A narrow-band-shaped spraying area jet nozzle for the field of farmland water-saving irrigation

Abstract

The present invention discloses a narrow-band spraying area jet nozzle for the field of farmland water-saving irrigation. The nozzle mainly consists of three sections: a three-dimensional special-shaped nozzle, a variable-diameter rectifying pipe, and a diversion elbow. Among them, the three-dimensional special-shaped nozzle is located at the forefront and is the energy converter of the narrow-band spraying area jet nozzle; the variable-diameter rectifying pipe is located in the middle section and is the liquid rectifier and speed increaser of the narrow-band spraying area jet nozzle; the diversion elbow is located at the incoming flow end and is the water inlet connector of the narrow-band spraying area jet nozzle of the present invention. It should be particularly noted that in addition to being used for fixed-point positioning sprinkler irrigation, since it does not need to enter the field during operation, the mobile sprinkler irrigation machines and irrigation units equipped with the narrow-band spraying area jet nozzle described in the present invention are particularly suitable for performing farmland sprinkler irrigation operations on non-planting areas such as tractor roads and field roads, and have unique advantages such as water and energy conservation, non-rolling of soil, and non-rolling of crop seedlings.

Description

Technical Field

[0001] The present invention belongs to the field of agricultural water-saving irrigation, and particularly relates to a narrow-band spraying area water-saving irrigation sprinkler head that does not require field spraying operation. Background Art

[0002] Compared with traditional irrigation modes such as flood irrigation and furrow irrigation, the sprinkler irrigation method is more water-saving and has better adaptability to farmland. As a key component and important irrigation device of the agricultural sprinkler irrigation system, the main performance parameters of the sprinkler head, such as its range and uniformity, not only determine irrigation indexes such as water utilization rate and operation efficiency, but ultimately will affect the yield, quality of crops and farmers' income.

[0003] The spraying area refers to the land area with a certain geometric shape wetted by the sprinkler head jet; different forms of sprinkler heads have different spraying areas due to different nozzle designs. At present, most farmland sprinkler irrigation uses rocker-arm sprinkler heads with a circular outlet and driven by a certain structure to rotate intermittently and periodically. The methods are mainly divided into fixed and mobile types. The single-sprinkler spraying area of fixed sprinkler irrigation is circular. In actual use, a combined spraying mode is mostly adopted, and the latter has serious defects such as overspray in the overlapping area and missed spraying at the edge of the field block, and it is also difficult to greatly improve the uniformity. During mobile sprinkler irrigation operation, the unit must enter the field, which will cause rolling to the soil and crops and damage the field soil structure. Therefore, it is extremely urgent to develop a narrow-band spraying area jet sprinkler head that does not enter the field, does not require periodic back-and-forth scanning, has no rotating mechanism, and can spray a uniform water band in the jet direction.

[0004] Nan Jianfu et al. (CN 101497065A) disclosed a strip-shaped spraying sprinkler head containing a rotating structure such as a main shaft and a radial-flow closed impeller, which is suitable for strip-shaped water spraying for row crops to enter the field, and has relatively large structural dimensions. The special-shaped nozzle rotary magnetic jet polishing device of Cheng Haobo et al. (CN 102975124B) is mainly used for precision optical surface polishing; the special-shaped nozzle disclosed by Zhejiang Yitian Smart Kitchen Appliance Co., Ltd. (CN 107448988B) includes a special-shaped body and a groove, and is mainly used for gas stoves. After retrieval, no relevant reports have been found on a narrow-band spraying area jet sprinkler head that can be used in both fixed and mobile modes and can spray a uniform water band in the jet direction. Summary of the Invention

[0005] The purpose of the present invention is to provide a narrow-band spraying area agricultural water-saving irrigation jet sprinkler head to solve the problems raised in the above background art. To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A narrow-band-shaped spraying area farmland water-saving irrigation jet nozzle, which is composed of a diversion elbow (1), a reduced-diameter rectifying pipe (2), and a three-dimensional special-shaped nozzle (3) connected in sequence; among them, the three-dimensional special-shaped nozzle (3) is located at the front end of the nozzle and is the pressure energy-kinetic energy conversion and work component of the nozzle. It is a three-dimensional structure nozzle, and the ejection end of the three-dimensional structure nozzle is a three-dimensional special-shaped flow channel; the reduced-diameter rectifying pipe (2) is located in the middle section and is the liquid rectifying and speed-increasing device of the nozzle. It contains several strip-shaped rectifying fins (203) arranged circumferentially. The diversion elbow (1) is located at the incoming flow end and is the water inlet connector of the nozzle. The water outlet section of the diversion elbow (1) is designed as an elbow structure.

