CN114307899A

CN114307899A - Rotational flow pulse cavitation device

Info

Publication number: CN114307899A
Application number: CN202111644057.1A
Authority: CN
Inventors: 苟如意; 康晨晨; 罗训; 叶鑫; 钟思鹏
Original assignee: Southwest Petroleum University
Current assignee: Southwest Petroleum University
Priority date: 2021-12-30
Filing date: 2021-12-30
Publication date: 2022-04-12
Anticipated expiration: 2041-12-30
Also published as: CN114307899B

Abstract

The invention relates to a rotational flow pulse cavitation device which comprises a spiral flow guide section, a hollow spiral flow guide section, an air inlet cavity, a self-vibration cavitation cavity and a diffusion pipe. The spiral flow guide section and the hollow spiral flow guide section have the rotational flow blade angle of 30-50 degrees, and the spiral flow guide section is positioned below the hollow spiral flow guide section; the hollow spiral diversion section is provided with a hollow channel at the axis center, and the upper part of the hollow spiral diversion section is connected with the air inlet cavity; the wall surface of the air inlet cavity is provided with an air inlet; the upper part of the air inlet cavity is connected with the self-vibration cavitation cavity; a tangential suction inlet is formed in the cavity wall of the self-vibration cavitation cavity, and a guide plate is arranged at the tangential suction inlet; the tangential included angle of the guide plate is 10-20 degrees; the lower end of the diffusion pipe is connected with the upper end of the self-vibration cavitation cavity. The invention has simple structure and high efficiency, can form strong spiral flow from the conventional fluid, can generate gas-liquid separation under the action of centrifugal force, is beneficial to improving the flow speed by split-phase flow, more effectively promotes the generation of cavitation bubbles in the self-vibration cavitation cavity, and accelerates the ejection of the formed cavitation bubbles, thereby further improving the cavitation efficiency.

Description

Rotational flow pulse cavitation device

Technical Field

The invention belongs to the technical field of hydrodynamic cavitation, and particularly relates to a rotational flow pulse cavitation device which is suitable for oil field drilling exploitation.

Background

Hydrodynamic cavitation is the effect of gas molecular motion on a liquid, which, upon impact of gas into the liquid, results in a mass of gas-phase microbubbles called "gas nuclei" in suspension in the liquid. When the pressure in the liquid drops below the separation pressure of air, these gas nuclei dissolved in the liquid are rapidly separated therefrom to generate a large number of bubbles. When these gases enter the high pressure zone with the liquid flow, the liquid particles move to the center of the cavity at high speed with the collapse of the bubbles to generate strong impact, and the instantaneous local pressure rises sharply, which is called cavitation effect. Since this phenomenon has been discovered, the industrial field is basically plagued by the negative effects of cavitation, and therefore, people are always looking for how to make this effect positive for people to use, and move to the industrial field by using the energy brought by cavitation. Nowadays, the cavitation effect is widely applied to various industrial fields, such as petrochemical industry, shale exploitation, industrial cleaning and the like, and various cavitation generating devices are provided.

With the intensive research on cavitation technology, the applied field is more extensive, and the structural style of the cavitation device is various, however, how to improve the cavitation effect by using a simple structure, and how to increase the cavitation energy and the generation of cavitation bubbles are the key points of research.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides the rotational flow pulse cavitation device which is simple in structure, high in efficiency and capable of improving cavitation bubble generation and cavitation efficiency.

The technical scheme of the invention is as follows:

a rotational flow pulse cavitation device comprises a spiral flow guide section, a hollow spiral flow guide section, an air inlet cavity, a self-vibration cavitation cavity and a diffusion pipe. The spiral flow guide section and the hollow spiral flow guide section have the rotational flow blade angle of 30-50 degrees, and the spiral flow guide section is positioned below the hollow spiral flow guide section; the hollow spiral diversion section is provided with a hollow channel at the axis center, and the upper part of the hollow spiral diversion section is connected with the air inlet cavity; the wall surface of the air inlet cavity is provided with an air inlet, and the upper part of the air inlet cavity is connected with the self-vibration cavitation cavity; a tangential suction inlet is formed in the wall surface of the self-vibration cavitation cavity, and a guide plate is arranged at the suction inlet; the tangential included angle of the guide plate is 10-20 degrees; the lower end of the diffusion pipe is connected with the upper end of the vibration cavity.

The rotational flow pulse cavitation generating device has the following action mechanism:

s1: after entering the spiral flow guide section under certain pressure, the fluid forms spiral flow under the action of a 40-degree rotational flow blade, and the spiral flow is subjected to gas-liquid separation for the first time under the action of centrifugal force in the rising process;

s2: after the spiral fluid generates gas-liquid separation, a liquid phase moves along the wall surface of the shaft, a gas phase moves along the center of the shaft, and the gas phase fluid ascending along the center of the shaft enters the self-vibration cavitation cavity after passing through the hollow channel and the gas inlet cavity of the hollow spiral flow guide section;

s3: the liquid phase rising along the wall surface of the well barrel is subjected to gas-liquid separation again through the 40-degree swirl vanes of the hollow spiral diversion section, the liquid phase continues to rise along the wall surface of the well barrel, and the gas phase enters the self-vibration cavitation cavity through the gas inlet cavity;

and S4, enabling the high-speed ascending air flow to enter a self-vibration cavitation cavity to form high-speed shearing air flow. The self-oscillation cavitation cavity wall is provided with a tangential suction inlet, high-speed airflow passes through the self-oscillation cavitation cavity, negative pressure is generated in the cavity, a liquid phase along the wall surface of the well casing is sucked into the self-oscillation cavitation cavity in a tangential manner under the action of a 15-degree guide plate after passing through the suction inlet, the liquid phase rotating in a tangential manner generates a cavitation effect in the cavity under the action of high-speed shear airflow, more cavitation bubbles are generated more easily, the self-oscillation cavitation cavity can change continuous jet flow into pulse jet flow, and then the generated cavitation bubbles are sprayed out through a diffusion pipe in an accelerated manner, so that the fluid speed is further improved, and the cavitation effect is improved.

