CN113369029B - Injection type low-pressure super-distance gas acceleration spray head - Google Patents

Abstract

The invention discloses an injection type low-pressure over-distance gas accelerating nozzle, wherein an ultrasonic nozzle is arranged in an injector to form an ultrasonic accelerating flow channel and a contraction accelerating channel, and the structures of the injector and the ultrasonic nozzle are designed and the structural parameters are optimized, so that the contraction accelerating channel can inject gas flow in the ultrasonic nozzle. The air flow is divided into two paths after being rectified by the rectifying air storage chamber, and a low-pressure environment is formed at the outlet of the supersonic nozzle after one path is accelerated by the contraction accelerating channel; one path is accelerated to supersonic speed through a supersonic nozzle. According to the invention, the injection distance of the spray head is effectively increased by an injection mode, and the requirement on the air source pressure is greatly reduced.

Description

A jet-type low-pressure super-distance gas acceleration nozzle

technical field

The invention relates to a gas acceleration nozzle, in particular to an injection type low-pressure ultra-distance gas acceleration nozzle.

Background technique

Gas acceleration nozzles are widely used in industrial and agricultural fields such as metallurgy, energy, materials and chemicals. For example, in metallurgical technology, oxygen forms a high Mach number oxygen jet through the nozzle and then impacts the molten pool. The impact distance has an important impact on the stirring effect of molten steel at the bottom of the molten pool; in the mineral field, gas acceleration nozzles are required to achieve rapid air exchange. At the same time, the efficient purification of dust can be achieved with the help of high-speed airflow. The pressure of the nozzle air source directly affects the spray distance, gas cost and production safety. Therefore be badly in need of a kind of nozzle that spray distance is big and air source pressure is low.

At present, there are mainly two types of gas acceleration nozzles: one is a contraction nozzle, and the other is a Laval nozzle that shrinks first and then expands. The Mach number at the exit of the nozzle determines the injection distance of the gas jet. For the shrinking nozzle, the acceleration of the airflow can be realized, but it can only be accelerated to Mach number 1, and the acceleration range is limited; for the Laval nozzle, in principle, this type of nozzle can form a wide range of Mach number airflow, but with the Mach number The increase of the number requires a linear increase in the air source pressure. When the Mach number is 2.0, the required air source pressure is 16atm; when the Mach number is 3.0, the required air source pressure is 35atm, so when it is necessary to obtain a larger spray distance, a larger spray speed is required, resulting in a greatly increased gas consumption. At the same time, security risks are increased.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the above-mentioned defects, and provide an ejector-type low-pressure over-distance gas acceleration nozzle. By arranging a supersonic nozzle in the ejector, an ultrasonic acceleration flow channel and a contraction acceleration channel are formed. At the same time, the ejector and the supersonic The structure of the nozzle is optimized and the structural parameters are optimized so that the shrinkage acceleration channel ejects the gas flow in the supersonic nozzle, and a gas acceleration nozzle with low gas source pressure, high outlet Mach number range and large gas jet distance is obtained. The accelerated nozzle adopts the injection method to realize the ultra-distance injection under the lower air source pressure.

In order to realize the foregoing invention object, the present invention provides following technical scheme:

An injection type low-pressure ultra-distance gas acceleration nozzle, characterized in that it includes a rectification gas storage chamber, a supersonic nozzle and an ejector;

The ejector is a hollow circular platform structure, and the supersonic nozzle is set inside the ejector; the supersonic nozzle is a cylindrical structure with an ultrasonic acceleration flow channel inside, and a contraction acceleration channel is formed between the supersonic nozzle and the ejector; the supersonic nozzle and the ejector Connect with the rectification air storage chamber;

The gas enters the supersonic acceleration flow channel and the contraction acceleration channel respectively from the rectification gas storage chamber, the gas ejected through the contraction acceleration channel forms a low pressure at the outlet of the supersonic nozzle, and the gas injected into the supersonic acceleration channel is ejected at supersonic speed.