[0007] Furthermore, the overall structure from the nozzle inlet to the nozzle outlet (301) of the three-dimensional special-shaped nozzle (3) is a cylindrical-cone coupling structure. The nozzle jet orifice of the nozzle outlet (301) is a three-dimensional duckbill special-shaped grooved structure. Along the flow direction of the jet orifice, V-shaped grooves are opened at the bottom and front of the mid-plane. The groove openings gradually open outwards and upwards to form a fan-shaped jet of the water body in the proximal range mainly. Strip-shaped grooves are opened in the upper half of the mid-plane to form a beam-shaped jet of the water body in the distal range mainly; the interface between the V-shaped groove and the strip-shaped groove has a smooth transition, and they work together to promote the formation of a narrow-band-shaped range; after the fluid is ejected at a high speed in a narrow-band form by the three-dimensional special-shaped nozzle (3), a long strip-shaped narrow band (4) with uniform water volume distribution will be formed from near to far; by adjusting the flow rate, pressure and elevation angle of the nozzle inlet, different ranges and different sprinkler irrigation intensities can be achieved.

[0008] Furthermore, the outer diameter and inner diameter of the large-diameter end of the reduced-diameter rectifying pipe (2) are 42 mm and 30 mm respectively, and the outer diameter and inner diameter of the small-diameter end are 27 mm and 20 mm respectively. Six strip-shaped rectifying fins (203) are arranged circumferentially at the front end of the pipe inner wall.

[0009] Furthermore, the reduced-diameter rectifying pipe (2) and the diversion elbow (1) adopt a single-end face plus gasket O-ring sealing form, and are connected by 2 to 4 pre-tightening bolts (202) with self-pre-tightening force arranged on the outer circle.

[0010] Furthermore, the three-dimensional special-shaped nozzle (3) and the reduced-diameter rectifying pipe (2) are directly connected by a right-hand or left-hand mating thread (204) processed by mating turning. When installing, raw tape is wound inside or liquid sealant is applied to ensure the assembly coaxiality of the two.

[0011] Furthermore, standard metric or imperial threads (102) are designed and processed on the inner and outer surfaces of the water inlet (101) of the diversion elbow (1) to facilitate matching and connection with water inlet pipes of various specifications.

[0012] Further, the outer diameter and inner diameter of the diversion elbow (1) are 40 mm and 30 mm respectively. The water outlet section of the diversion elbow is designed as an elbow structure to adjust the liquid flow coming vertically upward from the water inlet (101) to a direction with a small elevation angle to the horizontal. A boss for installing and positioning the nozzle is machined in the middle section of the diversion elbow (1). The outer diameter of the boss is 50 mm and the width is 10 mm.

[0013] Further, in addition to being used for fixed-point sprinkler irrigation, since the operation can be carried out without the need to enter the field during operation, the nozzle is equipped on mobile sprinkler irrigation machines and irrigation units and is suitable for performing farmland sprinkler irrigation on non-planting areas such as farm roads and field roads.

[0014] The narrow-band-shaped spraying area farmland water-saving irrigation jet nozzle described in the present invention has the following beneficial effects:

[0015] (1) In addition to being used for fixed-point positioning sprinkler irrigation, since this irrigation mode can be carried out without entering the field during operation, the narrow-band-shaped spraying area jet nozzle described in the present invention can be installed on both sides of mobile sprinkler irrigation machines and irrigation units. Let the machine or unit slowly move along non-planting areas such as farm roads and field roads, and at the same time, the narrow-band-shaped spraying area jet nozzle performs farmland sprinkler irrigation operations on both sides in the horizontal and vertical directions of the travel, having unique advantages such as water saving, energy saving, not crushing the soil, and not rolling over crop seedlings. (2) The sprinkler irrigation range can be changed by adjusting parameters such as different inlet flow rates, inlet pressures, and nozzle elevation angles. (3) The sprinkler irrigation intensity, irrigation water volume, etc. can form a closed loop with the soil profile moisture sensor based on agricultural Internet of Things and the diagnostic model and irrigation prescription of other multi-source information, improving the accuracy of farmland crop irrigation and truly achieving water supply on demand. The irrigation water flow enters from the water inlet end of the diversion elbow, changes the flow direction through the diversion elbow, undergoes primary rectification and diameter reduction and speed increase by the variable-diameter rectification tube, and secondary flow control and energy conversion by the three-dimensional special-shaped nozzle, and finally shoots out at a high speed from the nozzle outlet in a special narrow-band form, and forms a long-strip-shaped narrow band with uniform water volume distribution from near to far; different ranges can be achieved by adjusting different inlet flow rates (i.e., speeds), inlet pressures, nozzle elevation angles, etc. Description of the Drawings

[0016] Figure 1 It is the main structure diagram of this narrow-band-shaped spraying area jet nozzle with 3 local cross-sections inside.

