A high reliability multi-layer composite nozzle

Abstract

The present invention discloses a high-reliability multilayer composite nozzle, comprising a front section metal shell, a rear section metal shell, a front section heat insulation lining, a front section erosion-resistant lining, a rear section metal shell, a rear section erosion-resistant lining and a throat lining; the front end of the tapered inner wall of the rear section metal shell is provided with an annular positioning platform, the inner surface of the annular positioning platform is a cone surface that expands backwards; the front end outer wall of the rear section heat insulation lining is pressed onto the inner cone surface of the front end annular positioning platform of the tapered inner wall of the rear section metal shell; the rear end of the tapered inner wall of the rear section metal shell is provided with an annular stop; the rear end annular stop of the tapered inner wall of the rear section metal shell is pressed into the rear end surface of the rear section erosion-resistant lining. The multilayer composite nozzle of the present invention prevents the double-layer composite lining from being peeled off prematurely during the operation of the engine, thereby improving the reliability of engine operation.

Description

Technical Field

[0001] The invention relates to a high-reliability multi-layer composite material nozzle, belonging to the technical field of engines. Background Art

[0002] With the increase in the range requirements of rocket engines, the requirements for the main engine component nozzle are also getting higher and higher. The traditional single-layer thermal protection structure nozzle can no longer meet the harsh working environment of long working time and high-energy propellant, so the composite structure nozzle with large expansion ratio and multi-layer thermal protection has become a design trend. The more thermal protection layers and the more complex the structure, the more quality and reliability problems will be caused in the nozzle processing, operation and storage. The composite structure nozzle is generally composed of the front and rear sections of the nozzle. The front and rear sections of the nozzle are respectively composed of the front and rear section metal shells and the double-layer composite material lining. The double-layer composite material lining is molded twice in two layers on the front and rear section metal shells. However, the bonding ability between the double-layer composite material lining and the metal shell is poor, especially between the double-layer composite material lining and the rear section metal shell. During the operation of the engine, when it is subjected to the huge axial backward gas thrust, because the lining is not supported by the metal shell backward, the lining will be peeled off from the rear section metal shell, and the requirements of the established technical indicators cannot be met. Summary of the invention

[0003] The purpose of the present invention is to solve the problem that the lining of the rear section of a traditional composite structure nozzle is separated from the rear section metal shell in advance when the engine is working, and to provide a high-reliability multi-layer composite material nozzle.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] A high-reliability multilayer composite nozzle of the present invention comprises a front section metal shell and a rear section metal shell connected by front and rear threads, a front section heat insulation lining and a front section scour resistant lining molded twice on the conical inner wall of the front section metal shell in two layers, a rear section heat insulation lining and a rear section scour resistant lining molded twice on the conical inner wall of the rear section metal shell in two layers, and a throat lining bonded to the inner side of the connection between the front section metal shell and the rear section metal shell;

[0006] An annular positioning platform is provided at the front end of the conical inner wall of the rear section metal shell, and the inner surface of the annular positioning platform is a conical surface expanding backward; when the rear section thermal insulation lining is fixed by molding, the front end outer wall of the rear section thermal insulation lining is pressed onto the inner conical surface of the annular positioning platform at the front end of the conical inner wall of the rear section metal shell; an annular baffle is provided at the rear end of the conical inner wall of the rear section metal shell; when the rear section scour-resistant lining is fixed by molding, the rear end annular baffle of the conical inner wall of the rear section metal shell is pressed into the rear end surface of the rear section scour-resistant lining.

[0007] The rear end of the annular positioning platform and the conical inner wall of the rear metal shell are transitioned through an arc surface; the angle of the inner cone of the annular positioning platform is 5 to 10 degrees, preferably 5 degrees. This structure avoids internal cracks in the double-layer lining due to stress concentration during the molding process.

[0008] The upper edge of the front end surface of the annular baffle is a stepped surface, and each step of the stepped surface of the upper edge of the front end surface of the annular baffle is a cambered transition.

[0009] The outer wall of the rear section thermal insulation lining is provided with axially uniformly distributed annular positioning grooves. When the rear section scour-resistant lining is fixed by molding, the inner wall of the rear section scour-resistant lining is pressed into the annular positioning groove of the outer wall of the rear section thermal insulation lining to strengthen the axial bonding force between the rear section thermal insulation lining and the rear section scour-resistant lining.

[0010] Positioning holes are provided on the conical side walls of the front metal shell and the rear metal shell to strengthen the axial bonding force between the front metal shell and the rear metal shell and the inner lining.

