CN-114991988-B - Telescopic tail nozzle

CN114991988BCN 114991988 BCN114991988 BCN 114991988BCN-114991988-B

Abstract

The invention provides a telescopic tail nozzle which is connected with the tail of an engine, and comprises a connecting component, wherein the connecting component comprises a connecting element and a first cylindrical thin-wall pipe, the air inlet end of the first cylindrical thin-wall pipe is detachably connected with the tail of the engine through the connecting element, the straight section comprises a second cylindrical thin-wall pipe, the air inlet end of the second cylindrical thin-wall pipe is sleeved on the outer wall of the air outlet end of the first cylindrical thin-wall pipe, and the round square section is connected with the air outlet end of the second cylindrical thin-wall pipe. The problem of engine installation difficulty in modern stealth aircraft is solved, engine installation workload is reduced through the telescopic tail pipe, and sealing of the tail pipe in a working state is achieved by utilizing different linear expansion coefficients of different materials.

Inventors

LV GUANGQUAN
YING PEI
FAN JINGFENG
ZHAO DALIN
SHEN SIYING

Assignees

中国科学院工程热物理研究所
中国科学院工程热物理研究所

Dates

Publication Date: 20260421
Application Date: 20220526
Priority Date: 20220526

Claims (4)

1. A telescopic tail pipe for connection to the tail of an engine (4), comprising: the connecting assembly comprises a connecting element (6) and a first cylindrical thin-walled tube (1), and the air inlet end of the first cylindrical thin-walled tube (1) is detachably connected with the tail part of the engine (4) through the connecting element (6); The straight section comprises a second cylindrical thin-wall pipe (2), and the air inlet end of the second cylindrical thin-wall pipe (2) is sleeved on the outer wall of the air outlet end of the first cylindrical thin-wall pipe (1); The round rotating square section (3), the round rotating square section (3) is connected with the air outlet end of the second cylindrical thin-wall tube (2); The first cylindrical thin-wall pipe (1) and the second cylindrical thin-wall pipe (2) are made of materials with different linear expansion coefficients; The radius of the first cylindrical thin-wall tube (1) is The linear expansion coefficient of the material of the first cylindrical thin-wall tube (1) is The radius of the second cylindrical thin-wall tube (2) is The linear expansion coefficient of the material of the second cylindrical thin-wall tube (2) is The gas temperature of the engine (4) is The indoor temperature is The radial clearance between the first cylindrical thin-walled tube (1) and the second cylindrical thin-walled tube (2) is , wherein, ; When the temperature is in the room, the first cylindrical thin-walled tube (1) can axially move along the second cylindrical thin-walled tube (2); when the gas temperature is reached, the first cylindrical thin-walled tube (1) and the second cylindrical thin-walled tube (2) are radially sealed.
2. A telescopic jet nozzle according to claim 1, characterized in that the connection means of the connection element (6) are one or a combination of several of a screw connection, a clamp connection, a flange connection.
3. The telescopic tail pipe according to claim 1, characterized in that the straight section further comprises a guiding section (5), the guiding section (5) being a horn structure arranged at the inlet side of the second cylindrical thin-walled pipe (2).
4. A telescopic tail pipe according to claim 3, characterized in that the radius of the guiding section (5) is larger than the radius of the second cylindrical thin-walled tube (2).

Description

Telescopic tail nozzle Technical Field The specification relates to the technical field of aircraft tail nozzles, and in particular relates to a telescopic tail nozzle. Background Modern stealth aircraft are usually provided with embedded S-shaped air inlets and round-square tail nozzles in front of and behind an engine for stealth design consideration. The air inlet channel and the tail spray pipe are buried in the machine body, the installation accuracy requirement is high, and the air inlet channel and the tail spray pipe are connected with an engine and have sealing requirements. When the engine is installed, the installation space is reserved in front and back, in order to ensure the installation space of the engine, the air inlet channel or the tail spray pipe is usually required to be detached, the installation precision of the whole power system is easy to influence, and the workload of detaching the engine is greatly increased. The other design thought is to use a sectional design for the tail nozzle, remove the connecting section when installing the engine, and reload the connecting section after the engine is installed, so the design thought can reduce a part of disassembly and assembly workload, but has extremely high requirement on the installation accuracy, and the problems that the connecting section with too small gap cannot be installed or the gap is too large to be sealed and the like are easy to occur, and the tail nozzle is difficult to apply in engineering practice. Disclosure of Invention In view of this, the embodiments of the present disclosure provide a telescopic tail pipe, which can achieve the purposes of easy disassembly and assembly and self-sealing of the tail pipe. The embodiment of the specification provides the following technical scheme: a retractable tail pipe for connection to an engine tail, comprising: the connecting assembly comprises a connecting element and a first cylindrical thin-wall pipe, and the air inlet end of the first cylindrical thin-wall pipe is detachably connected with the tail part of the engine through the connecting element; The straight section comprises a second cylindrical thin-wall pipe, and the air inlet end of the second cylindrical thin-wall pipe is sleeved on the outer wall of the air outlet end of the first cylindrical thin-wall pipe; The round-turning square section is connected with the air outlet end of the second cylindrical thin-wall tube. Further, the materials of the first cylindrical thin-walled tube and the second cylindrical thin-walled tube are materials with different linear expansion coefficients. Further, the radius of the first cylindrical thin-wall pipe is R 1, the linear expansion coefficient of the first cylindrical thin-wall pipe material is theta 1, the radius of the second cylindrical thin-wall pipe is R 2, the linear expansion coefficient of the second cylindrical thin-wall pipe material is theta 2, the gas temperature of the engine is Tgas, the indoor temperature is Troom temperature, and the radial clearance between the first cylindrical thin-wall pipe and the second cylindrical thin-wall pipe is delta, wherein delta is less than or equal to (R 1θ1-R2θ2)(T Gas combustion -T Room temperature ). Further, the first cylindrical thin-walled tube is axially movable along the second cylindrical thin-walled tube when at the indoor temperature. Further, the first cylindrical thin-walled tube is radially sealed from the second cylindrical thin-walled tube when at the gas temperature. Further, the connection mode of the connecting element is one or a combination of a plurality of screw connection, bolt connection, clamp connection and flange connection. Further, the straight section further comprises a guide section, and the guide section is of a horn structure arranged on the air inlet side of the second cylindrical thin-wall tube. Further, the radius of the guide section is greater than the radius of the second cylindrical thin-walled tube. Compared with the prior art, the beneficial effects that above-mentioned at least one technical scheme that this description embodiment adopted can reach include at least: the problem of engine installation difficulty in modern stealth aircraft is solved, engine installation workload is reduced through the telescopic tail pipe, and sealing of the tail pipe in a working state is achieved by utilizing different linear expansion coefficients of different materials. Drawings In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art. FIG. 1 is a schematic view of the overall structure of a telescopic tail pipe according to an em