CN105758613B - A kind of natural grains of sand emitter of controlled speed angle - Google Patents

Abstract

The invention provides a controllable speed and angle natural sand launch device, which includes a detachable shell, a rotatable iron ring, a "z"-shaped sand inlet pipe, a six-wing propeller, and a transmission bearing. The detachable shell is a flat cylinder Shape, the inner wall of the detachable shell is provided with an annular slideway, the circular slideway of the detachable shell is connected with a rotatable iron ring, the "z" shaped sand inlet pipe is fixed on the rotatable iron ring, and the detachable shell There is a strip-shaped slot and a sand-injecting port on the top, and one end of the "z"-shaped sand inlet pipe protrudes from the strip-shaped slot, and the "z"-shaped sand inlet pipe is moved to realize the rotation of the rotatable iron ring and " The z”-shaped sand inlet pipe can move within a limited range in the bar-shaped slot; the six-wing propeller is connected to the inner ring of the transmission bearing, and the launching device can launch sand particles with controllable speed and angle. High-speed photography and other instruments can study the particle bed collision process.

Description

A natural sand launch device with controllable speed and angle

technical field

The invention relates to a natural sand particle launching device with controllable speed and angle, which belongs to the technical field of machinery.

Background technique

The impact of wind and sand movement is everywhere, and its consequences have become one of the world's major environmental problems. Due to the massive deforestation of vegetation worldwide and the spread of wind and sand movement in desert areas, land desertification is becoming more and more serious. By 1998, about 900 million people and 100 countries had been affected by desertification. Even more frightening is that these figures are expected to double by 2025. At present, the total area of deserts in the world has reached 7 million square kilometers, and about 25% of the earth's land area has a certain degree of desertification. Every year, 41.5 million hectares of land in the world lose productive capacity. China is the hardest-hit area of desertification. The area of desert, Gobi and desertified land has accounted for about 27.64% of the country's land area. Not only that, but in the 1990s alone, the area of desertified land in my country expanded at a rate of about 2,460 square kilometers per year. . Due to the impact of the dry climate and the cutting of vegetation in the western region, some areas are now in an endlessly miserable scene. However, if it is just desertification, its impact is limited after all, but with desertification, there are many more serious hazards. In the western and central regions of China, large-scale wind and sand movements have continuously destroyed human houses, roads, and various railway facilities, and even many people died when disasters occurred. Even areas close to the coast are also devastated by large-scale sandstorms. More than once, we have seen the scene of wind and sand in the capital of Beijing on a certain day. We have seen the wind and sand sweeping from the western region to the east of the motherland more than once like a devil. Nowadays, the dust floating in the air has increasingly threatened our health, and we can see that the incidence of respiratory diseases has begun to rise. It is imperative to prevent and control desertification, desertification, and even large-scale sandstorm movement and sandstorm.

The wind and sand movement is mainly carried out by jumping. Due to the increase of wind speed, some surface sand particles are brought up. After these sand particles are accelerated by the wind in the air, they hit the surface sand particles and splash more sand particles. As more and more sand particles are splashed, the scale becomes larger and larger, eventually forming a large-scale wind and sand movement. In this process, the process of sand particles hitting the surface and rebounding and splashing other surface sand particles is a key step, which is called the particle-bed collision process in wind and sand physics. The particle-bed collision process is a key issue in the sand transition movement. Scholars commented that: the particle-bed collision analysis and its mechanical modeling are the core of the research work on the mechanism of sand movement, and it is the key to reveal the microscopic movement of sand particles and the macroscopic sand flow. The most critical step and the single most efficient way of linking movements.

