热流温度场下功能梯度板的热问题研究

功能梯度材料因其内部组分沿着空间位置连续变化,能有效缓解热应力集中等现象,在高超音速飞行器的热防护系统设计中具有良好的应用前景.以金属-陶瓷功能梯度板为研究对象,探讨在不同热环境下功能梯度板热传导、热变形和热应力的变化规律.首先,基于功能梯度材料的幂律分布模型,分析了线性温度场、正弦温度场、热流温度场和非线性温度场四种...

Study on thermal problems of functionally graded plate under heat fluxtemperature field

Functionally graded material(FGM)has good application prospects in the design of thermal protection system of hypersonic aircraft because of the continuous variation of internal components along the space position,which can effectively alleviate thermal stress concentration and other phenomena.Taking the metal-ceramic functionally graded plate as the research object,the changing rules of heat conduction,thermal deformation and thermal stress of the functionally graded plate under different thermal environments were discussed.Firstly,based on the power-law distribution model of FGM,the effects of four kinds of thermal environments,including linear temperature field,sinusoidal temperature field,heat flux temperature field and nonlinear temperature field,on the physical properties of FGM were analyzed.Secondly,based on the idea of finite element layered modeling,the finite element model of functionally graded plate was established by Python programming.The changing rules of heat conduction,thermal deformation and thermal stress of functionally graded plate in heat flux temperature field under different plate thickness,ceramic volume fraction index and heat flux density and other parameters were simulated and analyzed.Finally,the method of improving the thermal protection performance of functionally graded plate based on parameter control was discussed.The results showed that when using FGM to design aircraft thermal protection panel, the ceramic volumefraction index should be less than 5.0;under heat flux temperature field, the thickness of the functionallygraded plate was 7.2-9.0 mm, and the ceramic volume fraction index was 1.0-2.5, which could realizethe light weight and efficient heat insulation of functionally graded plate;when the heat flux density wasconstant, it was of vital importance to adjust the flight time to guarantee the safety of aircraft;the heatflux density should be limited to 5-10 mW/mm2 to control the deformation of functionally graded plate.The research conclusions have reference value for the thermal protection design of metal-ceramicfunctionally graded plate under heat flux temperature field.