Further, the supersonic acceleration channel is a Laval channel.

Further, the axes of the supersonic nozzle and the ejector coincide; the supersonic nozzle is fixed inside the ejector through a connecting rod; the two ends of the connecting rod are respectively connected to the supersonic nozzle and the ejector, and along the ejector Evenly distributed in the circumferential direction; there are 6 connecting rods.

Further, the ratio of the gas pressure in the rectified gas storage chamber to the atmospheric pressure is 1.89-7:1.

Further, the Mach number at the outlet of the contraction acceleration channel is 0.2-1; the Mach number at the outlet of the supersonic nozzle is 1.5-4.0.

Further, the ratio of the ejector inlet diameter Φa to the outlet diameter Φe is 2.5-4:1.

Further, the ratio of the supersonic nozzle inlet diameter Φb to the supersonic nozzle outlet diameter Φd is 1.25˜1.42:1.

Further, the ratio of the ejector inlet diameter Φa to the supersonic nozzle inlet diameter Φb is 1.1-1.2:1; the ratio of the supersonic nozzle outlet diameter Φd to the throat diameter Φc of the supersonic acceleration channel is 1.1-11:1.

Further, the ratio of the height L1 of the rectified gas storage chamber to the total height L2 of the gas acceleration nozzle is 0.2˜0.3:1.

Further, the inlet end of the ejector is flush with the inlet end of the supersonic nozzle; the height of the supersonic nozzle is smaller than that of the ejector.

Compared with the prior art, the present invention has the following beneficial effects:

(1) An ejection type low-pressure ultra-distance gas acceleration nozzle of the present invention, by setting a supersonic nozzle in the ejector, an ultrasonic acceleration flow channel and a contraction acceleration channel are formed, so that the contraction acceleration channel ejects the airflow in the supersonic nozzle , to obtain a gas acceleration nozzle with low gas source pressure, high outlet Mach number range, and large gas jet distance, and the ejection method is used to reduce the pressure at the outlet of the nozzle;

(2) A kind of injection type low-pressure ultra-distance gas acceleration nozzle of the present invention has designed the structure of the ejector and the supersonic nozzle, and utilized multiple tests to optimize the structural parameters. When each structural parameter is in the preferred range, it can be extremely Minimize the requirement on the pressure of the gas source to obtain a better ejection effect;

(3) An ejector-type low-pressure over-distance gas acceleration nozzle of the present invention adopts the aerodynamic structure formed by the cooperation of the ejector and the supersonic nozzle, which is more conducive to the establishment of supersonic flow and increases the reliability of the nozzle;

(4) An injection-type low-pressure ultra-distance gas acceleration nozzle of the present invention adopts the principle of "injection + supersonic speed" to greatly increase the spraying distance.

Description of drawings

Fig. 1 is a schematic diagram of the internal structure of a jet-type low-pressure super-distance gas acceleration nozzle of the present invention;

Fig. 2 is a three-dimensional structural schematic diagram of an ejector and a supersonic nozzle in an ejector-type low-pressure ultra-distance gas acceleration nozzle of the present invention.

Detailed ways

The following describes the present invention in detail, and the features and advantages of the present invention will become more clear and definite along with these descriptions.

The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. While various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

An injection type low-pressure ultra-distance gas acceleration nozzle, as shown in Figure 1, includes a rectification gas storage chamber 6, a supersonic nozzle 4 and an ejector 7;

The ejector 7 is a hollow circular platform structure, and the supersonic nozzle 4 is arranged inside the ejector 7; the supersonic nozzle 4 is a cylindrical structure with an ultrasonic acceleration flow channel 5 inside, and a contraction acceleration channel is formed between the supersonic nozzle 4 and the ejector 7 1; the supersonic nozzle 4 and the ejector 7 are connected to the rectification air storage chamber 6;

After the gas is rectified by the rectification gas storage chamber 6, it is divided into two paths, and the rectification gas storage chamber 6 enters the ultrasonic acceleration flow channel 5 and the contraction acceleration channel 1 respectively, and the gas ejected through the contraction acceleration channel 1 is discharged at the outlet of the supersonic nozzle 4 A low-pressure environment is formed, and the gas in the flow channel 5 is ejected at supersonic speed by injecting ultrasonic waves. The ejection method is used to effectively increase the spraying distance of the nozzle, and at the same time greatly reduce the requirements on the pressure of the air source.

