A kind of drip irrigation tape of the form of anti-negative suction bidirectional hedge flow channel and its preparation method
By optimizing the anti-negative suction bidirectional counter-current flow channel structure and materials, the clogging and mechanical performance problems of thin-walled drip irrigation tape under shallow burial conditions have been solved, achieving longer laying lengths and lower costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- INNER MONGOLIA UNIVERSITY
- Filing Date
- 2025-03-12
- Publication Date
- 2026-07-21
AI Technical Summary
Existing thin-walled drip irrigation tapes are prone to negative pressure sludge suction and blockage under shallow burial conditions, have short laying lengths, poor mechanical properties, and high costs, making it difficult to meet the needs of buried drip irrigation systems.
The design incorporates a bidirectional anti-negative suction flow channel structure, including forward and reverse flow channels. By combining specific material formulations and optimizing parameters such as channel depth, width, and arc radius, the hydraulic performance is enhanced while reducing manufacturing costs.
It effectively prevents negative pressure sludge suction from clogging, increases the laying length, reduces the investment cost of system equipment, and improves the mechanical and hydraulic properties of drip irrigation tape.
Smart Images
Figure CN120226581B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of drip irrigation tape technology, specifically, it relates to a drip irrigation tape with a bidirectional anti-negative suction flow channel and its preparation method. Background Technology
[0002] Drip irrigation technology has achieved remarkable development in my country, bringing significant benefits such as water conservation, increased yields, and higher incomes through its large-scale application in field irrigation. Currently, thin-walled drip irrigation tape remains the most important application form of drip irrigation technology in my country's field irrigation sector. However, as the technology is gradually promoted, its application scope is expanding, moving from traditional surface laying to shallow-buried irrigation. This has also created some new problems. First, the negative pressure suction during shallow-buried drip irrigation leads to severe clogging. Second, the current thin-walled drip irrigation tape has a large flow rate but short laying length, resulting in low irrigation uniformity, high difficulty in mechanized operation, and high investment costs for intelligent equipment. Finally, the current thin-walled drip irrigation tape is mainly made of recycled materials, making it difficult to meet the high tensile strength requirements of automatic pipe laying and retraction. Therefore, there is a need to develop a drip irrigation tape with a bidirectional counter-current flow channel design to prevent negative suction.
[0003] Currently, numerous experts and scholars have conducted relevant research on shallow-buried thin-walled drip irrigation tape. Jilin Provincial Water-Saving Irrigation Development Co., Ltd. has proposed a buried single-wing labyrinth drip irrigation tape (patent number: ZL2020219889511). Its key feature is the addition of a water bag frame and rubber bag structure to the outside of the drip irrigation tape body. This allows the water bag frame and rubber bag to inflate simultaneously with water addition to the drip irrigation tape body, increasing the width on both sides and preventing the drip irrigation tape body from tipping over. An anti-corrosion layer is added to the inner side of the base layer of the drip irrigation tape body, enabling it to resist the acidity and alkaliness in fertilizers and extending the service life of the drip irrigation tape body. However, this invention has a relatively complex structure and high manufacturing cost, posing a significant challenge for agriculture with low economic benefits. Xinjiang Tianye (Group) Co., Ltd. has proposed a single-wing labyrinth drip irrigation tape with an anti-clogging outlet (patent number: ZL2015200810314). Its features include a drip irrigation tape body and side wings. The side wings have labyrinth channels, an inlet, and an outlet. The inlet connects the main flow channel of the drip irrigation tape body to one end of the labyrinth channel on the side wing, and the outlet connects to the other end of the labyrinth channel on the side wing. The outlet has a slit-type structure with a rounded rectangular cross-section. However, under shallow burial conditions, soil pressure disrupts the original negative pressure gas movement trajectory, making it difficult to achieve a good anti-clogging effect. In summary, existing products have not addressed the problems of severe negative pressure sludge suction clogging, short laying distance, and poor pipe wall mechanical properties caused by thin-walled drip irrigation tapes used in underground burial. There is an urgent need to develop a bidirectional, counter-current flow channel drip irrigation tape to prevent negative suction. Summary of the Invention
[0004] In view of the above-mentioned problems in the existing technology, the purpose of the present invention is to provide a drip irrigation tape with a bidirectional anti-negative suction flow channel and its preparation method, which can increase the laying length of the drip irrigation tape and improve the mechanical properties of the pipe wall without significantly increasing the cost of the drip irrigation tape.
