Long duration small thrust nozzle diverging section
By designing a combined structure including a nozzle shell, a back wall insulation layer, a heat sink ring, and a diffuser section, and using carbon/carbon composite materials and tungsten-copper infiltrated materials, the ablation problem of the diffuser section of a solid rocket motor nozzle during long-term operation was solved, thereby improving the propellant specific impulse and engine reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- INNER MONGOLIA INST OF POWER MASCH
- Filing Date
- 2022-07-05
- Publication Date
- 2026-06-09
AI Technical Summary
The diffuser section of the nozzle of existing solid rocket engines suffers severe ablation during prolonged operation, resulting in a decrease in propellant specific impulse and causing engine failure and missile flight failure.
The structure employs a combination of nozzle shell, back wall insulation layer, front heat sink ring, middle heat sink ring, rear heat sink ring, baffle ring, rear insulation layer, diffuser section and throat liner. It uses carbon/carbon composite material and tungsten copper infiltrated material, and improves structural stability and material ablation resistance through adhesive bonding and threaded connection.
It improves the specific impulse of the propellant in solid rocket engines, reduces the ablation of the diffusion section, and enhances the reliability of the engine, making it suitable for solid rocket engines with an operating time of more than 100 seconds.
Smart Images
Figure CN115142988B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of solid rocket motor nozzle technology, specifically to a long-duration, low-thrust nozzle diffuser section. Background Technology
[0002] The diffuser section of a solid rocket motor nozzle is a crucial component. The ablation resistance of the diffuser section's insulation layer depends on the quality of the ablation layer; poor ablation layer stability can lead to engine failure and missile flight failure. Common materials for the diffuser section include carbon cloth / phenolic resin wound products, carbon fiber / phenolic resin molded products, and carbon / carbon composite materials.
[0003] The diffusion section using the above-mentioned materials is mainly used in solid rocket engines with an operating time of a few seconds to tens of seconds. When the operating time is more than 100 seconds, the diffusion section is severely ablated, and the propellant specific impulse decreases.
[0004] Existing solid rocket motor nozzle diffuser sections suffer severe ablation and propellant specific impulse reduction during prolonged operation (over 100 seconds). Summary of the Invention
[0005] The technical problem to be solved by the present invention
[0006] This invention provides a long-duration, low-thrust nozzle diffuser section to solve problems such as severe ablation of the diffuser section and significant decrease in propellant specific impulse in existing solid rocket motors that operate for extended periods.
[0007] The technical solution adopted by this invention to solve the technical problem
[0008] A long-duration, low-thrust nozzle diffuser section includes: a nozzle housing 4, a back wall insulation layer 1, a front heat sink ring 2, a middle heat sink ring 3, a rear heat sink ring 5, a baffle ring 6, a rear insulation layer 7, a diffuser section 8, and a throat liner 9. The back wall insulation layer 1 is located inside the nozzle housing 4. The front heat sink ring 2, the middle heat sink ring 3, and the rear insulation layer 7 are arranged adjacent to the back wall insulation layer 1 along the flow direction of the combustion gas. The throat liner 9 is located inside the back wall insulation layer 1, inside the front heat sink ring 2 and the middle heat sink ring 3, and inside the back wall insulation layer 4. The inner surfaces of the insulation layer 1 to the throat liner 9 are convergent surfaces; the diffuser section 8 is located inside the nozzle housing 4 and is adjacent to the middle heat sink ring 3, the rear heat sink ring 5 and the throat liner 9 along the gas flow direction, respectively. The inner surfaces of the throat liner 9 to the diffuser section 8 are diffuser surfaces; the rear heat sink ring 5 is located inside the nozzle housing 4 and is adjacent to the rear insulation layer 7 and the diffuser section 8 along the gas flow direction, respectively; the retaining ring 6 is located at the nozzle tail end and is used for axial support of the nozzle.
[0009] Furthermore, the mating surfaces of the back wall insulation layer 1, the front heat sink ring 2, the middle heat sink ring 3, the nozzle housing 4, the rear heat sink ring 5, the baffle ring 6, the rear insulation layer 7, the diffuser section 8, and the throat liner 9 are bonded together with adhesive.
