CN-121976894-A - Secondary injection type needle bolt injector and injection method thereof

CN121976894ACN 121976894 ACN121976894 ACN 121976894ACN-121976894-A

Abstract

The invention relates to a secondary injection type needle plug injector and an injection method thereof, wherein the secondary injection type needle plug injector comprises a needle plug and an outer nozzle, and the outer nozzle is sleeved at the middle part of the needle plug and forms an annular first injection channel with the middle part of the needle plug; the needle bolt comprises an outer sleeve and an inner sleeve, wherein two axial ends of the outer sleeve are of an open structure, one axial end of the inner sleeve is of a blocking structure, the other axial end of the inner sleeve is of an open structure, the inner sleeve is sleeved in the outer sleeve and forms a second injection channel with the outer sleeve, one open end of the inner sleeve is fixedly connected with the open end of the outer sleeve in a sealing manner, one blocked end of the inner sleeve is positioned in the outer sleeve, a plurality of inner swirl nozzles are arranged in the second injection channel, one ends of the inner swirl nozzles are connected with the inner sleeve and communicated with the inner cavity of the inner sleeve, the other ends of the inner swirl nozzles are connected with the outer sleeve and communicated with the first injection channel, the inner swirl nozzles extend and are arranged along the tangential direction of the inner sleeve, and a plurality of injection holes are formed in the outer sleeve.

Inventors

MENG JINGYAN
LIU YANG
WANG SHUANG
LU MING
LI RUI
ZHANG PENG
ZHOU WEI
JI FENGLAI
HUANG SHIQI
JIN FUGUI
FU JUNFENG

Assignees

九州云箭(北京)空间科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260203

Claims (10)

1. The secondary injection type needle bolt injector is characterized by comprising a needle bolt and an outer nozzle, wherein the outer nozzle is sleeved at the middle part of the needle bolt and forms an annular first injection channel with the middle part of the needle bolt; The needle bolt comprises an outer sleeve and an inner sleeve, both axial ends of the outer sleeve are of an open structure, one axial end of the inner sleeve is of a blocking structure, the other axial end of the inner sleeve is of an open structure, the inner sleeve is sleeved in the outer sleeve and forms a second injection channel with the outer sleeve, one open end of the inner sleeve is fixedly connected with one open end of the outer sleeve in a sealing manner, and one blocked end of the inner sleeve is positioned in the outer sleeve; The inner rotary flow nozzle is arranged in the inner sleeve in an extending mode along the tangential direction of the inner sleeve, the inner cavity of the inner sleeve is used as a rotary flow injection channel, a plurality of injection holes are formed in the outer sleeve and are arranged close to an opening structure of the inner sleeve, and the injection holes are located on the outer side of the outer nozzle and are communicated with the outer portion of one axial end of the outer nozzle.
2. The secondary injection needle bolt injector according to claim 1, wherein the inner side wall of the outer nozzle comprises a closing-in section, a connecting section and a flaring section which are axially and sequentially arranged, the connecting section is of a funnel-shaped structure, the big head end is connected with the flaring section, the small head end is connected with the closing-in section, the first injection channel sequentially comprises a collecting cavity section, a converging section and an injecting section along the direction close to the injection hole, the injecting section is formed between the closing-in section and the outer sleeve, the converging section is formed between the connecting section and the outer sleeve, the collecting cavity section is formed between the flaring section and the outer sleeve, and the injecting section is arranged close to the injection hole.
3. A secondary injection needle bolt injector according to claim 1, wherein the injection holes are arranged radially of the outer sleeve.
4. A secondary injection needle bar injector as in claim 1, wherein a plurality of said internal flow nozzles are uniformly disposed along the circumference of said needle bar.
5. The secondary injection needle plug injector according to claim 1, wherein the blocking structure of the inner sleeve is a convex cambered surface structure, and the joint of the outer sleeve and the inner sleeve is a convex cambered surface structure.
6. A secondary injection pintle injector as in claim 1 wherein the ratio of the length of the inner flow nozzle to the diameter of the inner flow nozzle is greater than 2.
7. The secondary injection needle bolt injector according to claim 1, wherein a bottom plate is fixed to an outer side wall of one end of the outer nozzle, which is close to the inner sleeve plugging structure, a middle plate is fixed to an outer side wall of one end of the outer sleeve, which is far away from the inner sleeve opening structure, and a propellant conveying interval is formed between the bottom plate and the middle plate.
8. A liquid rocket engine, characterized by comprising the secondary injection needle plug injector of any one of claims 1 to 7, and further comprising an engine body, wherein one end of the outer nozzle, which is close to the inner sleeve plugging structure, is mounted on a bottom plate of the head of the combustion chamber of the engine body, and one end of the outer sleeve, which is far away from the inner sleeve opening structure, is mounted on a middle plate of the head of the combustion chamber of the engine body.
9. A method of insufflating using the secondary insufflating pintle insufflator of any one of claims 1 to 7 comprising the steps of: the first propellant is gathered in a first injection channel, and the first injection channel axially injects the first propellant, and the process is one injection; the first injection channel also distributes a part of the first propellant into an inner rotary nozzle, the inner rotary nozzle injects the first propellant into the inner cavity of the inner sleeve to form a rotary flow and is sprayed out of the open structure of the inner sleeve at an atomization angle beta to form a first spraying fan, and the process is secondary injection; The second propellant is injected from one end of the outer sleeve far away from the inner sleeve opening structure, is rectified through the second injection channel, is sprayed outwards through the injection hole, collides with the first propellant injected at one time to form a second spraying fan with an inclination angle alpha, and is atomized and combusted, wherein beta/alpha is more than 1.1.
10. The method of injecting as defined in claim 9, wherein said atomization angle α is calculated as: Wherein LMR is a local momentum ratio, TMR is a total momentum ratio, BF is a blockage rate, m is the number of injection holes, c is the injection hole diameter, P is the pintle diameter, Q1 is the second propellant flow, V1 is the second propellant injection speed, Q2 is the first propellant flow, and V2 is the first propellant injection speed; the calculation formula of the atomization angle beta is as follows: Wherein, the The effective section coefficient is that A is the geometric characteristic, n is the number of internal flow nozzles, b is the diameter of the internal flow nozzles, and D is the diameter of the swirl injection channel.