[0005] To solve the above problems, the technical solution adopted by the present invention is as follows:
[0006] A drip irrigation tape in the form of a bidirectional anti-negative pressure flow channel includes drip irrigation tape wall ribs, an inlet and an outlet, with a positive flow channel structure and an anti-negative pressure flow channel structure connected sequentially between the inlet and the outlet.
[0007] The forward flow channel structure includes a wave-shaped forward main flow channel composed of several straight forward inlet sections connected end to end, and at the end of each forward inlet section, there is a forward side flow channel that guides the flow back to the beginning of the forward inlet section. Two adjacent forward side flow channels are located on both sides of the forward main flow channel.
[0008] The anti-negative pressure channel structure has the same shape as the forward channel structure but in the opposite direction, forming a wave-shaped reverse side channel composed of several straight reverse inlet sections connected front and back, and a reverse main channel located on both sides of the reverse side channel.
[0009] The end of the forward main flow channel is the beginning of the reverse side flow channel.
[0010] Furthermore, the channel depth of the positive flow channel structure and the anti-negative pressure flow channel structure ranges from 0.3 to 1.2 mm, the channel width ranges from 0.3 to 1.4 mm, the outer arc radius ranges from 0.6 to 3.2 mm, the inner arc radius ranges from 0.3 to 1.0 mm, and the boss length ranges from 0.3 to 1.2 mm.
[0011] Furthermore, the drip irrigation tape wall forms an angle of 5-30° with the edge of the drip irrigation tape, which is consistent with the angle between the drip irrigation tape and the ground during pipe laying and pipe unwinding.
[0012] Furthermore, the preparation method of the drip irrigation tape includes using 5-15% by weight of low-density polyethylene virgin material, 15-30% of greenhouse film recycled material, and 50-70% of secondary recycled drip irrigation tape material as raw materials, and using 0.1-1% of light stabilizer, 1-5% of polyethylene wax, 2-5% of calcium carbonate filler, and 0.5-2% of color masterbatch as additives.
[0013] A method for preparing a drip irrigation tape with a bidirectional anti-negative suction flow channel includes using 5-15% by weight of low-density polyethylene virgin material, 15-30% of greenhouse film recycled material, and 50-70% of secondary recycled drip irrigation tape material as raw materials, and using 0.1-1% of light stabilizer, 1-5% of polyethylene wax, 2-5% of calcium carbonate filler, and 0.5-2% of color masterbatch as additives.
[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0015] (1) This invention proposes a bidirectional countercurrent flow channel form of drip irrigation tape with anti-negative suction. The reverse flow channel structure at the tail end has the function of anti-negative suction, while the forward flow channel structure at the front end has high hydraulic performance and high mechanical performance with reinforced drip irrigation tape wall. At the same time, with the addition of modified drip irrigation tape material, the manufacturing cost is reduced, and the problems of negative pressure mud blockage, short laying length and poor mechanical performance of traditional shielded drip irrigation tape after being used in buried systems are solved.
[0016] (2) The bidirectional counter-flow channel structure with high hydraulic performance designed in this invention clarifies the structural parameter optimization design method and specific control threshold. Compared with the traditional flow channel form, this design has a strong water flow counter-flow effect, and there is a blockage material accumulation area at the corner, which can reduce the impact of the accumulation of blockage material on the drip irrigation tape outflow within the cycle, reduce the overall flow of the drip irrigation tape, thereby increasing the laying length and reducing the investment cost of valves and other equipment in the system.
