall of the flow-through inner cavity 1. An inner cavity water outlet hole 5 is provided on the pipe wall of the capillary pipe 3. The inner cavity water outlet hole 5 adopts a circular structure with an inner diameter of 1.6 mm. The flow-through inner cavity 1 and the flow-through outer cavity 2 are communicated through the inner cavity water outlet hole 5. The water flow first undergoes primary energy dissipation through the tooth-shaped maze flow channel unit 7 fixedly attached to the inner wall of the flow-through inner cavity 1, flows out through the inner cavity water outlet 5 and enters the tooth-shaped maze flow channel section 12 tightly attached to the outer wall of the capillary pipe 3 for secondary energy dissipation, and finally drips out from the water injector through the second outer cavity water outlet hole 18.

[0051] The capillary tube 3 is made of PE material with a thickness of not less than 0.08 mm. The strip-shaped patch 4 is tightly attached to the inner wall of the capillary tube 3 through an integrated thermoplastic molding technology, and the side of the patch flow channel faces the tube wall direction. The strip-shaped patches 4 are arranged at equal intervals of 30 - 50 cm along the capillary tube 3. The water inlet of the strip-shaped patch is the grid-shaped water inlet 6 of the strip-shaped patch, with a size of 10.4 mm × 3 mm. After the water flows through the toothed maze flow unit 7, it enters the patch outlet groove 8 at the end of the patch, and the patch outlet groove 8 is close to the inner cavity outlet hole 5 of the capillary tube 3. Another remarkable feature of the strip-shaped patch 4 is that the flow-through inner cavity 1 only completes 30% - 50% of the total energy dissipation of the emitter. Therefore, a larger flow channel size can be selected. The minimum flow-through cross-section of the flow channel is at the arc-shaped symmetric flow-through groove, with a width of 1 mm, and it is not easy to generate blockage and deposition of particulate matter. Therefore, the flow-through inner cavity 1 has strong anti-blocking ability.

[0052] The flow-through outer cavity 2 includes an upper annular semi-circular sleeve 9 and a lower annular semi-circular sleeve 17, and the upper annular semi-circular sleeve 9 and the lower annular semi-circular sleeve 17 are tightly attached to the outer wall of the capillary tube 3 in a nested manner. The steady flow groove 11 of the lower annular semi-circular sleeve 17 and the upper annular semi-circular sleeve 9 forms a closed water storage cavity after being closed, and the water collecting groove 13 of the lower annular semi-circular sleeve 17 and the upper annular semi-circular sleeve 9 forms a closed water collecting cavity after being closed, which plays a role in stabilizing the flow of the water flowing out from the inner cavity outlet.

[0053] The two ends of the upper annular semi-circular sleeve 9 are provided with water stop platforms 10. In the middle section of the upper annular semi-circular sleeve 9, there is a toothed maze flow channel section 12. The tooth angle of the toothed maze flow channel section 12 is 60°, the flow channel width is 0.9 mm, the tooth pitch is 2.3 mm, the tooth bottom distance is 0.70 mm, the tooth width is 1.62 mm, the flow channel depth is 0.9 mm, and the tooth tip difference is 0.2 mm. One side of the toothed maze flow channel section 12 is the steady flow groove 11, and the width of the steady flow groove 11 is 20 mm. The depth of the steady flow groove 11 recessed from the inner wall of the sleeve is 1.5 mm. The other side of the toothed maze flow channel section 12 is the water collecting groove 13, and the width of the water collecting groove 13 is 20 mm. The depth of the water collecting groove 13 recessed from the inside of the sleeve is 1.5 mm. The distance between the steady flow groove 11 and the water collecting groove 13 from the sleeve end is 5 mm. A plurality of first outer cavity outlet holes 14 are evenly distributed on the water stop platform 10 close to the water collecting groove 13.

[0054] The two ends of the lower annular semi-circular casing 17 are provided with water-stopping platforms 10. Inside the lower annular semi-circular casing 17, a flow-stabilizing groove 11 and a water-collecting groove 13 are arranged. A plurality of second outer cavity water outlet holes 18 are evenly distributed on the water-stopping platform 10 close to the water-collecting groove 13, and the second outer cavity water outlet holes 18 are arranged in a semi-circular shape. The dimensions of the flow-stabilizing groove 11, water-collecting groove 13, water-stopping platform 10, and second outer cavity water outlet holes 18 of the lower annular semi-circular casing 17 are the same as those of the flow-stabilizing groove 11, water-collecting groove 13, water-stopping platform 10, and first outer cavity water outlet holes 14 of the upper annular semi-circular casing 9, which have stronger anti-blocking ability, prevent negative pressure suction of mud, and prevent root invasion compared with circular water outlets.

[0055] Symmetrical convex wings 15 and grooves 16 are respectively arranged at the centers of the long sides on both sides of the upper annular semi-circular casing 9 and the lower annular semi-circular casing 17. The convex wing 15 is designed in a trapezoid shape, with the top side length of 15 mm, the bottom side length of 16 mm, and the height of 5 mm. The groove 16 is designed in a rectangular shape, with the width of 15 mm and the depth of 5 mm.