[0010] Furthermore, the nozzle housing 4 and the retaining ring 6 are connected by threads.
[0011] Furthermore, the adjacent front heat sink ring 2, middle heat sink ring 3 and rear insulation layer 7 are provided with stepped surfaces.
[0012] Furthermore, the front heat sink ring 2, the middle heat sink ring 3, and the heat sink ring 5 are made of carbon / carbon composite materials.
[0013] Furthermore, the nozzle housing 4 and the retaining ring 6 are made of structural steel.
[0014] Furthermore, the materials for the diffusion section 8 and the throat liner 9 are selected as tungsten-copper infiltrated.
[0015] Beneficial effects obtained by the present invention
[0016] This invention provides a long-duration, low-thrust nozzle diffuser section with a simple structure and mature materials. It is suitable for solid rocket engines with an operating time of more than 100 seconds. It can improve the specific impulse of the solid rocket engine propellant and improve the ablation condition at the diffuser section, thereby improving the overall reliability of the solid rocket engine. Attached Figure Description
[0017] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:
[0018] Figure 1 : A schematic diagram of a diffuser section mechanism for a long-duration, low-thrust nozzle;
[0019] Wherein: 1-back wall insulation layer, 2-front heat sink ring, 3-middle heat sink ring, 4-nozzle shell, 5-rear heat sink ring, 6-barrier ring, 7-rear insulation layer, 8-diffuser section, 9-throat liner. Detailed Implementation
[0020] A long-duration, low-thrust nozzle diffuser section includes: a nozzle housing 4, a back wall insulation layer 1, a front heat sink ring 2, a middle heat sink ring 3, a rear heat sink ring 5, a baffle ring 6, a rear insulation layer 7, a diffuser section 8, and a throat liner 9. The back wall insulation layer 1 is located inside the nozzle housing 4. The front heat sink ring 2, the middle heat sink ring 3, and the rear insulation layer 7 are arranged adjacent to the back wall insulation layer 1 along the flow direction of the combustion gas. The throat liner 9 is located inside the back wall insulation layer 1, inside the front heat sink ring 2 and the middle heat sink ring 3, and the back wall insulation layer 9 is located inside the back wall insulation layer 1, inside the front heat sink ring 2 and the middle heat sink ring 3. The inner surfaces of the wall insulation layer 1 to the throat liner 9 are convergent surfaces; the diffuser section 8 is located inside the nozzle housing 4 and is adjacent to the middle heat sink ring 3, the rear heat sink ring 5 and the throat liner 9 along the gas flow direction, and the inner surfaces of the throat liner 9 to the diffuser section 8 are diffuser surfaces; the rear heat sink ring 5 is located inside the nozzle housing 4 and is adjacent to the rear insulation layer 7 and the diffuser section 8 along the gas flow direction; the retaining ring 6 is located at the nozzle tail end and is used for axial support of the nozzle.
[0021] Furthermore, the mating surfaces of the back wall insulation layer 1, the front heat sink ring 2, the middle heat sink ring 3, the nozzle housing 4, the rear heat sink ring 5, the retaining ring 6, the rear insulation layer 7, the diffuser section 8, and the throat liner 9 are bonded together with adhesive. The nozzle housing 4 and the retaining ring 6 are connected by threads. Adjacent front heat sink rings 2, 3, and 7 are provided with stepped surfaces. The front heat sink rings 2, 3, and 5 are made of carbon / carbon composite material. The nozzle housing 4 and retaining ring 6 are made of structural steel. The diffuser section 8 and throat liner 9 are made of tungsten-copper infiltrated material.
[0022] To make the objectives, features, and advantages of the technical solution proposed in this invention more apparent and understandable, the embodiments of the technical solution proposed in this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the proposed technical solution, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.
[0023] like Figure 1 As shown, during operation, the combustion gas is discharged at high speed from the front heat sink ring 2, throat liner 9, and diffuser section 8, thereby generating axial thrust.
[0024] like Figure 1 As shown, the front heat sink ring 2, the middle heat sink ring 3, and the heat sink ring 5 serve as heat sinks, dissipating heat from the throat liner 9 and the diffuser section 8, thereby improving the working environment of the throat liner 9 and the diffuser section 8.
