阅读说明：本技术 一种有自混流作用的喷嘴 (Nozzle with self-mixing flow function ) 是由 曹秀荣 张泽安 张振华 李春萍 王飞 崔昆 于 2019-11-08 设计创作，主要内容包括：本发明涉及一种有自混流作用的喷嘴,属于射流技术领域。本发明综合运用了后混引射式混流和自激振荡脉冲射流的原理；采用后混合式磨料喷嘴喷出的磨料射流减少了输运管壁得磨蚀时间,射流沿程损失小,不易堆积,可防止管道堵塞；同时运用自激振荡脉冲的射流形式,使变压特性和空化的作用增强,大大提高了工作效率。结构合理而紧凑,使用方便。(The invention relates to a nozzle with self-mixing flow function, belonging to the technical field of jet flow. The invention comprehensively utilizes the principle of post-mixing injection type mixed flow and self-oscillation pulse jet; the abrasive jet flow sprayed out by the post-mixing abrasive nozzle reduces the abrasion time of the conveying pipe wall, has small loss along the way of the jet flow, is not easy to accumulate, and can prevent the pipeline from being blocked; meanwhile, the jet form of the self-excited oscillation pulse is utilized, so that the transformation characteristic and the cavitation effect are enhanced, and the working efficiency is greatly improved. Reasonable and compact structure and convenient use.)

1. A nozzle with self-mixing flow function is characterized by comprising a high-pressure water nozzle (1), a sand inlet pipe (2), a mixing oscillation part and a focusing pipe (4), wherein the center of the mixing oscillation part is provided with a cavity, namely a mixing oscillation cavity (3);

high-pressure water is firstly injected into a mixing oscillation cavity (3) of a nozzle with self-mixing flow through a high-pressure water nozzle (1), abrasive is sucked into the mixing oscillation cavity (3) from a sand inlet pipe (2) by adopting a post-mixing injection type mixing principle, then the high-pressure water and the abrasive are mixed and accelerated in the mixing oscillation cavity (3) by utilizing a self-excitation oscillation principle, and then abrasive jet flow is sprayed out from a focusing pipe (4).

2. The nozzle according to claim 1, characterized in that the high-pressure water nozzle (1), the sand inlet pipe (2) and the focusing pipe (4) are arranged on the mixing oscillation section; the high-pressure water nozzles (1) and the focusing pipes (4) are respectively arranged at the left side and the right side of the mixing oscillation part, and the sand inlet pipes (2) are axially symmetrically arranged around the high-pressure water nozzles (1), so that water and abrasive mixed flow vortex rings in the mixing oscillation cavity (3) are symmetrically and uniformly distributed.

3. A nozzle according to claim 2, characterized in that the sand inlet pipes (2) are arranged at an angle of 60 degrees to the axial direction of the high-pressure water nozzle (1) on both sides of the high-pressure water nozzle (1), and the centre of each sand inlet pipe (2) is at a radial distance of 7.5mm from the centre of the high-pressure water nozzle (1).

4. A nozzle according to claim 3, characterized in that the length of the mixing oscillation chamber (3) is determined according to the size of the high pressure water nozzle (1), the length-diameter ratio of the mixing oscillation chamber (3) is 0.5, and the ratio of the length of the mixing oscillation chamber (3) to the diameter of the high pressure water nozzle (1) is 2.2-7.8.

5. Nozzle according to claim 4, characterized in that the ratio of the length of the oscillating mixing chamber (3) to the diameter of the high-pressure water nozzle (1) is 6.25.

6. The nozzle according to claim 5, characterized in that the diameter of the high-pressure water nozzle (1) is calculated and derived from Bernoulli equation and continuity equation, the diameter of the focusing tube (4) is determined according to the high-pressure water nozzle (1), the diameter ratio of the focusing tube (4) to the high-pressure water nozzle (1) is 1.5-2.3 times and more than 3 times of the abrasive grain diameter, and the diameter of the focusing tube (4) is 8 mm.

7. Nozzle according to claim 6, characterized in that the ratio of the diameter of the entire self-mixing nozzle to the high-pressure water nozzle (1) is 4.

8. Nozzle according to claim 7, characterized in that the connection side of the mixing oscillation section to the focusing tube (4) is provided with a concave cone angle.

9. A nozzle according to claim 8, characterized in that the mixing oscillation chamber (3) has a cone angle in the range of 110 ° to 130 °.

10. A nozzle according to claim 9, characterized in that the mixing oscillation chamber (3) has a cone angle of 120 °.

Technical Field

The invention belongs to the technical field of jet flow, and particularly relates to a nozzle with a self-mixing flow function.

