中文摘要：

为了使涡轮与发动机在较宽广的工况范围内保持良好的匹配，通过调节涡轮喷嘴环的转角，改变涡轮的流通面积，使涡轮的流量特性和效率特性发生变化．运用三维数值模拟技术，对JK90S可调喷嘴涡轮喷嘴冲角特性进行了数值计算和流场分析．结果表明，当仅改变喷嘴环的入口冲角，保持喷嘴入口的总温、总压和出口静压不变，喷嘴环的气流冲角小于某一值时，级效率对于喷嘴环入口来流的冲角不敏感；当冲角大于此值时，级效率将急剧降低，此时级效率主要受喷嘴环效率的影响．

英文摘要：

In efforts to make the turbine and the operation condition of the engine in a wide range maintain good matching, we made adjustments to the angle of the turbine nozzle ring, the turbine circulation area, and changes to the flow characteristic and efficiency of turbine characteristics. By using 3D numeric simulation techniques, the nu- merical calculation and flow field analysis on characteristics of nozzle incidence of JK90S variable nozzle turbine were carried out. The results indicate that by only changing the incidence of nozzle ring, and keeping the inlet total temperature, total pressure and outlet static pressure fixed, the stage efficiency keeps steady when incidence is less than a certain value and drops rapidly when incidence is larger than the value. Under the same condition, the noz- zle efficiency plays a significant role in stage efficiency.