摘要
本文研究了利用导热逆问题(IHCP)原理测算固体热扩散系数α和比热C_p的原理和方法。在最优化问题分析中,得到了α和C_p的无因次敏感度系数X_α^+和X_(C_p)^+的表达式,论证了X_α^+=-X_(C_p)^+,并揭示出它们的变化规律,为拓展IHCP方法的实施提供了理论依据。采用不锈钢或聚氨酯材质的球体或无限长圆柱试件的实验结果表明,即使测算时间r=6～1200秒,α值的测算最大偏差ε_(max)=1.97%～2.07%。但若在聚氨酯试件外壁面设置测点时,ε_(max)将高达22.09%。
The theory and experimental investigation with inverse heat conduction problem(IHCP) methods are carried out for determining thermal diffusivity a and specific heat C_p of solids. In the analysis of optimization,the expressions of dimensionless sensitivity coefficients of thermal diffusivity X_a^+ and specific heat Xc_p^+ are obtained for infinite cylinder and sphere samples,the variation patterns are revealed and equation X_a^+=—Xc_p^+ is also verified. All these results provide theory basis and guidance for applications. The experimental results show that the maximum deviations ε_(max) of measured and calculated values for thermal diffusivity are—1.58%～2.09% to infinite cylinder or sphere samples which are made of polyurethane and stainless steel ,but if the measure location of temperature is set on the outside wall of samples, ε_(max) will increase even up to 22.09%.
出处
《计量学报》
CSCD
1996年第3期181-184,共4页
Acta Metrologica Sinica
基金
天津市自然科学基金
关键词
热扩散系数
比热
导热逆
计算
传热学
Thermal diffusivity
Specific heat
IHCP principle
Sensitivity coefficient