Further, the supersonic acceleration channel 5 is a Laval channel.

Further, as shown in Figure 2, the axes of the supersonic nozzle 4 and the ejector 7 coincide; the supersonic nozzle 4 is fixed inside the ejector 7 through the connecting rod 9; the two ends of the connecting rod 9 are respectively connected to the supersonic nozzle 4 and the ejector 7, and are evenly distributed along the circumference of the ejector 7; there are 6 connecting rods 9.

Further, the ratio of the gas pressure in the rectified gas storage chamber 6 to the atmospheric pressure is 1.89-7:1, ensuring that the ejector 7 and the supersonic nozzle 4 can accelerate the air flow normally, that is, ensure that it enters the supersonic acceleration channel 5 and the contraction acceleration channel 1 The gas can be accelerated to the desired velocity.

Further, the Mach number at the outlet of the contraction acceleration channel 1 is 0.2 to 1, and this range can form a low-pressure environment at the outlet of the supersonic nozzle 4, which is beneficial for the supersonic nozzle 4 to establish a supersonic flow field at a lower gas source pressure; the supersonic nozzle 4 The Mach number of the outlet is 1.5-4.0, and the gas in the contraction acceleration channel 1 formed between the ejector 7 and the supersonic nozzle 4 has a good ejection effect on the gas within the above Mach number range.

Further, the ratio of the inlet diameter Φa of the ejector 7 to the outlet diameter Φe is 2.5-4:1, which ensures that the outlet of the contraction acceleration channel 1 can reach a predetermined Mach number under different gas source pressures.

Further, the ratio of the inlet diameter Φb of the supersonic nozzle 4 to the outlet diameter Φd of the supersonic nozzle 4 is 1.25 to 1.42:1, so that the flow through the supersonic nozzle 4 (that is, the flow through the supersonic acceleration flow channel 5) is greater than that through the ejector 7 and The flow between the supersonic nozzles 4 (ie the flow through the constriction acceleration channel 1).

Further, the ratio of the inlet diameter Φa of the ejector 7 to the inlet diameter Φb of the supersonic nozzle 4 is 1.1 to 1.2:1, which ensures the ratio of the inlet to the outlet of the Laval flow path; the ratio of the outlet diameter Φd of the supersonic nozzle 4 to the ultrasonic accelerated flow The ratio of the throat diameter Φc of the channel 5 is 1.1-11:1, which ensures the Mach number of the outlet of the supersonic nozzle 4 .

Further, the ratio of the height L1 of the rectification gas storage chamber 6 to the total height L2 of the gas acceleration nozzle is 0.2-0.3:1, and this range enables the rectification gas storage chamber 6 to have a better rectification effect.

Further, the inlet end of the ejector 7 is flush with the inlet end of the supersonic nozzle 4; the height of the supersonic nozzle 4 is smaller than the height of the ejector 7 to ensure a low-pressure environment at the outlet of the supersonic nozzle 4, which is conducive to establishing supersonic flow in the supersonic nozzle 4.

Further, the height ratio of the ejector 7 to the supersonic nozzle 4 is greater than or equal to 0.95:1 and less than 1:1.

The working principle of the present invention is: the gas flow is divided into two paths after being rectified by the rectifying gas storage chamber, one path is accelerated between the ejector and the supersonic nozzle, and a low-pressure environment is formed at the exit of the supersonic nozzle; one path is accelerated to supersonic speed by the supersonic nozzle, and the The injection method effectively increases the spraying distance of the nozzle, and at the same time greatly reduces the requirements for the pressure of the air source.

