中文摘要：

给出了积分平均法、超临界数法两种关于有相变物质流体的自然对流强度评价方法，并与常规算术平均温度法进行了对比分析．通过给定两种表观比热容随温度变化的关系式，即正弦函数和高斯函数，获得了Rayliegh数的修正系数，以及随加热表面温度的变化规律．同时，还可以根据所介绍的分析方法预测获得最佳自然对流传热的工况，对实现蓄热或传热的最佳控制有指导意义．

英文摘要：

The intensity of Rayliegh-Benard convection in a fluid layer dispersed with phase-changematerial varla corre ods ble lati particles was studied. Instead of using the conventional mean temperature method, two new were proposed for evaluating the intensity of convection in a horizontal fluid layer with strongly apparent specific heat. One method was by introducing a modified Ste number in a Nu-Ra on or using the integrally averaged specific heat over the layer in calculating the Rayliegh number. The other method was by using the supercriticality （Ra/Rac） as the intensity parameter. The critical Rayliegh number Rac could be calculated with the linear stability theory. After giving two kinds of correlating functions of non dimensionalized apparent specific heat functions with respect to temperature, the influences of their amplitudes and phase angles on the critical Rayliegh number were investigated. Results showed that the two proposed methods were more rational comparing with the convectional method. The optimum convective mode predicted by the two methods was in agreement with previous experimental results.