[0017] (3) The reverse flow channel structure designed in this invention has a mainstream area that is not the same as the mainstream area when the flow is reversed. This can reduce the probability of blockage material entering the flow channel unit and blocking it, thereby effectively alleviating the blockage problem caused by negative pressure sludge suction.
[0018] (4) The present invention also proposes a reinforcement scheme for the drip irrigation tape wall, so that the drip irrigation tape wall and the drip irrigation tape side are at an angle of 5-30 degrees, which is consistent with the angle between the drip irrigation tape and the ground when laying and retracting the pipe, so as to minimize the deformation caused by the tension of the drip irrigation tape during the laying and retracting process, and at the same time, reduce the overall deformation of the drip irrigation tape caused by the fluctuation of water flow under different pressures.
[0019] (5) The material preparation method for drip irrigation tape of this structure proposed in this invention can effectively reduce the manufacturing cost of drip irrigation tape. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the structure of the drip irrigation tape described in this invention;
[0021] Figure 2 This is a schematic diagram of the forward flow channel structure;
[0022] Figure 3 Schematic diagram of the internal flow characteristics of different flow channels;
[0023] Figure 4 A schematic diagram illustrating the forward and reverse flow characteristics of a negative pressure flow channel structure;
[0024] Figure 5 A schematic diagram comparing the flow rates under normal flow and negative suction in the flow channel;
[0025] In the diagram: 1-Drip irrigation tape wall reinforcement; 2-Inlet; 3-Forward flow channel structure; 31-Forward inlet section; 32-Forward main flow channel; 33-Forward side flow channel; 4-Anti-negative pressure flow channel structure; 41-Reverse inlet section; 42-Reverse side flow channel; 43-Reverse main flow channel; 5-Outlet. Detailed Implementation
[0026] The present invention will be further described below with reference to specific embodiments.
[0027] like Figure 1 As shown, the drip irrigation tape of the present invention in the form of a bidirectional anti-negative pressure flow channel includes a drip irrigation tape wall rib 1, an inlet 2 and an outlet 5, and between the inlet 2 and the outlet 5, a positive flow channel structure 3 and an anti-negative pressure flow channel structure 4 are connected in sequence.
[0028] Specifically, such as Figure 2 As shown, the forward flow channel structure 3 includes a wavy forward main flow channel 32 composed of several straight forward inlet sections 31 connected end to end. At the end of each forward inlet section 31, a forward side flow channel 33 is provided to guide the flow back to the beginning of the forward inlet section 31. Two adjacent forward side flow channels 33 are located on both sides of the forward main flow channel 32. Through the above structural design, the flow rate can be reduced, the hydraulic performance can be enhanced, and thus the laying length of the drip irrigation tape can be increased.
[0029] The flow channel structure design of this scheme ( Figure 3 (a) , with toothed flow channel structure ( Figure 3 (b) Rectangular flow channel structure Figure 3 (c) Flow characteristics for example Figure 3 As shown, the toothed and rectangular channels have a smaller velocity difference between the mainstream and non-mainstream zones to ensure anti-clogging capabilities, resulting in lower head loss per channel unit. However, since single-wing labyrinth drip irrigation tapes are generally manufactured using an adsorption molding process, the tooth tips have rounded corners, leading to a longer channel length and higher flow rate when this channel design is applied to single-wing labyrinth drip irrigation tapes.
[0030] The flow channel structure designed in this scheme employs a method that leaves a blockage accumulation zone at the corners. This enhances the flow velocity in the main flow zone and reduces the flow velocity in the blockage accumulation zone, concentrating the blockage material in the water source within the accumulation zone. This reduces the impact of accumulated blockage material on the drip irrigation tape outflow in a short period, thereby reducing the overall flow rate of the drip irrigation tape, increasing the laying length, and reducing the investment costs of valves and other equipment in the system. This is also more suitable for the application conditions of thin-walled drip irrigation tape, a disposable product.
