[0021] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention.
[0022] According to the design idea of the present invention, the two-dimensional direction of the lift can be designed according to the engine design requirements to design a dual-type adaptive rocket nozzle applied to a rocket-based combined cycle engine. The design method of the present invention is used to draw compensation flow. The axisymmetric arrangement of the suction channel and the pneumatic tab channel can design an axisymmetric adaptive rocket nozzle for rocket-based combined cycle engines.
[0023] Reference figure 1 , Applied to the adaptive rocket nozzle of the rocket-based combined cycle engine, the adaptive rocket nozzle is located in the internal runner 12 of the rocket-based combined cycle engine. The adaptive rocket nozzle includes a nozzle body 1, which is provided with a nozzle inner flow channel 2, and the nozzle inner flow channel 2 is sequentially provided with a nozzle straight section 13, a nozzle convergence section 4, and a nozzle expansion section 11. The end of the nozzle convergent section 4, that is, the smallest cross section of the nozzle inner flow channel 2 is the throat 5 of the nozzle inner flow channel 2, and the height of the throat 5 is Ht. The nozzle body 1 is provided with a supplementary flow suction channel 6 and a pneumatic tab channel 9. The supplementary flow suction channel inlet 3 is arranged on the outer side wall of the nozzle body 1, and the supplementary flow suction channel outlet 7 is arranged on the inner side wall of the nozzle body 1 downstream of the throat 5 of the nozzle body 1; The pneumatic tab channel inlet 8 is located on the inner side wall of the nozzle body 1 downstream of the supplementary flow suction channel outlet 7, and the pneumatic tab channel outlet 10 is provided on the outer side wall of the nozzle body 1.
[0024] The length d of the supplementary suction channel inlet 3 is in the range of 0.1Ht≦d≦2Ht, and the length c of the supplementary suction channel outlet 7 is in the range of 0.1Ht≦c≦2Ht. The supplementary suction channel outlet 7 and the throat The range of the distance and length a of 5 is 0.1Ht≦a≦4Ht, the angle between the supplementary flow suction channel 6 and the horizontal direction facing away from the nozzle is α, and the value range of α is 6°≦α≦45°. The suction channel 6 can be an equi-straight channel or an expanded channel, and the three-dimensional channel width e of the supplemental flow suction channel 6 ranges from 0.1Ht≦e≦2Ht.
[0025] The range of the length f of the pneumatic tab channel inlet 8 is 0.1Ht≦f≦2Ht, the value range of the distance b between the pneumatic tab channel inlet 8 and the throat is Ht≦b≦6Ht, and the pneumatic tab channel outlet 10 The value range of the length g of is 0.1Ht≦g≦2Ht, and the angle β between the pneumatic tab passage 9 and the horizontal direction away from the nozzle is 90°≦β≦160°. The pneumatic tab channel 9 may be an equal straight channel or a contracted channel, and the range of the channel width h of the pneumatic tab channel 9 is 0.1Ht≦h≦2Ht.
[0026] The nozzle body can be designed into a two-dimensional nozzle configuration and an axisymmetric nozzle configuration. The number of the supplementary flow suction channels and the number of pneumatic tab channels may be the same or different. The number of supplementary flow suction channels is in the range of 4-36, and the number of pneumatic tab channels is in the range of 4-36. If the nozzle body is an axisymmetric nozzle, multiple supplementary suction channels and multiple pneumatic tab channels are uniformly arranged on the nozzle body along the radial direction. In addition, multiple supplementary flow suction channels can also be distributed axisymmetrically with each other, and multiple pneumatic tab channels can also be distributed axisymmetrically with each other.
[0027] Both the supplemental suction channel 6 and the pneumatic tab channel 9 do not need to be equipped with control switches and inlet and outlet baffles. According to the working conditions of the engine, the working conditions of the supplementary suction channel 6 and the pneumatic tab channel 9 can be adjusted and switched by themselves . When the rocket-based combined cycle engine is in the sub-combustion or super-combustion mode, the supplemental flow suction channel can flow into the nozzle through the supplementary flow suction channel according to the pressure difference generated inside and outside the nozzle body. The nozzle expansion section of the flow channel, and at the same time, the pneumatic tab channel will be aerodynamically blocked due to the airflow inside the nozzle body under this working condition. When the rocket-based combined cycle engine is in the ejection mode, the pneumatic tab channel can generate pneumatic tabs on the outside of the nozzle body according to the pressure difference between the inside and outside of the nozzle body, which interacts with the air flow outside the nozzle body. The effect forms a flow vortex, which strengthens the mixing of the rocket jet ejected by the nozzle body with the external air flow; at the same time, the supplementary flow suction channel will be aerodynamically blocked due to the air flow inside the nozzle body under this working condition.
[0028] Therefore, the present invention can adaptively adjust the internal and external airflow of the rocket by using the supplemental flow suction channel 6 and the aerodynamic tab channel 9 according to its own operating conditions, and strengthen the internal and external airflow in the ejection mode. Blending can shorten the length of the engine, reduce the bottom resistance of the rocket nozzle in the sub-combustion and super-combustion modes, and has a simple structure and adjustable effects, which has strong practical value.
[0029] The foregoing descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modification, equivalent replacement, improvement, etc., made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.