不同厚度储能单元内相变传热强化及经济效益

摘要

以正十八烷为相变材料,在等热流加热条件下,对不同厚度大长宽比矩形储能单元内的相变材料融化传热过程进行试验.通过对融化相变过程中储能单元被加热面的温度检测,验证融化过程中存在相变材料固相部分的重力沉降效应,该效应强化了相变传热.试验结果表明,不同厚度的储能单元均在倾斜角为90°时融化相变传热的效果最佳;通过经济效益分析,得储能单元厚度为20 mm,倾斜角为90°时,在提高相变传热的基础上经济效益最佳.%Through the experiment method,it is investigated that the melting processes of n-octadecane within the rectangle energy storage units of large aspect ratio under the boundary condition of constant heat flux.The surface temperatures are measured to confirm the heat transfer enhancement of the effect of gravity settling.The results show that the optimized inclination angle is 90° for all the energy storage units with different thicknesses.Based on high heat transfer enhancement,enconomic benefit analysis method is introduced.In conclusion,the case of the thickness of 25°mm and the inclination angle of 90° for the melting process within the energy storage unit is optimum.