[0031] The anti-negative pressure flow channel structure 4 has the same shape as the forward flow channel structure 3, but in the opposite direction. It forms a wave-shaped reverse side flow channel 42 composed of several straight reverse inlet sections 41 connected end-to-end, and reverse main flow channels 43 located on both sides of the reverse side flow channel 42. The end of the forward main flow channel 32 is the beginning of the reverse side flow channel 42. Its negative suction effect causes most of the dirt drawn in by the reverse flow to reside in the side area, which is inconsistent with the mainstream area of the forward flow.
[0032] The flow characteristics of the anti-negative pressure flow channel structure designed in this scheme are as follows: Figure 4 As shown, under an inlet pressure of 0.1 MPa, when the water flows in the forward direction along the channel ( Figure 4 In case (a), the mainstream flow region is located in the middle of the flow channel, while the side regions are non-mainstream regions, resulting in relatively small head loss. However, when the flow reverses, the flow characteristics under an inlet pressure of 0.1 MPa are as follows: Figure 4 As shown in (b), the mainstream flow zone is located on the side of the channel, while the central area is a non-mainstream zone, resulting in significant head loss. Therefore, when reverse flow is achieved, the large flow resistance makes it difficult for the flow to enter multiple channel units. In the initial unit structure, most of the dirt drawn in by the reverse flow is located on the side, not affecting the passage of the forward flow. Simultaneously, when the drip irrigation tape generates anti-negative suction, its reverse flow inlet pressure is no greater than 0.02 MPa. Numerical simulations under real-world conditions are used to compare the flow rate differences, such as... Figure 5 As shown, under this flow channel unit, the forward flow rate is 8.92 L / h, and when negative suction occurs, the flow rate is only 0.36 L / h. In summary, its structure has a good anti-negative suction effect.
[0033] Based on the above-mentioned channel structure design, this scheme also compared different channel structure parameters to obtain their structural control thresholds. The flow regime index was used as the hydraulic performance indicator, with a flow regime index closer to 0.5 being better. Referring to the indications in section 2, where S is the channel depth, K is the channel width, R1 is the outer arc radius, R2 is the inner arc radius, and L is the boss length, the ratio of negative suction flow under negative pressure to positive flow flow was used as the anti-negative suction effect indicator, with a ratio closer to 0 being better. Using these two as control indicators, numerical simulations were conducted for comparison. The final results showed that the channel depth control threshold was 0.3-1.2 mm, the channel width control threshold was 0.3-1.4 mm, the outer arc radius control threshold was 0.6-3.2 mm, the inner arc radius control threshold was 0.3-1.0 mm, and the boss length control threshold was 0.3-1.2 mm.
[0034] This invention also proposes a method for preparing drip irrigation tape with a bidirectional anti-negative suction flow channel, comprising 5-15% by weight of virgin low-density polyethylene, 15-30% of recycled greenhouse film, and 50-70% of recycled drip irrigation tape as raw materials, and 0.1-1% of light stabilizer, 1-5% of polyethylene wax, 2-5% of calcium carbonate filler, and 0.5-2% of color masterbatch as additives. This formula can effectively reduce the manufacturing cost of drip irrigation tape.
[0035] Example:
[0036] This embodiment requires the development of a 1.0L / h drip irrigation tape product with anti-negative suction bidirectional countercurrent flow channel for shallow underground burial.
