塔式太阳能热板式吸热器内部支撑结构的热应力分析

Thermal Stress Analysis for Internal Support Structure of Plate-type Heat Pipe Receiver on Solar Power Tower

基于顺序耦合的有限元计算方法对塔式太阳能热板式吸热器结构的热应力进行模拟,发现内部拉杆和受光板连接处周围出现热应力集中,是影响结构稳定的危险区。当增大拉杆的外径时,危险处的局部热应力只是很小程度的减小;随着拉杆内径的增加,局部热应力也会增加,但是热应力的整体分布变得更加均匀化;当冷凝板的温度增大时,局部热应力明显减小,而且整体热应力的分布更加均匀化。通过热应力分析得到拉杆的外径为20mm,内径为12mm,整个吸热内部取16根拉杆时,受光板上的热应力最大值为23.61MPa;310s材料800℃的许用应力为8MPa,使用时可满足安定性准则。

The solar receiver’s thermal stress was simulated with sequentially-coupled thermal stress analysis method to show that the junction between the pull rod and light-receiving plate is a dangerous part where the maximum thermal stress concentrates.With the pull rod’s outer-diameter increasing,the local thermal stress declines slightly;and with the pull rod’s inner-diameter increasing,the local thermal stress increases and the thermal stress’distribution becomes more uniform;increasing the condensing plate ’s temperature can result in the decrease of local thermal stress and can make the thermal stress’distribution more uniform.As for the optimal structure of employing 16-pull rods in the design,their outer diameter stays at 20mm with 12mm for the inner diameter,the maximum thermal stress of the light-receiving plate can be 23.61MPa.The 8MPa al-lowable stress for the light-receiving plate made of 310s material can ensure a reliable operation.