[0017] Figure 2 It is the isometric enlarged view of the three-dimensional special-shaped nozzle (3) of this narrow-band-shaped spraying area irrigation jet nozzle.

[0018] Figure 3 It is the isometric view of the variable-diameter rectification tube (2) of this narrow-band-shaped spraying area irrigation jet nozzle

[0019] Figure 4 It is the cross-sectional view of the variable-diameter rectification tube (2) (with several rectification fins inside).

[0020] Figure 5 Isometric enlarged view of the diversion elbow (1) of the narrow-band-shaped spraying area irrigation jet nozzle.

[0021] Figure 6 Is the contour map of the velocity change obtained after post-processing the numerical simulation of the internal flow field of the nozzle.

[0022] Figure 7 Is the contour map of the pressure change obtained after post-processing the numerical simulation of the internal flow field of the nozzle.

[0023] Figure 8 Is the schematic diagram of the narrow band formed by the sprinkler irrigation operation of the narrow-band-shaped spraying area irrigation jet nozzle.

[0024] Description of the markings in the figure: 1. Diversion elbow, 101. Inlet, 102. Thread, 103. Positioning ring; 2. Reducing rectifying pipe, 201. O-ring, 202. Pre-tightening bolt, 203. Rectifying fin, 204. Fitting thread; 3. Three-dimensional special-shaped nozzle, 301. Nozzle outlet; 4. Sprinkler irrigation narrow band. Specific implementation mode

[0025] To make the features and advantages of the present invention more understandable, the following combines the attached Figures 1 to 8 And specific embodiments to further illustrate the present invention, but the protection scope of the present invention is not limited thereto.

[0026] Figure 1 Is a design example of the narrow-band-shaped spraying area farmland water-saving irrigation jet nozzle of the present invention, with its rated working pressure P being 0.3 MPa, rated sprinkler irrigation flow rate Q being 10 m 3 / h, designed range S being 25 m, distal bandwidth ≤ 1 m, proximal bandwidth range ≥ 0.5 m, and the bandwidth difference between the distal end and the proximal end not being greater than 0.5 m.

[0027] As described above, the nozzle mainly consists of three sections: a three-dimensional special-shaped nozzle (3), a reducing rectifying pipe (2), and a diversion elbow (1).

[0028] Among them, the three-dimensional special-shaped nozzle (3) is located at the forefront and has the smallest volume. The actual structure is as Figure 2 Shown, is the energy converter of the narrow-band-shaped spraying area jet nozzle; the three-dimensional special-shaped flow channel at the nozzle outlet end is the core jet source for forming the characteristics of the narrow-band-shaped spraying area. Its structure design is optimized based on the numerical simulation of the flow field, and the equivalent diameter of the outflow surface at the jet outlet is 10 mm.

[0029] The reducing rectifying pipe (2) is located in the middle section. The actual structure is shown in Figure 3, with an outer diameter of 42 mm and an inner diameter of 30 mm at the large-diameter end, an outer diameter of 27 mm and an inner diameter of 20 mm at the small-diameter end, is the liquid rectifier and speed increaser of this narrow-band-shaped spraying area jet nozzle; there are 6 long strip-shaped rectifying fins (203) circumferentially arranged at the front end of the inner wall of the pipe, which can eliminate the turbulent vortices of the high-speed fluid medium from the diversion elbow and rectify it into a laminar flow structure with good directionality, uniform flow field distribution, and stable and regular flow pattern.

[0030] The diversion elbow (1) is located at the incoming flow end, and its actual structure is as Figure 5 shown. Its outer diameter and inner diameter are 40 mm and 30 mm respectively, and it is the water inlet connector of this narrow-band-shaped spraying area jet nozzle. The outlet section of the diversion elbow is designed as an elbow structure, which can adjust the liquid flow coming vertically upward from the inlet (101) to a direction with a small elevation angle to the horizontal. There is a boss for nozzle installation and positioning processed in the middle section of the diversion elbow (1), with an outer diameter of 50 mm and a width of 10 mm.

