小尺寸应变天平设计方法研究

摘要

φ0.3m高超声速低密度风洞测力试验模型尺寸小、天平载荷小、流场总温高,天平防热结构设计难,刚度要求和灵敏度要求矛盾突出,测力天平的研制难度大.采用数值仿真和风洞试验相结合的研究方法,对应用于该情况下的内式天平在温度影响和结构设计方面进行了研究.采用有限元方法对天平温度影响和结构应力分布做了详细分析,并对分析结果进行了风洞试验验证.结果表明:在实现天平结构优化设计及提高天平设计的准确性和可靠性方面,有限元分析设计方法是非常有效的技术途径.%In the φ0.3m hypersonic low density wind tunnel,with the special test conditions of small model,small loads and high temperature,the design of the balance is very difficult.It is ambivalent to increase the rigidity and output signal of the balance in the same time.Thermal influence of the balance is serious.The research about the thermic influence and the structure design of the balance is carried out by numerical emulation and wind tunnel experiment.With the technique of finite element method,the temperature and stress distribution of the balance structure are analysed in detail.According to the results of the analysis,the balance structure is improved.Some results of the static calibration and the wind tunnel experiment are also provided.Through the comparison between the practice capability and the FEA results of the balance,the application of FEM to optimize balance structure and improve balance capability is validated.