[0025] like Figure 1 As shown, the back wall insulation layer 1 and the rear insulation layer 7 provide insulation, reducing the working temperature of the nozzle housing 4 and the retaining ring 6.
[0026] like Figure 1 As shown, the nozzle housing 4 is used to withstand the pressure of the gas inside the nozzle.
[0027] like Figure 1 As shown, the retaining ring 6 is used for axial support of the nozzle.
[0028] In practice, the mating surfaces of the back wall insulation layer 1, front heat sink ring 2, middle heat sink ring 3, nozzle housing 4, rear heat sink ring 5, retaining ring 6, rear insulation layer 7, diffuser section 8, and throat liner 9 are bonded together with adhesive. The nozzle housing 4 and retaining ring 6 are connected by threads. The back wall insulation layer 1 and rear insulation layer 7 are made of high-silica fiber / phenolic resin molded products. The front heat sink ring 2, middle heat sink ring 3, and heat sink ring 5 are made of carbon / carbon composite material. The nozzle housing 4 and retaining ring 6 are made of structural steel. The diffuser section 8 and throat liner 9 are made of tungsten-plated copper, which does not ablate during operation.
[0029] A certain type of solid rocket engine has an operating time of no less than 150 seconds and an average thrust of 1000N to 1200N. The nozzle diffuser section adopts the above-mentioned form. It has completed environmental tests, high-temperature, low-temperature, and normal-temperature ground test tests, and flight test assessments, all of which are normal.
Claims
1. A long-duration, low-thrust nozzle diffuser section, characterized in that, include: The nozzle housing (4), back wall insulation layer (1), front heat sink ring (2), middle heat sink ring (3), rear heat sink ring (5), baffle ring (6), rear insulation layer (7), diffuser section (8), and throat liner (9) are provided. The back wall insulation layer (1) is located inside the nozzle housing (4). The front heat sink ring (2), middle heat sink ring (3), and rear insulation layer (7) are arranged adjacent to the back wall insulation layer (1) along the flow direction of the combustion gas. The throat liner (9) is located inside the back wall insulation layer (1), inside the front heat sink ring (2), and inside the middle heat sink ring (3). 1) The inner surface of the throat liner (9) is a converging surface; the diffuser section (8) is located inside the nozzle housing (4) and is adjacent to the middle heat sink ring (3), the rear heat sink ring (5) and the throat liner (9) respectively along the flow direction of the gas. The inner surface of the throat liner (9) to the diffuser section (8) is a diffuser surface; the rear heat sink ring (5) is located inside the nozzle housing (4) and is adjacent to the rear insulation layer (7) and the diffuser section (8) respectively along the flow direction of the gas; the retaining ring (6) is located at the tail end of the nozzle and is used for axial support of the nozzle.
2. The long-duration low-thrust nozzle diffuser section according to claim 1, characterized in that: The mating surfaces of the back wall insulation layer (1), front heat sink ring (2), middle heat sink ring (3), nozzle housing (4), rear heat sink ring (5), baffle ring (6), rear insulation layer (7), diffuser section (8), and throat liner (9) are bonded together with adhesive.
3. The long-duration low-thrust nozzle diffuser section according to claim 1, characterized in that: The nozzle housing (4) and the retaining ring (6) are connected by threads.
4. The long-duration low-thrust nozzle diffuser section according to claim 1, characterized in that: The adjacent front heat sink ring (2), middle heat sink ring (3) and rear insulation layer (7) are provided with stepped surfaces.
5. The long-duration low-thrust nozzle diffuser section according to claim 1, characterized in that: The front heat sink ring (2), middle heat sink ring (3) and heat sink ring (5) are made of carbon / carbon composite materials.
6. The long-duration low-thrust nozzle diffuser section according to claim 1, characterized in that: The nozzle housing (4) and retaining ring (6) are made of structural steel.
7. The long-duration low-thrust nozzle diffuser section according to claim 1, characterized in that: The diffusion section (8) and throat liner (9) are made of tungsten-copper infiltrated material.