Background

The abrasive jet is a liquid-solid two-phase medium jet formed by mixing abrasive and high-speed flowing water or high-pressure water, and is the abrasive jet which is the most widely applied at present; the abrasive nozzle is the key for forming abrasive jet flow, and the abrasive nozzle is divided into a front mixing type and a rear mixing type according to the mixing mode of the abrasive nozzle; the abrasive jet flow sprayed out of the front mixing type abrasive nozzle has long abrasion time on the conveying pipe wall, the loss of the jet flow along the way is large, and the abrasive is easy to accumulate in the front mixing chamber, so that the pipeline is blocked; then, the mixed abrasive nozzle has a poor effect because the water and the abrasive in the mixing chamber are not sufficiently mixed and the mixed fluid is not sufficiently accelerated.

In order to improve the erosion capacity of the jet flow, namely improve the working efficiency of jet flow crushing, cleaning and cutting, at present, research on new jet flow devices and processes is mainly dedicated at home and abroad; some jet flows such as cavitation jet flow, front mixed abrasive jet flow, rear mixed abrasive jet flow, intermittent jet flow, pulse jet flow and the like play great roles in the aspects of cutting, rust removal, petroleum drilling and the like; but the transformation characteristic and the cavitation are poor, and the working efficiency is low.

Disclosure of Invention

Technical problem to be solved

The technical problem to be solved by the invention is as follows: the problems that the abrasive jet flow sprayed out from the front mixed abrasive nozzle has long abrasion time on the wall of a conveying pipe, the loss of the jet flow along the way is large, the abrasive is easy to accumulate in a front mixing chamber, the pipeline is blocked and the like are effectively solved; but also solves the mixing and accelerating problems of the post-mixed abrasive and water; meanwhile, the problems of poor transformation characteristic and cavitation and low working efficiency are solved.

(II) technical scheme

In order to solve the technical problem, the invention provides a nozzle with self-mixing flow function, which comprises a high-pressure water nozzle 1, a sand inlet pipe 2, a mixing oscillation part and a focusing pipe 4, wherein the center of the mixing oscillation part is provided with a cavity, namely a mixing oscillation cavity 3;

high-pressure water is firstly injected into a mixing oscillation cavity 3 of a nozzle with self-mixing flow through a high-pressure water nozzle 1, abrasive is sucked into the mixing oscillation cavity 3 from a sand inlet pipe 2 by adopting a post-mixing injection type mixing principle, then the high-pressure water and the abrasive are mixed and accelerated in the mixing oscillation cavity 3 by utilizing a self-excitation oscillation principle, and then abrasive jet flow is ejected from a focusing pipe 4.

Preferably, the high-pressure water nozzle 1, the sand inlet pipe 2 and the focusing pipe 4 are all arranged on the mixing and oscillating part; the high-pressure water nozzles 1 and the focusing pipes 4 are respectively arranged at the left side and the right side of the mixing oscillation part, and the sand inlet pipes 2 are axially symmetrically arranged around the high-pressure water nozzles 1, so that water and abrasive mixed-flow vortex rings in the mixing oscillation cavity 3 are symmetrically and uniformly distributed.

Preferably, the sand inlet pipes 2 and the high-pressure water nozzles 1 form an included angle of 60 degrees in the axial direction and are arranged on two sides of the high-pressure water nozzles 1, and the radial distance from the center of each sand inlet pipe 2 to the center of the high-pressure water nozzle 1 is 7.5 mm.

Preferably, the length of the mixing oscillation cavity 3 is determined according to the size of the high-pressure water nozzle 1, the length-diameter ratio of the mixing oscillation cavity 3 is 0.5, and the diameter ratio of the length of the mixing oscillation cavity 3 to the high-pressure water nozzle 1 is 2.2-7.8.

Preferably, the ratio of the length of the oscillating mixing chamber 3 to the diameter of the high pressure water nozzle 1 is 6.25.

Preferably, the diameter of the high-pressure water nozzle 1 is calculated and derived from a Bernoulli equation and a continuity equation, the diameter of the focusing tube 4 is determined according to the high-pressure water nozzle 1, the diameter ratio of the focusing tube 4 to the high-pressure water nozzle 1 is 1.5-2.3 times, and is more than 3 times of the abrasive grain diameter, and the diameter of the focusing tube 4 is 8 mm.

Preferably, the diameter ratio of the whole self-mixing nozzle to the high-pressure water nozzle 1 is 4.