Compared with the prior art, the invention has the following advantages:

1. through the structural design of the double-spiral section, the conventional fluid forms strong spiral flow, the strong spiral fluid generates gas-liquid separation under the action of centrifugal force, split-phase flow is beneficial to improving the flow speed, and high-speed gas flow is more beneficial to generating cavitation bubbles.

2. The wall of the self-vibration cavitation cavity is provided with a tangential suction inlet and a guide plate, after high-speed airflow passes through the self-vibration cavitation cavity, negative pressure is generated in the cavity, a liquid phase along the wall surface is sucked into the self-vibration cavitation cavity through the suction inlet after passing through the guide plate, and a large amount of cavitation bubbles are generated in the cavity more easily by the liquid phase fluid in tangential motion under the shearing action of the high-speed airflow.

3. The self-vibration cavitation cavity changes continuous jet flow into pulse jet flow, and further improves the cavitation speed and the generation of cavitation bubbles. The external-suction self-vibration cavitation cavity is beneficial to forming cavitation bubbles and improving the cavitation efficiency, thereby further improving the cavitation efficiency.

4. The invention has simple structure, low cost and wider application range.

Drawings

FIG. 1 is a schematic diagram of a half-section structure of a swirling flow pulse cavitation device according to the present invention;

FIG. 2 is a schematic structural view of the self-oscillating cavitation chamber of the present invention;

FIG. 3 is a schematic sectional view taken along line A-A of FIG. 2;

wherein, 1, spiral diversion section; 2. a hollow spiral flow guide section; 3. an air inlet cavity; 4. a self-vibrating cavitation chamber; 401 a baffle; 5. a diffuser tube.

Detailed Description

The following detailed description of the present invention will be made with reference to the accompanying drawings, but the present invention is not limited to the embodiments.

As shown in fig. 1, 2 and 3, the rotational flow pulse cavitation device of the present invention has the following action mechanism:

1: after entering the spiral flow guide section 1 under a certain pressure, the fluid forms spiral flow under the action of a 40-degree rotational flow blade, and the spiral flow is subjected to gas-liquid separation for the first time under the action of centrifugal force in the rising process; 2: after the spiral fluid generates gas-liquid separation, a liquid phase moves along the wall surface of the shaft, a gas phase moves along the center of the shaft, and the gas phase fluid ascending along the center of the shaft enters a self-vibration cavitation cavity 4 after passing through a hollow channel of the hollow spiral flow guide section 2 and the gas inlet cavity 3; 3: the liquid phase rising along the wall surface of the well barrel is subjected to gas-liquid separation again through the 40-degree rotational flow blades of the hollow spiral flow guide section 2, the liquid phase continues to rise along the wall surface of the well barrel, and the gas phase enters the self-vibration cavitation cavity 4 through the gas inlet cavity 3; 4: the high-speed ascending air flow enters the self-vibration cavitation cavity 4 to form high-speed shearing air flow. The cavity wall of self-oscillation cavitation chamber 4 is opened has the tangential sunction inlet, high-speed air current is behind self-oscillation cavitation chamber 4, the intracavity produces the negative pressure, liquid phase along the well casing wall passes through behind the sunction inlet and is inhaled in self-oscillation cavitation chamber 4 by the tangential under the effect of 15 guide plates 401, the rotatory liquid phase fluid of tangential produces cavitation effect in the cavity under the high-speed shear airflow effect, produce more cavitation bubbles more easily, self-oscillation cavitation chamber 4 can become the pulse jet with continuous jet, and then pass through diffuser 5 with the cavitation bubble that produces and spout with higher speed, further improve fluid velocity, thereby cavitation effect has been improved.

Claims

1. A rotational flow pulse cavitation device is characterized in that the tool mainly comprises a spiral flow guide section (1), a hollow spiral flow guide section (2), an air inlet cavity (3), a self-vibration cavitation cavity (4) and a diffusion pipe (5), wherein the angle of rotational flow blades of the spiral flow guide section (1) and the hollow spiral flow guide section (2) is 30-50 degrees, and the spiral flow guide section (1) is positioned below the hollow spiral flow guide section (2); the axis of the hollow spiral flow guide section (2) is provided with a hollow channel, and the upper part of the hollow spiral flow guide section (2) is connected with the air inlet cavity (3); an air inlet is formed in the wall surface of the air inlet cavity (3), and the upper part of the air inlet cavity (3) is connected with the self-vibration cavitation cavity (4); a tangential suction inlet is formed in the wall of the self-vibration cavitation cavity (4), and a guide plate (401) is arranged at the tangential suction inlet; the tangential included angle of the guide plate (401) is 10-20 degrees; the lower end of the diffusion pipe (5) is connected with the upper end of the self-vibration cavitation cavity (4).