[0031] The three-dimensional special-shaped nozzle (3) is directly connected to the variable-diameter rectifying pipe (2) by M24 right-hand thread. When installing, PTFE tape is wound inside and liquid sealant is applied. It is necessary to conduct a pressure-holding test with a water pressure more than 1.5 times the rated working pressure of 0.3 MPa to ensure the reliability of the sealed connection; the internal thread of the three-dimensional special-shaped nozzle (3) and the external thread of the variable-diameter rectifying pipe (2) are machined by matching turning to ensure the straightness of assembly and the form tolerance of coaxiality above grade 7 for both.

[0032] The variable-diameter rectifying pipe (2) and the diversion elbow (1) are connected by single-end face sealing. An O-ring seal (201) with a size of 35×2.65 is added, and 2 pre-tightening bolts (202) of M8×10 are arranged on the outer ring to achieve connection and pre-tightening. The inner and outer surfaces of the water inlet (101) of the diversion elbow (1) are respectively designed with an M40 standard metric external thread with a length of 20 mm and an M30 standard metric internal thread (102) with a length of 20 mm, which is convenient for matching and connecting with the M40 internal thread and the M30 standard metric external thread.

[0033] When the irrigation water supply incoming flow enters the nozzle from the water inlet (101) of the diversion elbow (1) at a flow rate of 10 m 3 / h and a pressure of 0.3 MPa, it successively undergoes the flow direction change of the diversion elbow (1), the primary rectification and variable-diameter speed increase of the variable-diameter rectifying pipe (2), and the secondary flow control and energy form conversion of the three-dimensional special-shaped nozzle (3). Finally, it is ejected at high speed in the form of a narrow-band flow from the nozzle outlet (301) and forms a shape like Figure 6The long, narrow strip shows a uniform water volume distribution with a slightly diffused bandwidth. The range S reaches 24.5 m, with the distal narrow strip being 0.96 m and the proximal narrow strip being 0.53 m. The parameter errors are all less than ±5%, within the design requirements. Moreover, different ranges and narrow strip widths can be achieved by adjusting different inlet flows (i.e., inlet velocities), inlet pressures, nozzle elevation angles, etc.

[0034] The three-dimensional special-shaped nozzle (3) is optimized into a narrow strip-shaped spraying domain jet nozzle. The outer circular surface of the small-diameter end is conical. The nozzle opening is vertically provided with a three-dimensional duckbill-shaped special-shaped groove along the flow direction, which is a V-shaped cutting groove from inside to outside, and the groove opening gradually expands outwards and upwards. A strip-shaped cutting groove is provided in the upper part of the three-dimensional special-shaped nozzle (3), and the starting position extends backward a certain length or several distances in the oncoming flow direction, with a uniform width or a small diffusion angle structure from inside to outside. For the three-dimensional duckbill-shaped special-shaped groove, the cutting groove width at the outermost side of the upper strip-shaped groove is narrower than or equal to the maximum groove width of the V-shaped groove. The intersection line of the two groove structures has a smooth transition, and the combined action promotes the formation of a narrow strip-shaped jet surface with no obvious cross-sectional change, ensuring the irrigation uniformity coefficient. The product of the equivalent area of the upper strip-shaped groove and its average jet velocity is equal to the product of the equivalent area of the lower front V-shaped groove and its average jet velocity, respectively responsible for forming the water consumption required for jet irrigation of 50% of the total range at the distal end and 50% of the total range at the proximal end. By adjusting the equivalent area of the jet outlets of the two grooves and their velocity integrals, the proportion of the proximal fan-shaped jet and the distal beam-shaped jet in the total irrigation flow can be adjusted, but it is necessary to ensure the irrigation performance indicators such as the uniformity coefficient as a prerequisite.

[0035] Appendix Figure 7 This is a velocity change nephogram obtained from the post-processing of the numerical simulation of the internal flow field of the nozzle. It can be seen that from the nozzle inlet to the jet outlet, the velocity changes of each part are uniform and the gradient changes are stable. Appendix Figure 8 This is a pressure change nephogram obtained from the post-processing of the numerical simulation of the internal flow field of the nozzle. It can be seen that from the nozzle inlet to the jet outlet, the pressure changes of each part are uniform and the gradient changes are stable.

