环管型燃烧室火焰筒壁温气热耦合数值模拟

针对某型燃气轮机运行时回流式环管型燃烧室的火焰筒常发生烧蚀和裂纹,需获取其火焰筒壁温分布特点,进行分析以提出改进措施.全面考虑固体导热和辐射传热、气体与固体间的对流换热以及火焰和燃气的辐射,对燃烧室进行三维气热耦合数值模拟计算,获取流场、温度场以及壁温分布信息,并结合实验验证了三维气热耦合数值模拟能够较有效预测火焰筒壁温分布.由模拟结果知该型火焰筒壁温未超过设计值1 223K,但在联焰管与筒体连接处以及多个主燃孔处的温度较高、温度梯度较大,需要对这些部位的冷却方案进行改进.

Coupled heat transfer numerical simulation of wall temperature of can-annular combustor flame tube

The wall temperature distribution of a can-annular reversed combustor flame tube was obtained and analyzed to ameliorate the flame tube design, since the flame tube was often ablated partly and cracked when a gas turbine running. The distributions of flow field, temperature field and wall temperature were obtained by the method of three-dimensional numerical simulation of coupled heat transfer, while heat conduction and radiation of solid, heat convection between gas and solid, radiation of flame and flue gas were took into account. The simulation result was checked by experiments, so the temperature distribution of flame tube can be predicted with the method of three-dimensional numerical simulation of coupled heat transfer. According to the simulation result, the wall temperature of combustor flame tube doesn't exceed the design value 1223K, but the temperature and temperature gradient are relatively high at several primary holes and the joint of the flame crossover tube and flame tube, and the cooling design of these parts needs to be improved.