旋流杯燃烧室头部冷却设计及其对壁温的影响

Cooling design for head of swirl-cup combustor and its effect on wall temperature

在保证燃烧室流场结构相似、流量分配相当的基础上,针对旋流杯燃烧室开展平直孔板耦合挡溅板和斜向导流孔板耦合导流护罩两种头部冷却结构的设计,通过高温高压扇形燃烧室试验和三维数值仿真对冷却性能进行评估和分析。结果表明:平直孔板耦合挡溅板冷却结构的壁温远高于斜向导流孔板耦合导流护罩冷却结构的壁温,其主要原因是斜向导流孔板耦合导流护罩冷却方式为带有一定角度的收敛双锥形冷却构型,可通过引导气流吹除燃烧室头部近壁面角涡区,防止燃气在靠近壁面处产生高温区,从而降低燃烧室头部壁温。斜向导流孔板耦合导流护罩冷却结构的壁温大幅度降低,且温度分布均匀,提高了头部的冷却性能,增强了燃烧室头部结构的可靠性。

On the basis of ensuring similar flow field structure and equivalent flow distributions of the combustor,two cooling structures were designed for the head of a swirl cup combustor:a straight orifice coupled with a splash plate and an inclined flow guide orifice coupled with a guide shield.The cooling performances of the two structures were evaluated and analysed through high-temperature and high-pressure tests of fan-shaped and three-dimensional numerical simulations.Results showed that the wall temperature of the cooling structure of the straight orifice coupled with the splash plate was much higher than that of the inclined fluid guide orifice coupled with the guide shield,primarily owing to the fact that the latter one had a converging biconical cooling configuration with a certain angle which can blow off the angular vortex near the wall of the head by guiding the airflow,prevent the gas from heating up a high temperature area near the wall surface,thus reducing the wall temperature.The wall temperature of the cooling structure of the inclined guide orifice coupled with the guide shield was greatly reduced,and the temperature distribution was more uniform,which improved the cooling performance of the head and enhanced the reliability of the head structure of the combustion chamber.