贴附射流蒸发传质法确定多孔介质热质扩散系数测定方法的研究

Study of the Measuring Method of Determining Thermal Mass Diffusivity of Porous Materials by Evaporating Mass Transfer with Adherent Jet

提出一种确定热质扩散系数ａｔ的测定方法。根据反问题原理，在假定前扩散系数ａｍ为含湿量的线性函数、热梯度系数为常数的条件下，利用自行研制的贴附射流式对流蒸发实验装置，对胶凝材料石膏板、加气混凝上砌块等含混多孔材料的热质扩散系数ａｔ的确定进行了测量研究和优化处理；并对多变量寻化时存在多个极值点的情况下，如何获得最优解进行了探讨，最终得到两种适于测试情况的有效方法：（ｌ）合理选初值；（２）利用修改的变量轮换法进行全局优化①。

A measuring method of determining thermal mass diffusion coefficient at is proposed in this paper. According to the principle of inverse problems, we Suppose that the mass diffusivity am is a linear function of moisture content and the thermogradient coefficient δ is constant measurement of thermal mass diffusivity of gelatinous material:gypsum slab, concrete slab with entrined air has been performed using the self-made convection evaporation device with adherent jet. The discussion of how to find out the optimum has been performed in many extreme values under multivariable optimization conditions. Two methods for soling the problem have been found out: (l) Selecting rational initial values; (2) Performing total optimization using revisory variable substitute method.