Due to the small particle size (0.05-0.5mm) and irregular characteristics of sand particles, there is currently no device or instrument capable of launching sand particles at the scale of wind-sand flow in the experimental research of particle-bed collision in the world. Most of these experiments have used larger and more regular alternative materials such as glass beads, PVC materials, etc. However, the alternative materials are far from natural sand grains in terms of material, particle size, and shape, and as a result, natural sand grains cannot be applied at all. Due to the lack of devices or instruments capable of launching sand particles at the scale of aeolian sand flow, the work of directly measuring the natural particle-bed collision process and the jumping characteristics and distribution functions of sand particles has been stagnant for many years.

Contents of the invention

The present invention provides a natural sand particle launcher with controllable speed and angle, which can solve the above-mentioned problems, and can launch sand particles with controllable speed and angle, and can study the particle bed collision process by combining high-speed photography and other instruments.

In order to solve the above technical problems, the present invention provides the following technical solutions: a natural sand launcher with controllable speed and angle, including a detachable shell, a rotatable iron ring, a "z"-shaped sand inlet pipe, a six-wing propeller, and a transmission bearing , the detachable shell is oblate cylindrical, the inner wall of the detachable shell is provided with an annular slideway, the circular slideway of the detachable shell is connected with a rotatable iron ring, and the "z" shaped sand inlet pipe is fixed on the The rotatable iron ring, the detachable shell is provided with a strip-shaped slot and a sand injection port, one end of the "z"-shaped sand inlet pipe protrudes from the strip-shaped slot, and the "z"-shaped sand inlet pipe is moved , to realize the rotation of the rotatable iron ring and the movement of the "z"-shaped sand inlet pipe within a limited range in the bar-shaped slot; the six-wing propeller is connected to the inner ring of the transmission bearing, and the outer ring of the transmission bearing is connected to the detachable shell In the middle of the inner wall, the transmission shaft of the six-wing propeller is connected to the motor; the transmission bearing connects the propeller and the rotatable iron ring in series; the other end of the "z"-shaped sand inlet tube extends out of the edge of the rotation circle of the six-wing propeller ; Connect the two ends of the detachable shell to the cover to form a closed space.

Further, the detachable outer shell is composed of two semicircular shells, one end of the two semicircular shells is hingedly connected, and the other end is connected by a buckle movable connection method.

Further, the natural sand launching device includes a base, the upper surface of which is arc-shaped, just suitable for the outer circular surface of the detachable shell.

Further, the shape of the sand injection port is a long strip along the detachable shell, from the middle part to the middle and lower part of the detachable shell.

Further, the base is made of metal, and there are fixing devices on both sides of the top of the base, and the natural sand launching device is fixed by bolts.

Further, the direction of the sand injection port of the "z"-shaped sand inlet pipe is opposite to the rotation direction of the six-wing propeller.

Further, adjustment scales are provided on both sides of the notch of the bar-shaped card slot.

The natural sand particle launching device with controllable velocity and angle involved in the present invention can launch sand particles with controllable velocity and angle, and can study the particle bed collision process by combining high-speed photography and other instruments.

Description of drawings

Fig. 1 is the internal structure diagram of a kind of natural sand particle launching device of controllable velocity angle of the present invention;

Fig. 2 is a front view of a natural sand launching device with a controllable speed angle of the present invention;

Fig. 3 is a structure diagram of a detachable shell of a natural sand particle launcher with controllable speed and angle of the present invention;

Fig. 4 is a structure diagram of a detachable shell of a natural sand launcher with controllable speed and angle of the present invention;

Fig. 5 is a schematic diagram of the structure of a "z"-shaped sand inlet pipe of a natural sand particle launching device with a controllable speed and angle of the present invention;

Fig. 6 is a structural schematic diagram of a six-wing propeller of a controllable speed angle natural sand particle launching device of the present invention;

The markings in the figure are as follows: 1. Detachable shell; 2. Rotatable iron ring; 3. "Z" shaped sand inlet pipe; 4. Six-wing propeller; 5. Transmission bearing; 6. Base; 7. Strip slot ; 8. Buckle; 9. Hinge; 10. Ring slide; 11. Sand mouth.