Preferably, the connection side of the hybrid oscillating portion and the focusing tube 4 is provided with a concave taper angle.

Preferably, for the cone angle design of the mixing oscillation chamber 3, the cone angle of the mixing oscillation chamber 3 ranges from 110 ° to 130 °.

Preferably, the mixing oscillation chamber 3 has a cone angle of 120 °.

(III) advantageous effects

The invention comprehensively utilizes the principle of post-mixing injection type mixed flow and self-oscillation pulse jet; the abrasive jet flow sprayed out by the post-mixing abrasive nozzle reduces the abrasion time of the conveying pipe wall, has small loss along the way of the jet flow, is not easy to accumulate, and can prevent the pipeline from being blocked; meanwhile, the jet form of the self-excited oscillation pulse is utilized, so that the transformation characteristic and the cavitation effect are enhanced, and the working efficiency is greatly improved. Reasonable and compact structure and convenient use.

Drawings

FIG. 1 is a schematic view of the overall structure of a nozzle with a flow mixing function according to the present invention;

FIG. 2 is a front cross-sectional view of a nozzle of the present invention;

FIG. 3 is an exploded view of the nozzle of the present invention;

FIG. 4 is a cloud of the internal flow field pressures of the nozzle of the present invention;

FIG. 5 is a cloud of the internal flow field velocities of the nozzle of the present invention;

FIG. 6 is a cloud of the turbulent energy field inside the nozzle of the present invention;

fig. 7 is a cloud of the volume fraction of water inside the nozzle of the present invention.

Wherein: 1. high-pressure water nozzle, 2, sand inlet pipe, 3, mixing oscillation cavity, 4 and focusing pipe.

Detailed Description

In order to make the objects, contents, and advantages of the present invention clearer, the following detailed description of the embodiments of the present invention will be made in conjunction with the accompanying drawings and examples.

The invention provides a nozzle with self-mixing flow function, which integrates post-mixing injection type and self-excited oscillation pulse, can fully mix abrasive and water, fully accelerate fluid after solid-liquid two-phase flow mixing, and has longer service life.

As shown in figures 1 to 3, the invention provides a nozzle with self-mixing function, which integrates post-mixing type and self-excited oscillation pulses, and comprises a high-pressure water nozzle 1, a sand inlet pipe 2, a mixing oscillation part and a focusing pipe 4, wherein the center of the mixing oscillation part is provided with a cavity, namely a mixing oscillation cavity 3.

The invention is designed and realized by adopting the rear mixing injection type mixing principle and the self-excited oscillation principle. High-pressure water is firstly injected into a mixing oscillation cavity 3 of a nozzle with self-mixing flow through a high-pressure water nozzle 1, abrasive is sucked into the mixing oscillation cavity 3 from a sand inlet pipe 2 by adopting a post-mixing injection type mixing principle, then the high-pressure water and the abrasive are mixed and accelerated in the mixing oscillation cavity 3 by utilizing a self-excitation oscillation principle, and then abrasive jet flow is ejected from a focusing pipe 4.

The high-pressure water nozzle 1, the sand inlet pipe 2 and the focusing pipe 4 are all arranged on the mixing oscillation part; the high-pressure water nozzles 1 and the focusing pipes 4 are respectively arranged at the left side and the right side of the mixing oscillation part, and the sand inlet pipes 2 are axially symmetrically arranged around the high-pressure water nozzles 1, so that water and an abrasive mixed-flow vortex ring in the mixing oscillation cavity 3 are symmetrically and uniformly distributed, and the abrasive is promoted to be more uniformly mixed in the mixing oscillation cavity 3; the sand inlet pipes 2 and the high-pressure water nozzles 1 are axially arranged at 60-degree included angles, the sand inlet pipes 2 are axially arranged at 60-degree included angles on two sides of the high-pressure water nozzles 1, the radial distance between the center of each sand inlet pipe 2 and the center of the high-pressure water nozzle 1 is 7.5mm, and the arrangement can ensure that water and abrasive mixed flow vortex rings in the cavity are symmetrically and uniformly distributed, so that the abrasive is more uniformly mixed in the oscillation cavity;

for the design of the mixed oscillation cavity, when the length-diameter ratio of the self-excited oscillation cavity is about 1.2-1.8 under the general condition, the mixing effect and the accelerating effect in the cavity are better. However, in the invention, the sand pipe 2 is added on the self-oscillation cavity, so the length-diameter ratio of the sand pipe is changed, and the research shows that when the length-diameter ratio of the mixing oscillation cavity 3 is 0.5, the mixing effect and the accelerating effect in the cavity are best, so the length-diameter ratio of the mixing oscillation cavity 3 is designed to be 0.5. The length of the mixing oscillation cavity 3 can be determined according to the size of the high-pressure water nozzle 1, when the diameter ratio of the length of the mixing oscillation cavity 3 to the high-pressure water nozzle 1 is 2.2-7.8, the effect of the mixing oscillation cavity 3 is better, and the diameter ratio of the length of the mixing oscillation cavity 3 to the high-pressure water nozzle 1 is 6.25, so that the mixing and accelerating effect in the cavity is optimal.