[0036] According to the basic requirements of farmland water-saving irrigation and combining with the actual situations of standardized farmland and ordinary fields, the main performance and structural parameters of the narrow-band jet nozzle to be invented are first determined. By using the characteristic parameters of the water jet and its motion trajectory equation, the basic principles of various water jets forming different spraying areas are studied comparatively, the basic principles, ideas and methods of forming a narrow-band spraying area are analyzed, and the corresponding mathematical model is established. By using the CAD three-dimensional modeling software, by appropriately simplifying and neglecting the weak structures that have little influence on the formation of the narrow-band spraying area or the performance of the nozzle, the physical models of the three-dimensional special-shaped nozzle (3), the variable-diameter rectifying pipe (2), and the diversion elbow (1) corresponding to each parameter table are uniformly established. By using the finite element analysis mesh generation tool and the CFD fluid dynamics calculation software Fluent, etc., on the basis of the grid independence check, the external flow field near the nozzle outlet (301) of the established three-dimensional special-shaped nozzle (3) and the internal flow field established by the internal part of the fluid of the three-dimensional special-shaped nozzle (3), the variable-diameter rectifying pipe (2), and the diversion elbow (1) are respectively completed for the VOF model multiphase flow numerical simulation calculation and the full flow field steady and unsteady numerical simulation calculation of each parameter group. The irrigation water flow enters the nozzle from the water inlet (101) of the diversion elbow (1) at a certain speed and pressure, successively passes through the flow direction change of the diversion elbow (1), the primary rectification and variable-diameter speed increase of the variable-diameter rectifying pipe (2), and the secondary flow control and energy form conversion of the three-dimensional special-shaped nozzle (3), and finally shoots out from the nozzle outlet (301) at a high speed in the form of a narrow-band flow, and forms a long narrow band (4) with uniform water volume distribution and slightly diffused bandwidth from near to far; by adjusting different inlet flow rates (i.e., speeds), inlet pressures, nozzle elevation angles, etc., different ranges can be achieved.

[0037] In summary, a narrow-band-shaped spraying area jet nozzle for the field of farmland water-saving irrigation according to the present invention. The nozzle mainly consists of three sections: a three-dimensional special-shaped nozzle, a variable-diameter rectifying pipe, and a diversion elbow. The three-dimensional special-shaped nozzle is located at the forefront and is the energy converter of the narrow-band-shaped spraying area jet nozzle; the variable-diameter rectifying pipe is located in the middle section and is the liquid rectifying and speed-increasing device of the narrow-band-shaped spraying area jet nozzle; the diversion elbow is located at the incoming flow end and is the water inlet connector of the narrow-band-shaped spraying area jet nozzle of the present invention. The three-dimensional special-shaped nozzle is directly connected to the variable-diameter rectifying pipe by threads. The internal thread of the special-shaped nozzle and the external thread of the variable-diameter rectifying pipe are machined by matching, which can ensure the assembly coaxiality; the variable-diameter rectifying pipe and the diversion elbow adopt a single-end face plus gasket O-ring sealing form, and 2 to 4 self-tightening threaded connections are arranged on the outer ring; the inner and outer surfaces of the water inlet end of the diversion elbow are processed with standard metric or imperial threads, which is convenient for matching and connecting with water inlet pipes of various specifications. The irrigation water flow enters from the water inlet end of the diversion elbow, changes the flow direction through the diversion elbow, is rectified and the diameter is changed and the speed is increased by the variable-diameter rectifying pipe, and the three-dimensional special-shaped nozzle controls the flow and converts the energy for the second time. Finally, it is ejected from the nozzle outlet at a high speed in a special narrow-band form and forms a long narrow band with uniform water distribution from near to far; different ranges can be achieved by adjusting different inlet flow rates (i.e., speeds), inlet pressures, nozzle elevation angles, etc. It should be particularly noted that in addition to being used for fixed-point positioning sprinkler irrigation, since it does not need to enter the field during operation, the mobile sprinkler irrigation machine and irrigation unit equipped with the narrow-band-shaped spraying area jet nozzle of the present invention are particularly suitable for performing farmland sprinkler irrigation operations on non-planting areas such as tractor roads and field roads, and have unique advantages such as water saving, energy saving, not crushing the soil, and not crushing crop seedlings.

[0038] Finally, it should be understood that the above embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. After reading the present invention, various equivalent forms of modification of the present invention by those skilled in the art all fall within the scope defined by the appended claims of this application.