[0056] The convex wings 15 and grooves 16 are symmetrically arranged on the long sides of the upper and lower annular semi-circular casings 17 for snap connection. The convex wing 15 is designed in a trapezoid shape, with the top side length of 15 mm, the bottom side length of 16 mm, and the height of 5 mm. The groove 16 is designed in a rectangular shape, with the width of 15 mm and the depth of 5 mm. After the convex wing 15 is inserted into the groove 16, since the width of the convex wing 15 is slightly larger than that of the groove 16, it will squeeze the side wall of the groove 16, thereby increasing the friction force between the convex wing 15 and the groove 16. It can make the upper annular semi-circular casing 9 and the lower annular semi-circular casing 17 remain fixed on the outer wall surface of the capillary 3 and will not be misaligned, slipped or shifted due to operations such as dragging and laying of the pipeline.

[0057] The shape and size of the lower annular semi-circular casing 17 are the same as those of the upper annular semi-circular casing 9. The water-collecting groove 13 of the lower annular semi-circular casing 17 and the water-collecting groove 13 of the upper annular semi-circular casing 9 form a closed water storage cavity after being closed. The water flow flows out from the maze flow channel, passes through the water-collecting groove 13, and then flows out from the water outlet holes to the crop irrigation area. The flow-through outer cavity 2 is fixed on the outer wall of the capillary 3 in a snap-fastening form, and the outer cavity can be easily disassembled with the help of external force. Therefore, when the water injector is blocked, it is convenient to disassemble and wash the maze flow channel in the flow-through outer cavity 2. The flow-through inner cavity 1 is integrally processed and formed, which is convenient for production and processing. The flow channel width is designed according to large dimensions and has strong anti-blocking performance by itself. The above design points fully guarantee the anti-blocking performance of the drip irrigation injector of the present invention.

[0058] As Figure 10As shown in the figure, the flow-through outer cavity 2 of the upper annular semi-circular casing 9 adopts a differential energy dissipation design. A plurality of capillaries 3 are connected to the outside of the branch pipe 22. A valve 23 is provided at the connection of each capillary 3 and the branch pipe 22. On the side of the valve 23 away from the branch pipe 22, a capillary initial-stage emitter 24, a capillary middle-stage emitter 25, and a capillary end-stage emitter 26 are arranged in sequence from near to far. The capillary initial-stage emitter 24, the capillary middle-stage emitter 25, and the capillary end-stage emitter 26 respectively correspond to the capillary first-stage energy dissipation outer cavity 19, the capillary middle-stage energy dissipation outer cavity 20, and the capillary end-stage energy dissipation outer cavity 21. The number of teeth of the tooth-shaped maze flow channel section 12 is 20 teeth, 16 teeth, and 12 teeth respectively, completing 50%-70% of the total energy dissipation of the emitter. It can be known from the Darcy-Weisbach formula that the head loss in the capillary 3 increases with the increase of the distance from the inlet end of the capillary 3. To prevent the increase in the flow rate deviation of the drip emitter caused by the pressure drop caused by the head loss in the capillary 3, which will further lead to the reduction of the irrigation uniformity, in the middle and end sections of the capillary 3, a 16-tooth and a 12-tooth maze flow channel section 12 are respectively adopted to compensate for the energy loss along the inside of the capillary 3 by reducing the energy dissipation in the flow-through outer cavity 2, so as to achieve the effect of uniform outflow.

[0059] As Figure 10 shown, the flow-through outer cavity 2 adopts the principle of differential energy dissipation design. Theoretically, all the energy dissipated in the maze flow channel of the flow-through outer cavity 2 in the initial stage can be used to compensate for the frictional energy loss in the capillary 3, so that the maximum laying length of the capillary 3 to meet the flow rate deviation at the head and end is greatly increased, thus effectively reducing the laying length of the branch pipe 22 and reducing the total investment of the system pipeline.

[0060] As Figure 10 shown, according to the difference in the energy dissipation ability of the flow-through outer cavity 2 of the emitter of the present invention, the emitters are installed at the initial, middle, and end sections of the capillary 3 in the order of decreasing number of teeth of the maze flow channel, namely the capillary initial-stage emitter 24, the capillary middle-stage emitter 25, and the capillary end-stage emitter 26. It does not require the flow rate of a single emitter to be stable under variable pressure conditions, but an active pressure compensation design is carried out with the goal of uniform outflow of the entire capillary 3. In this example, a 3-level maze flow channel tooth number design is selected, and corresponding adjustments can be made according to the head loss along the way with the change of the laying length of the capillary 3.

[0061] As Figure 11 shown, the emitter with fewer teeth in the maze flow channel can obtain the same flow rate as the emitter with more teeth in the maze flow channel under relatively high pressure conditions under relatively low pressure conditions, indicating that the active compensation design adopted by the present invention achieves the goal of uniform outflow at low pressure.

