| Rocket is one of the main types of conventional ammunition,which has the advantages of long range,high power,intensive fire and low launching recoil.Taking a rocket rocket as the research object,the numerical heat transfer calculation of the three-dimensional nozzle of the rocket solid rocket engine was carried out and compared with the experimental results of static ground heat transfer.Secondly,fluid analysis software Fluent and ANSYS structural analysis software were used to conduct unsteady flow thermo-solid coupling numerical calculation of the rocket combustor nozzle integrated engine structure,to obtain the flow field and thermal structure characteristics of solid rocket engine,and to compare the performance of solid rocket engine without thermal protection structure.Then the influence of thermal insulation material characteristic parameters,mass flow rate in internal flow field and Mach number of gas flow in external flow field on the working process of solid rocket engine is studied.At last,the whole projectile model of rocket is established,and the unsteady flow thermo-solid coupling calculation is carried out for its flight process,and the flow field distribution and warhead,tail heat flow and structure change under different flight Mach number and Angle of attack are obtained.Specific contents include:(1)The three-dimensional heat transfer numerical simulation of a rocket rocket solid rocket engine is compared with the static ground temperature test to verify the reliability of the numerical simulation method.(2)The non-steady-state flow thermo-mechanical coupling numerical simulation of a combustor-integrated engine of a rocket is carried out,and the temperature distribution characteristics of the internal flow field and the stress-strain characteristics of the shell material are obtained.The internal flow field temperature changes of the combustion chamber and the nozzle are analyzed,and the stress and strain,convective heat transfer coefficient and heat flux density of the inner wall surface of the engine casing are changed.The effect of the presence or absence of thermal protection structures on engine performance was then compared.(3)The influence of thermal insulation material characteristic parameters,mass flow rate in internal flow field and Mach number of gas flow in external flow field on the working process of solid rocket engine is studied.With the increase of the gas mass flow rate in the combustion chamber,the temperature of the inner wall ofthe combustion chamber shell increases,the exhaust velocity at the nozzle outlet increases,the static pressure at the outlet increases,and the radial thrust of the engine increases.Different thermal insulation materials have significant influence on the temperature propagation of combustion chamber shell.The airflow Mach number in the external flow field has a significant influence on the temperature of the outer wall of the shell.In the case of subsonic velocity,forced convection heat transfer and heat conduction in the internal flow field play a decisive role in the influence of external wall temperature,and aerodynamic heat generation in the external wall temperature plays a decisive role in the case of supersonic velocity.(4)The unsteady aerodynamic thermoelastic simulation of a rocket was carried out to study the characteristics of outflow field distribution under different Mach number and attack Angle,and analyze the influence of aerodynamic heat on warhead and tail structure.The results show that the temperature and stress strain reach the maximum at the warhead vertex,the displacement change is the most obvious,and the change decreases along the axis of the projectile.As the Mach number increases,the temperature and displacement change obviously.The leading edge of the fin has the highest temperature,the upper end and the lower end produce displacement and bending,and the contact position between the wing root and the rocket part produces stress concentration. |
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