[0037] First, based on the optimized design method of the bidirectional counter-current flow channel forward and reverse flow structural unit, suitable product parameter control thresholds were determined. Using the flow index, forward flow rate, and negative suction flow rate under negative pressure as comparative indicators, numerical simulation was conducted. It was found that the optimal flow channel depth was 0.4 mm, the flow channel width was 0.4 mm, the outer arc radius was 1.6 mm, the inner arc radius control threshold was 0.6 mm, and the boss length was 0.5 mm. At this point, the forward flow rate was greater than the outflow flow rate, and the ratio of negative suction flow rate to forward flow rate under negative pressure was relatively small. At the same time, the flow index reached 0.50, resulting in the optimal hydraulic performance.
[0038] Secondly, to improve the tensile strength of the pipe wall, the surface of the drip irrigation tape is reinforced to ensure a 15-degree angle between the tape wall and the edge, consistent with the angle between the tape and the ground during laying and unwinding. Simultaneously, the material formulation of the drip irrigation tape consists of 10% virgin low-density polyethylene, 20% recycled greenhouse film, and 65% recycled drip irrigation tape; its additives include 0.5% light stabilizer, 1% polyethylene wax, 3% calcium carbonate filler, and 0.5% color masterbatch.
Claims
1. A drip irrigation tape in the form of a negative suction resistant bi-directional counterflow channel, comprising a drip irrigation tape wall, a water inlet and a water outlet, characterized in that, A positive flow channel structure and a negative pressure prevention flow channel structure are connected sequentially between the water inlet and the water outlet; The forward flow channel structure includes a wave-shaped forward main flow channel composed of several straight forward inlet sections connected end to end, and at the end of each forward inlet section, there is a forward side flow channel that guides the flow back to the beginning of the forward inlet section. Two adjacent forward side flow channels are located on both sides of the forward main flow channel. The anti-negative pressure channel structure has the same shape as the forward channel structure but in the opposite direction, forming a wave-shaped reverse side channel composed of several straight reverse inlet sections connected front and back, and a reverse main channel located on both sides of the reverse side channel. The end of the main forward flow channel is the beginning of the reverse side flow channel. Both the main forward flow channel structure and the anti-negative pressure flow channel structure have a blockage material accumulation area. The blockage material in the water source is concentrated in the blockage material accumulation area, which increases the flow velocity of the main forward side flow channel and reduces the flow velocity of the blockage material accumulation area, thereby reducing the impact of blockage material accumulation on the drip irrigation belt outflow. When the water flows forward along the channel, the main flow area of the anti-negative pressure channel structure is the reverse side channel, and the reverse main flow channel is the non-main flow area. At this time, the head loss is small. The forward flow rate of the flow channel can reach 8.92 L / h, while the reverse flow rate is only 0.36 L / h when a negative suction effect is generated. The drip irrigation tape has an angle of 5-30° between its pipe wall and the side of the drip irrigation tape, which is consistent with the angle between the drip irrigation tape and the ground when laying and retracting the pipe. The preparation method of the drip irrigation tape includes using 5-15% by weight of low-density polyethylene virgin material, 15-30% of greenhouse film recycled material, and 50-70% of secondary recycled drip irrigation tape material as raw materials, and using 0.1-1% of light stabilizer, 1-5% of polyethylene wax, 2-5% of calcium carbonate filler, and 0.5-2% of color masterbatch as additives. Different flow channel structural parameters were compared to obtain their structural control thresholds: the flow regime index was used as the hydraulic performance indicator, with a flow regime index closer to 0.5 being better; the ratio of negative suction flow rate to positive flow rate under negative pressure was used as the anti-negative suction effect indicator, with a ratio closer to 0 being better; using the aforementioned hydraulic performance indicator and anti-negative suction effect indicator as control indicators, the parameter control thresholds were compared through numerical simulation to obtain the following: The flow channel depth of the positive flow channel structure and the anti-negative pressure flow channel structure ranges from 0.3 to 1.2 mm, the flow channel width ranges from 0.3 to 1.4 mm, the outer arc radius ranges from 0.6 to 3.2 mm, the inner arc radius ranges from 0.3 to 1.0 mm, and the boss length ranges from 0.3 to 1.2 mm.