厘米级向心涡轮的三维流动特征分析

Flow behavior analysis in a radial inflow turbine for very small aero-engines

关键词:  涡轮  数值仿真  流动分布  叶片  设计

Key words:  Turbine  Numerical simulation  Flow distribution  Blade  Design

摘要:

为详细研究厘米级向心涡轮的内部流动规律,在向心涡轮级的三维粘性计算中引入掺混面的概念,对一台叶轮直径35mm的向心涡轮三维流场进行了数值模拟,得到多个转速下的特性曲线。与试验结果进行的对比表明计算结果准确可靠。预测了在设计转速下的向心涡轮特性曲线,得到这台向心涡轮设计点流量为0 11kg/s,落压比1 93,总压绝热效率0 82,并对向心涡轮设计点附近的流动特征进行了详细的分析。

Abstract:

Radial inflow turbines are founded in very small aero-engine due to their ease of manufacture, low cost and high efficiency at low Reynolds. In order to improve the performance, it is necessary to understand the physical flow behavior. The flow characteristics of one 35mm radial inflow turbine were analyzed by the 3-D viscous code.Computational results agree well with measurements.Based on the numerical simulation, the parameter characters of this turbine were obtained, and then the design point can be affirmed. The flow behavior at this design point was described in detail. Based on the good physical understanding,some advices to improve the performance of this turbine were discussed.