[0011] Beneficial Effects

[0012] The multi-layer composite nozzle of the present invention can improve the molding processability of the double-layer composite liner and improve the processing quality without reducing the product function and performance, ensure the axial bonding force between the metal shell and the double-layer composite liner, avoid the double-layer composite liner from being peeled off prematurely during the operation of the engine, and improve the operating reliability of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic diagram of the structure of the multilayer composite material nozzle of the present invention;

[0014] Figure 2 It is a schematic structural diagram of the rear section of the nozzle in the multilayer composite nozzle of the present invention;

[0015] Figure 3 It is a partial enlarged view of the front end of the rear section of the nozzle in the multilayer composite material nozzle of the present invention;

[0016] Figure 4 It is a partial enlarged view of the rear end of the nozzle rear section in the multilayer composite nozzle of the present invention;

[0017] In the figure, 1-front section metal shell; 2-front section thermal insulation lining; 3-front section scour-resistant lining; 4-throat lining; 5-rear section metal shell; 6-rear section thermal insulation lining; 7-rear section scour-resistant lining. DETAILED DESCRIPTION

[0018] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0019] Example

[0020] like Figure 1 As shown, a high-reliability multilayer composite nozzle of the present invention comprises a front section metal shell 1 and a rear section metal shell 5 connected by front and rear threads, a front section heat insulation lining 2 and a front section scour-resistant lining 3 molded twice on the conical inner wall of the front section metal shell 1 in two layers, a rear section heat insulation lining 6 and a rear section scour-resistant lining 7 molded twice on the conical inner wall of the rear section metal shell 5 in two layers, and a throat lining 4 bonded to the inner side of the connection between the front section metal shell 1 and the rear section metal shell 5;

[0021] The schematic diagram of the nozzle rear section is as follows: Figure 2-4 As shown;

[0022] An annular positioning platform is provided at the front end of the conical inner wall of the rear section metal shell 5, and the inner surface of the annular positioning platform is a conical surface expanding backwards, and the rear end of the annular positioning platform and the conical inner wall of the rear section metal shell 5 are transitioned by an arc surface; the angle of the inner conical surface of the annular positioning platform is 5 degrees; when the rear section heat insulation lining 6 is molded and fixed, the front end outer wall of the rear section heat insulation lining 6 is pressed on the inner conical surface of the annular positioning platform at the front end of the conical inner wall of the rear section metal shell 5, such as Figure 3 As shown; the rear end of the tapered inner wall of the rear section metal shell 5 is provided with an annular baffle; the upper edge of the front end surface of the annular baffle is a stepped surface, and each step of the stepped surface of the upper edge of the front end surface of the annular baffle is a cambered transition; when the rear section scour-resistant lining 7 is fixed by molding, the rear end annular baffle of the tapered inner wall of the rear section metal shell 5 is pressed into the rear end surface of the rear section scour-resistant lining 7, as shown Figure 4 shown.

[0023] The outer wall of the rear section thermal insulation lining 6 is provided with axially uniformly distributed annular positioning grooves. When the rear section scour-resistant lining 7 is molded and fixed, the inner wall of the rear section scour-resistant lining 7 is pressed into the annular positioning groove of the outer wall of the rear section thermal insulation lining 6 to strengthen the axial bonding force between the rear section thermal insulation lining 6 and the rear section scour-resistant lining 7.

[0024] Positioning holes are provided on the conical side walls of the front metal shell 1 and the rear metal shell 5 to strengthen the axial bonding force between the front metal shell 1 and the rear metal shell 5 and the inner lining.

Claims

1. A high-reliability multi-layer composite nozzle, comprising a front section metal shell and a rear section metal shell connected by front and rear threads, a front section heat insulation lining and a front section scour resistant lining molded twice on the conical inner wall of the front section metal shell in two layers, a rear section heat insulation lining and a rear section scour resistant lining molded twice on the conical inner wall of the rear section metal shell in two layers, and a throat liner bonded to the inner side of the connection between the front section metal shell and the rear section metal shell; characterized in that: An annular positioning platform is provided at the front end of the conical inner wall of the rear section metal shell, and the inner surface of the annular positioning platform is a conical surface expanding backward; when the rear section thermal insulation lining is fixed by molding, the front end outer wall of the rear section thermal insulation lining is pressed onto the inner conical surface of the annular positioning platform at the front end of the conical inner wall of the rear section metal shell; an annular baffle is provided at the rear end of the conical inner wall of the rear section metal shell; when the rear section scour-resistant lining is fixed by molding, the rear end annular baffle of the conical inner wall of the rear section metal shell is pressed into the rear end surface of the rear section scour-resistant lining.

2. A high reliability multi-layer composite nozzle as claimed in claim 1, characterized in that: The rear end of the annular positioning platform and the conical inner wall of the rear metal shell are transitioned through an arc surface.

3. A high reliability multi-layer composite nozzle as claimed in claim 1, characterized in that: The angle of the inner cone surface of the annular positioning platform is 5 to 10 degrees.

4. A high reliability multi-layer composite nozzle as claimed in claim 1, characterized in that: The angle of the inner cone surface of the annular positioning platform is 5 degrees.

5. The high reliability multi-layer composite nozzle according to claim 1, characterized in that: The upper edge of the front end surface of the annular baffle is a stepped surface.

6. A high reliability multi-layer composite nozzle as claimed in claim 5, characterized in that: Each step on the upper step surface of the front end surface of the annular baffle is a cambered transition.

7. The high reliability multi-layer composite nozzle according to claim 1, characterized in that: The outer wall of the rear section heat insulation lining is provided with axially uniformly distributed annular positioning grooves. When the rear section scour-resistant lining is fixed by molding, the inner wall of the rear section scour-resistant lining is pressed into the annular positioning groove of the outer wall of the rear section heat insulation lining.

8. A high reliability multilayer composite nozzle according to any one of claims 1 to 7, characterized in that: Positioning holes are provided on the conical side walls of the front metal shell and the rear metal shell.

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