敷设热障涂层气冷叶片温度分布数值研究

Numerical investigation on temperature distribution of an air-cooled and thermal barrier coating blade

针对一种内冷通道射流腔交替布置在压力面和吸力面的叶片冷却结构,利用FLUENT软件对敷设热障涂层的气冷叶片温度分布进行了三维共轭传热计算,分析了热障涂层厚度对叶片金属基体表面温降水平的影响,同时对比了有/无考虑燃气与叶片表面辐射换热的叶片表面温度分布差异.研究结果表明:在叶栅通道燃气流进口总温为1 600K、冷却气流进口总温为700K的条件下,当冷却气流与主流流量之比约为7.47%、热障涂层厚度为0.2mm时,该叶片冷却结构的最高温度可以控制在1100K以内;在假设热障涂层表面发射率与金属壁面发射率相同的前提下,厚度0.15～0.35mm的热障涂层可获得的最大降温大约在80～180K范围内;考虑/不考虑辐射换热的叶片表面最大温差可以达到60K.

For a serpentine internal cooling flow path in which the impingement cavities were located on the pressure side and suction side alternately, the commercial code FLUENT was used for three-dimensional conjugate heat transfer simulation to determine temperature distribution on an air-cooled and thermal barrier coating （TBC） blade. The effect of TBC thickness on the temperature decreasing capacity for blade metal surface was analyzed, and the temperature difference with/without considering radiation heat transfer was also analyzed. In the case of primary flow temperature 1600 K and cooling flow temperature 700 K, the maximum temperature for the present air-cooled blade can be controlled within 1 100 K when the cooling massflow is about 7.47% of the primary massflow and the TBC thickness was 0.2 mm. The temperature decreasing capacity for TBC reaches about 130-180 K when the TBC thickness is 0.15-0. 35mm assuming the emissivity of TBC is the same as that of blade metal surface. The temperature difference with/without considering radiation heat transfer is about 60K.