Claims

1. A narrow-band-shaped spraying area jet nozzle for the field of farmland water-saving irrigation, characterized in that: The nozzle is composed of a diversion elbow (1), a reduced-diameter flow rectifying pipe (2), and a three-dimensional special-shaped nozzle (3) connected in sequence. Among them, the three-dimensional special-shaped nozzle (3) is located at the front end of the nozzle and is the component for converting pressure energy into kinetic energy and doing work of the nozzle. It is a three-dimensional structure nozzle, and the ejection end of the three-dimensional structure nozzle is a three-dimensional special-shaped flow channel. The reduced-diameter flow rectifying pipe (2) is located in the middle section and is the liquid rectifying and speed-increasing device of the nozzle. It contains several strip-shaped rectifying fins (203) arranged circumferentially. The diversion elbow (1) is located at the incoming flow end and is the water inlet connector of the nozzle. The water outlet section of the diversion elbow (1) is designed as an elbow structure. The overall structure from the nozzle inlet to the nozzle outlet (301) of the three-dimensional special-shaped nozzle (3) is a cylindrical-cone coupling structure. The nozzle jet orifice of the nozzle outlet (301) is a three-dimensional duckbill special-shaped slotted structure. Along the flow direction of the jet orifice, V-shaped grooves are opened at the bottom and front of the midplane. The notch of the groove gradually opens outward and upward to mainly form a fan-shaped jet of the proximal range water body. Strip-shaped grooves are opened in the upper half of the midplane to mainly form a beam-shaped jet of the distal range water body. The interface between the V-shaped groove and the strip-shaped groove has a smooth transition, and they work together to promote the formation of a narrow-band range. After the fluid is ejected at a high speed in a narrow-band form from the three-dimensional special-shaped nozzle (3), a long strip-shaped narrow band (4) with uniform water volume distribution will be formed from near to far. By adjusting the flow rate, pressure, and elevation angle of the nozzle inlet, different ranges and different sprinkler irrigation intensities can be achieved.

2. The narrow-band spraying area jet nozzle for the field of farmland water-saving irrigation according to claim 1, characterized in that: The outer diameter and inner diameter of the large-diameter end of the reduced-diameter flow rectifying pipe (2) are 42 mm and 30 mm respectively, and the outer diameter and inner diameter of the small-diameter end are 27 mm and 20 mm respectively. Six strip-shaped rectifying fins (203) are arranged circumferentially at the front end of the pipe inner wall.

3. A narrow-band-shaped spraying area jet nozzle for the field of farmland water-saving irrigation according to claim 1, characterized in that: The reduced-diameter flow rectifying pipe (2) and the diversion elbow (1) adopt a single-end face plus gasket O-ring (201) sealing form, and 2 to 4 pre-tightening bolts (202) with self-pre-tightening force are arranged on the outer circle for connection.

4. A narrow-band-shaped spray field jet nozzle for the field of farmland water-saving irrigation according to claim 1, characterized in that: The three-dimensional special-shaped nozzle (3) and the reduced-diameter flow rectifying pipe (2) are directly connected by a positive or reverse thread (204) machined by matching turning. When installing, raw tape is wound inside or liquid sealant is applied to ensure the assembly coaxiality of the two.

5. A narrow-band spraying area jet nozzle for the field of farmland water-saving irrigation according to claim 1, characterized in that: Both the inner and outer surfaces of the water inlet (101) of the diversion elbow (1) are designed and processed with standard metric or imperial threads (102) to facilitate matching and connection with water inlet pipes of various specifications.

6. A narrow-band spraying area jet nozzle for the field of farmland water-saving irrigation according to claim 5, characterized in that: The outer diameter and inner diameter of the diversion elbow (1) are 40 mm and 30 mm respectively. The water outlet section of the diversion elbow is designed as an elbow structure to adjust the liquid flow coming vertically upward from the water inlet (101) to a direction with a small elevation angle to the horizontal. A boss for nozzle installation and positioning is machined in the middle section of the diversion elbow (1). The outer diameter of the boss is 50 mm and the width is 10 mm.

7. A narrow-band-shaped spraying area jet nozzle for the field of farmland water-saving irrigation according to claim 1, characterized in that: The said nozzle is used for fixed-point sprinkler irrigation, or the said nozzle is equipped on mobile sprinkler irrigation machines and irrigation units for performing farmland sprinkler irrigation on non-planting areas such as tractor roads and field roads.

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