detailed description

As shown in Figure 1, the natural sand particle launcher with controllable speed and angle includes a detachable shell 1, a rotatable iron ring 2, a "z"-shaped sand inlet pipe 3, a six-wing propeller 4, and a transmission bearing 5. The detachable The shell 1 is oblate cylindrical, and the inner wall of the detachable shell 1 is provided with 10 annular slideways, and the circular slideway of the detachable shell is connected with a rotatable iron ring, and the "z" shaped sand inlet pipe 3 is fixed on the detachable Turn the iron ring, the detachable shell is provided with a bar-shaped slot 7 and a sand injection port, one end of the "z"-shaped sand inlet pipe 3 protrudes from the bar-shaped slot, and the "z"-shaped sand inlet The tube 3 realizes the rotation of the rotatable iron ring 2 and the movement of the "z"-shaped sand inlet tube 3 within a limited range in the bar-shaped slot; the six-wing propeller is connected to the inner ring of the transmission bearing, and the outer ring of the transmission bearing is connected to the In the middle of the inner wall of the detachable shell, the transmission shaft of the six-wing propeller is connected to the motor; the transmission bearing connects the propeller and the rotatable iron ring in series; the other end of the "z"-shaped sand inlet pipe 3 extends to the six-wing propeller 4 outside the edge of the rotating circle.

The detachable shell is composed of two semicircular shells. One end of the two semicircular shells is hingedly connected, as shown in FIG.

The natural sand launching device includes a base 6, and the upper surface of the base is arc-shaped, which is just suitable for the outer circular surface of the detachable shell.

The sand injection port 11 is shaped as a strip along the detachable shell, from the middle part of the detachable shell to the middle and lower part.

Base 6 is made of metal, and both sides of the base top are provided with fixtures, and bolts are used to fix the natural sand launcher.

The sand-shooting port of the "z" shape sand inlet pipe 3 faces opposite to the direction of rotation of the six-wing propeller 4.

Adjustment scales are arranged on both sides of the notch of the bar-shaped card slot.

The experimental steps are as follows: connect the propeller and the rotatable iron ring in series through the transmission bearing; put the rotatable iron ring together with the propeller and the "z"-shaped sand inlet pipe into the slideway of the detachable shell, and adjust it to the angle required for the experiment:

(1) Turn on the motor, and put an appropriate amount of sand into the "z"-shaped sand inlet after the propeller speed is stable;

(2) The falling sand will be hit by the propeller, and the speed of the sand will increase after hitting, and some sand will fly out from the sand injection port, and finally impact on the bed;

(3) Adjusting the angle of the rotatable iron ring can change the angle of the sand particles flying out from the sand injection port, that is, the incident angle of the impact;

(4) Adjust the current intensity of the motor through the control terminal to adjust the motor speed, and finally change the incident speed of sand particles;

(5) Combined with high-speed photography and other means, the whole process of the impact of sand particles on the bed surface can be clearly observed.

The experimental results are as follows:

With the help of this instrument, 1024 grain-bed collision tests were carried out, and the behavior of natural sand grains in grain-bed collisions is far from that of substitute grains. Results include:

(1) Different from the experimental results of Djaoued Beladjine (07) using 6mm PVC material, the rebound angle of natural sand after particle-bed collision is closely related to the impact velocity and decreases linearly with the increase of impact velocity (their experiments show that both is irrelevant).

(2) Different from the results of Djaoued Beladjine (07), the ratio of rebound velocity to impact velocity is related to the impact velocity and increases linearly with the increase of impact velocity (its use shows that the two are independent). And Francois (2000)'s plastic disc (glass ball) experiment and Mark Gordon's (2011) glass ball-sand bed collision results are even opposite.

(3) The particle sputtering angle is related to the impact velocity and increases with the increase of the impact velocity.

(4) The number of splashed particles is related to the impact angle, and decreases with the increase of the impact angle.