The diameter of the high-pressure water nozzle 1 can be computationally derived from the bernoulli equation and the continuity equation. The diameter of the focusing tube 4 is determined according to the high-pressure water nozzle 1, the diameter ratio of the focusing tube 4 to the high-pressure water nozzle 1 is preferably 1.5-2.3 times, but more than 3 times of the abrasive grain diameter, and finally when the diameter d2 of the focusing tube 4 is determined to be 8mm, the mixing effect and the accelerating effect in the nozzle with the self-mixing effect are better, and when the diameter ratio of the nozzle with the self-mixing effect to the high-pressure water nozzle 1 is 4, the effect in the nozzle with the self-mixing effect is best.

The connection side of the mixed oscillation part and the focusing tube 4 is provided with an inward-concave cone angle; for the cone angle design of the mixing and oscillating chamber 3, the mixing effect and the acceleration effect in the chamber are better when the cone angle range of the oscillating and mixing chamber 3 is 110-130 degrees, the effect is the best when the cone angle is 120 degrees, and the manufacture is more convenient than other angles, so in the invention, the cone angle of the oscillating and mixing chamber 3 is 120 degrees.

The working principle of the invention is as follows: high-pressure water from the high-pressure pump is accelerated into the mixing oscillation cavity 3 through the high-pressure water nozzle 1, so that a beam of high-speed jet flow is generated, when the beam of jet flow passes through the mixing oscillation cavity 3, the mixing oscillation cavity 3 locally generates negative pressure due to the Venturi effect, abrasive materials are sucked from the sand inlet pipe 2, the abrasive materials are contacted with the high-speed jet flow in the mixing oscillation cavity 3, mixed and moved together, and a high-speed abrasive water jet is formed and is sprayed out from the focusing pipe 4. The energy exchange and acceleration effects of the abrasive in the pulse jet state are superior to those of the common abrasive jet, the abrasive pulsates along with water (the speeds of the abrasive and the water are different) and obtains a speed higher than that of the jet from the high-pressure water nozzle, so that the specific energy consumption of the jet is reduced, and the erosion effect of the jet is improved.

It can be seen that the invention adopts the principle of back mixing injection type mixing and the principle of self-excited oscillation. High-pressure water is firstly injected into an oscillating cavity 3 of the mixer through a nozzle 1, abrasive is sucked into the mixing oscillating cavity 3 from a sand inlet pipe 2 by adopting a post-mixing injection type mixing principle, and then the high-pressure water and the abrasive are mixed and accelerated in the mixing oscillating cavity 3 by utilizing a self-oscillation principle. This novel flow mixer is not earlier with water and abrasive material well mixed back, rethread nozzle jets into the oscillation intracavity and accelerates, but directly set up two on mixing oscillation cavity 3 and go into sand pipe 2, make high pressure water and abrasive material intensive mixing and accelerate in mixing oscillation cavity 3, the mixing of this kind of mode abrasive material and water is behind high pressure water jet, this has just avoided the wearing and tearing of high pressure abrasive water jet to high pressure nozzle, and the principle of the fluidic of self-excited oscillation pulse has been utilized, abrasive material and high pressure water are in mixing oscillation intracavity intensive acceleration and mixing, can reduce the pressure of pump and not influence fluidic effect like this in certain extent, thereby can provide the life of high-pressure pump and water jet, the cost is reduced. The invention also applies the mixing principle of post-mixing injection type, thus avoiding the problems of abrasive accumulation, pipeline blockage, longer on-way abrasion and the like caused by pre-mixing.

The abrasive inlet is directly arranged on the mixed oscillation cavity, the abrasive does not enter the mixed oscillation cavity through the high-pressure water nozzle, but enters the mixed oscillation cavity through the abrasive inlet arranged on the mixed oscillation cavity, and is mixed and accelerated in the cavity, so that the structure is exquisite, simplified and easier to process while the nozzle is prevented from being abraded by the abrasive.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.