In Fig. 1 and Fig. 2, 1 is the contraction acceleration channel, 2 is the outlet of the supersonic nozzle (that is, the outlet of the supersonic nozzle 4), 3 is the outlet of the contraction acceleration channel 1, 4 is the supersonic nozzle, 5 is the supersonic acceleration flow channel, and 6 is Rectifier air storage chamber, 7 is the ejector, 8 is the inlet of supersonic nozzle 4, 9 is the connecting rod, 10 is the inlet of contraction acceleration channel 1, Φa is the diameter of the total air inlet (that is, the diameter of the inlet of ejector 7), and Φb is The diameter of the inlet of the supersonic nozzle 4, Φc is the diameter of the throat of the supersonic acceleration channel 5, Φd is the diameter of the outlet of the supersonic nozzle 4, Φe is the diameter of the total air outlet (that is, the diameter of the ejector 7 outlet), L1 is the height of the rectified air storage chamber 6, L2 is the total height of the gas acceleration nozzle.

The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions should not be construed as limiting the present invention. Those skilled in the art understand that without departing from the spirit and scope of the present invention, various equivalent replacements, modifications or improvements can be made to the technical solutions and implementations of the present invention, all of which fall within the scope of the present invention. The protection scope of the present invention shall be determined by the appended claims.

The content that is not described in detail in the description of the present invention belongs to the well-known technology of those skilled in the art.

Claims (3)

1. An ejector-type low-pressure ultra-distance gas acceleration nozzle, characterized in that it includes a rectifying gas storage chamber (6), a supersonic nozzle (4) and an ejector (7); The ejector (7) is a hollow circular platform structure, and the supersonic nozzle (4) is arranged inside the ejector (7); ) and the ejector (7) form a contraction acceleration channel (1); the supersonic nozzle (4) and the ejector (7) are connected with the rectification air storage chamber (6); After the gas is rectified by the rectification gas storage chamber (6), it is divided into two paths. The two paths of gas enter the ultrasonic acceleration channel (5) and the contraction acceleration channel (1) respectively from the rectification gas storage chamber (6). The contraction acceleration channel (1) is accelerated to form a low-pressure environment at the outlet of the supersonic nozzle (4), and the second gas is accelerated to supersonic speed in the ejection ultrasonic acceleration channel (5), and the supersonic acceleration channel (5) The gas is ejected at supersonic speed; The ultrasonic acceleration channel (5) is a Laval channel; The ratio of the inlet diameter Φa of the ejector (7) to the outlet diameter Φe is 2.5~4:1; The ratio of the inlet diameter Φb of the supersonic nozzle (4) to the outlet diameter Φd of the supersonic nozzle (4) is 1.25~1.42:1; The ratio of the inlet diameter Φa of the ejector (7) to the inlet diameter Φb of the supersonic nozzle (4) is 1.1~1.2:1; The ratio is 1.1~11:1; The ratio of the height L1 of the rectifying gas storage chamber (6) to the total height L2 of the gas accelerating nozzle is 0.2~0.3:1; The axes of the supersonic nozzle (4) and the ejector (7) coincide; the supersonic nozzle (4) is fixed inside the ejector (7) through the connecting rod (9); the two ends of the connecting rod (9) The ends are respectively connected to the supersonic nozzle (4) and the ejector (7), and are evenly distributed along the circumference of the ejector (7); there are 6 connecting rods (9); The inlet end of the ejector (7) is flush with the inlet end of the supersonic nozzle (4); the height of the supersonic nozzle (4) is smaller than that of the ejector (7). 2. An injection type low-pressure over-distance gas acceleration nozzle according to claim 1, characterized in that the ratio of the gas pressure in the rectification gas storage chamber (6) to the atmospheric pressure is 1.89~7:1. 3. An ejector-type low-pressure over-distance gas acceleration nozzle according to claim 1, characterized in that, the Mach number at the outlet of the contraction acceleration channel (1) is 0.2~1; the outlet of the supersonic nozzle (4) The Mach number is 1.5~4.0.

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