(5) Of course, the experiment also confirmed many conclusions in previous experiments, such as: the rebound angle increases with the increase of the impact angle; the ratio of the rebound velocity to the impact velocity decreases with the increase of the impact angle; The sputtering angle increases with the increase of the impact angle; the number of splashed particles increases with the increase of the impact velocity.

(6) We grouped 1024 sets of data at the same time, calculated the average value, and gave the functional relationship of each microscopic physical quantity with the impact velocity and impact angle. At the same time, the form of the distribution function of each microphysics is given, such as: the rebound angle obeys the logarithmic normal distribution; the ratio of the rebound velocity to the impact velocity obeys the normal distribution, etc.

To sum up, the performance of natural sand particles in particle-bed collisions is more complex, and each microscopic physical quantity is often related to each parameter of the incident particle, and the interaction process has mutual influence and mutual coupling. It is not shown by regular, large particle size substitute materials, but only related to one of the parameters. Some qualitative relationships are even completely inconsistent. This is of great significance in helping to understand the interaction patterns of particles and bed surfaces.

There is no limit to the size of particles that can be emitted by the device, and it is not limited to emitting natural sand particles.

The specific implementation methods described in the present invention do not constitute a limitation to the scope of the application. Any modifications, equivalent replacements and improvements that can be made by professionals in the field within the spirit and principles of the present invention should be included in this application. within the scope of protection of the invention.

Claims (7)

1. A natural sand launcher with controllable speed and angle, characterized in that it includes a detachable shell, a rotatable iron ring, a "z" shape sand inlet pipe, a six-wing propeller, and a transmission bearing, and the detachable shell is Oblate cylindrical shape, the inner wall of the detachable shell is provided with a circular slideway, the circular slideway of the detachable shell is connected with a rotatable iron ring, the "z" shaped sand inlet pipe is fixed on the rotatable iron ring, the The detachable shell is provided with a bar-shaped slot and a sand injection port, and one end of the "z"-shaped sand inlet pipe protrudes from the strip-shaped slot, and the "z"-shaped sand inlet pipe is moved to realize the rotation of the rotatable iron ring. Rotation and movement of the "z"-shaped sand inlet pipe within a limited range in the bar-shaped slot; the six-wing propeller is connected to the inner ring of the transmission bearing, and the outer ring of the transmission bearing is connected to the middle part of the inner wall of the detachable shell. The transmission shaft of the wing propeller is connected to the motor; the transmission bearing connects the propeller and the rotatable iron ring in series; the other end of the "z"-shaped sand inlet pipe extends beyond the edge of the rotating circle of the six-wing propeller; the two sides of the detachable shell A closed space is formed after the ends are connected to the cover. 2. A kind of natural sand launcher with controllable speed and angle according to claim 1, characterized in that, the detachable shell is made up of two semicircular shells, one end of the two semicircular shells is hingedly connected, and the other end adopts The buckle activity connection method is connected. 3. A natural sand launcher with controllable speed and angle according to claim 1, characterized in that the natural sand launcher includes a base, the upper surface of which is arc-shaped, just suitable for detachable The outer circular surface of the shell. 4. A natural sand launch device with controllable speed and angle according to claim 1, characterized in that, the shape of the sand injection port is a long strip along the detachable shell, from the middle of the detachable shell Along to the lower middle. 5. The natural sand launcher with controllable speed and angle according to claim 1 or 3, characterized in that, the material of the base is metal, and fixing devices are arranged on both sides of the top of the base, and bolts are used to push the natural sand The launcher is fixed. 6. A natural sand particle launching device with controllable speed and angle according to claim 1, characterized in that, the direction of the sand injection port of the "z" shaped sand inlet pipe is opposite to the direction of rotation of the six-wing propeller. 7. The natural sand launcher with controllable speed and angle according to claim 1, characterized in that adjustment scales are provided on both sides of the notch of the bar-shaped slot.