平屋顶水平封闭方腔空气层厚度数值分析

Numerical Analysis of Air Layer Thickness of Horizontally Enclosed Square Cavity

为分析平屋顶水平封闭方腔作为保温系统时其内部空气层的相对最佳厚度,通过建立二维数值模型,选择"Presto!"压力插值格式及SIMPLE(Semi-Implicit Method for Pressure-Linked Equations)解耦算法,计算了在不同边界温差和边界材料导热系数下平屋顶水平封闭方腔内辐射传热量和对流换热量及其随空气层厚度的变化.在一定条件下,通过对计算结果进行回归分析,得到平屋顶水平封闭方腔在不同温差和不同边界材料导热系数下的相对最佳空气层厚度值.

In order to analyze the relatively optimal air layer thickness of the horizontally enclosed square cavity based on its thermal insulation, this paper established a two-dimensional numerical model and calcu- lated the radiation and convection heat transfer in the horizontally closed square cavity at different tempera- ture differences and different thermal conductivities of the solid boundary material by using the ＂Presto!＂ pressure interpolation scheme and SIMPLE （semi-implicit method for pressure-linked equations） decou- pling algorithm. The relative optimal air layer thickness values of the horizontally closed square cavity at different temperature difference and thermal conductivity of the boundary material under a certain condition were obtained from the regression analysis of the results.