Description

Secondary injection type needle bolt injector and injection method thereof Technical Field The invention relates to the technical field of pintle injectors for rocket engines, in particular to a secondary injection pintle injector and an injection method thereof. Background The pintle injector is widely applied to a combustion chamber of a liquid rocket engine, is a core component for atomizing and burning tissue propellant, and has the advantages of good combustion stability, convenient manufacturing and processing and the like. However, when the injector is applied to a burner in a state of a pre-combustion chamber or a generator in which the bias mixing ratio (the actual flow ratio of the two propellants deviates from the flow ratio of the propellant to be fully reacted), the injection of the pintle injector has the problems that the combustion efficiency is low due to the deviation of the momentum ratio from a design value, the pintle head is easy to burn due to the backflow of central fuel gas and the like, so that the injection of the pintle injector is applied to the generator and the pre-combustion chamber in a small amount. Disclosure of Invention The invention provides a secondary injection type needle bolt injector and an injection method thereof, aiming at solving one or more of the technical problems in the prior art. The invention provides a secondary injection type needle bolt injector, which comprises a needle bolt and an outer nozzle, wherein the outer nozzle is sleeved at the middle part of the needle bolt and forms an annular first injection channel with the middle part of the needle bolt; The needle bolt comprises an outer sleeve and an inner sleeve, both axial ends of the outer sleeve are of an open structure, one axial end of the inner sleeve is of a blocking structure, the other axial end of the inner sleeve is of an open structure, the inner sleeve is sleeved in the outer sleeve and forms a second injection channel with the outer sleeve, one open end of the inner sleeve is fixedly connected with one open end of the outer sleeve in a sealing manner, and one blocked end of the inner sleeve is positioned in the outer sleeve; The inner rotary flow nozzle is arranged in the inner sleeve in an extending mode along the tangential direction of the inner sleeve, the inner cavity of the inner sleeve is used as a rotary flow injection channel, a plurality of injection holes are formed in the outer sleeve and are arranged close to an opening structure of the inner sleeve, and the injection holes are located on the outer side of the outer nozzle and are communicated with the outer portion of one axial end of the outer nozzle. The invention has the beneficial effects that two injection channels are formed by arranging the pintle and the outer nozzle, different propellants of the two injection channels form the cyclone spray fan in a secondary injection mode, backflow fuel gas can be effectively prevented from ablating the pintle head, the function is reliable, the momentum ratio of primary injection impact is reduced by secondary injection, the combustion efficiency of the injector is improved by the fact that the spray fan formed by secondary injection impacts the spray fan formed by primary injection, and the invention has the advantages of simple structure and convenience in processing. The inner swirl nozzles are components for realizing the core function of the invention, the first propellant outside the pintle is introduced into a swirl injection channel in the pintle through a plurality of tangentially arranged inner swirl nozzles and is swirl-sprayed out, and the gaps between the inner swirl nozzles in the inner swirl nozzles can rectify the second propellant and spray out from the injection holes. On the basis of the technical scheme, the invention can be improved as follows. Further, the internal flow nozzles are arranged in an extending mode along the tangential direction of the inner sleeve, and the inner cavity of the inner sleeve is used as a rotational flow injection channel. The adoption of the further scheme has the beneficial effect that the swirl injection channel is arranged, so that the swirl injection of the propellant can be realized. Further, the inside wall of outer nozzle includes the binding off section, linkage segment and the flaring section that the axial arranged in proper order, the linkage segment be funnel-shaped structure and big head end with the flaring section is connected, little head end with the binding off section is connected, first injection passage is along being close to the direction of injection hole is including collecting chamber section, convergence section and injection section in proper order, the binding off section with form the injection section between the outer sleeve, the linkage segment with form the convergence section between the outer sleeve, the flaring section with form collecting chamber section between the outer sleeve, the injecti