相变蓄热材料导热系数对太阳能通风墙性能的影响

Effect of Thermal Conductivity on Performance of Solar Chimney With Phase Change Accumulator

通过对相变蓄热型太阳能烟囱模型通风蓄放热变化过程的计算,分析比较不同相变蓄热墙导热系数对太阳能烟囱性能的影响.计算结果表明:吸热板最大表面温度随着相变蓄热墙导热系数的增大越接近相变蓄热墙的相变温度;蓄热阶段,入口平均风速随着相变蓄热墙导热系数的增大而减小;放热阶段,入口平均风速随着相变蓄热墙导热系数的增大反而越大;相变蓄热墙导热系数越大,蓄热型太阳能烟囱系统16h的累计通风量越高,但在导热系数增大到0.66 W·(m·K)-1后,再增大材料导热系数,累计通风量几乎不再增加.

The influence of different thermal conductivities of phase change and thermal storage wall on the performance of solar chimney was analyzed and compared through the calculation of the ventilation and heat storage or release change process of the phase change and thermal storage type of solar chimney model.The results show that the maximum temperature of the heat absorber plate is more close to the phase change temperature with the increase of the thermal conductivity of the phase change and heat storage wall.The average inlet wind velocity reduces with the increase of the thermal conductivity for the process of heat storage,while increases for the process of heat release.The higher the thermal conductivity of the phase change and thermal storage wall is,the higher the cumulative ventilation in16hours of the regenerative solar chimney system will be.But when the thermal conductivity is increased to0.66W·(m·K)-1,the cumulative ventilation has almost no increase even if increasing the thermal conductivity of the material.