[0062] As Figure 12The following shows the simulation results of the pressure change of the graded pressure compensation flow path in the outer cavity of the water applicator of this embodiment. At the same working pressure, the energy dissipation of the inner flow cavity 1 gradually increases with the decrease of the number of teeth in the outer cavity labyrinth flow path, indicating that the graded energy dissipation design adopted in the present invention achieves the goal of uniform low-pressure outflow.

[0063] As Figures 13-14 shown, the following shows the change of the discharge along the lateral 3 of the drip irrigation water applicator of this embodiment and the turbulent flow drip irrigation water applicator without compensation function. Obviously, affected by the head loss along the lateral 3, the flow rate of the turbulent flow drip irrigation water applicator without compensation function shows a decreasing trend along the way. The flow rate deviation of the inlaid patch type and side wing labyrinth type drip heads at the beginning and end reaches 25.9% and 25.6% respectively, which can no longer meet the requirements of the national standard "Technical Standard for Micro-irrigation Engineering" for the flow rate deviation of drip heads. However, the maximum flow rate deviation rate of the entire lateral 3 of the drip irrigation water applicator of this embodiment is only 5.67%, and the outflow uniformity is significantly improved.

[0064] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention, and any reference signs in the claims should not be regarded as limiting the claims involved.

[0065] The above is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter, comprising a flow-through inner cavity (1) and a flow-through outer cavity (2), characterized in that: The overcurrent inner cavity (1) and the overcurrent outer cavity (2) are respectively arranged corresponding to the inner side and the outer side of the capillary tube (3); A strip-shaped patch (4) is fixedly arranged on the inner wall of the overcurrent inner cavity (1). An inner cavity water outlet hole (5) is arranged on the tube wall of the capillary tube (3). The overcurrent inner cavity (1) and the overcurrent outer cavity (2) are communicated through the inner cavity water outlet hole (5); The overcurrent outer cavity (2) includes an upper annular semi-circular sleeve (9) and a lower annular semi-circular sleeve (17). The upper annular semi-circular sleeve (9) and the lower annular semi-circular sleeve (17) are tightly attached to the outer wall of the capillary tube (3) in a nested manner; Stop platforms (10) are arranged at both ends of the upper annular semi-circular sleeve (9). A toothed labyrinth flow channel section (12) is arranged in the middle section of the upper annular semi-circular sleeve (9). One side of the toothed labyrinth flow channel section (12) is a steady flow groove (11), and the other side of the toothed labyrinth flow channel section (12) is a water collecting groove (13). A plurality of first outer cavity water outlet holes (14) are evenly distributed on the stop platform (10) close to the water collecting groove (13).

2. A stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter according to claim 1, characterized in that: The toothed labyrinth flow channel in the strip-shaped patch (4) is composed of a plurality of toothed labyrinth flow channel units (7), and the toothed labyrinth flow channel is arranged in two rows at equal intervals in parallel.

3. The stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter according to claim 2, wherein: One end of the upward toothed labyrinth flow channel is connected with a grid-shaped water inlet (6). The other end of the upward toothed labyrinth flow channel is connected with the downward toothed labyrinth flow channel through a smooth arc chamfer. The other end of the downward toothed labyrinth flow channel is connected with a patch water outlet groove (8). The patch water outlet groove (8) is connected with the steady flow groove (11) through the inner cavity water outlet hole (5).

4. A stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter according to claim 1, characterized in that: Stop platforms (10) are arranged at both ends of the lower annular semi-circular sleeve (17). A steady flow groove (11) and a water collecting groove (13) are arranged inside the lower annular semi-circular sleeve (17). A plurality of second outer cavity water outlet holes (18) are evenly distributed on the stop platform (10) close to the water collecting groove (13).

5. The stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter according to claim 1, wherein: Symmetric convex wings (15) and grooves (16) are respectively arranged at the centers of the long sides on both sides of the upper annular semi-circular sleeve (9) and the lower annular semi-circular sleeve (17). The convex wing (15) of the upper annular semi-circular sleeve (9) is combined with the groove (16) of the lower annular semi-circular sleeve (17). The groove (16) of the upper annular semi-circular sleeve (9) is combined with the convex wing (15) of the lower annular semi-circular sleeve (17) to splice and form the overcurrent outer cavity (2).

6. A stepped energy dissipation active compensation suitable low-pressure drip irrigation emitter according to claim 1, characterized in that: It further includes a branch pipe (22). A plurality of capillary tubes (3) are connected to the outside of the branch pipe (22). A valve (23) is arranged at the connection of each capillary tube (3) and the branch pipe (22). A capillary tube initial section water injector (24), a capillary tube middle section water injector (25), and a capillary tube end section water injector (26) are sequentially arranged from near to far on the side of the valve (23) away from the branch pipe (22).

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