四级轴流透平的性能研究

Research on the Four-stage Axial Flow Turbine Performance

以汉诺威大学四级轴流实验涡轮为对象,利用当今先进的流体数值模拟软件NUMECA对其不同工况下的内部流场进行了数值模拟,获取同一工况下流场损失分布特点,从而为透平的优化提供理论基础。通过改变涡轮出口背压的方法,画出不同工况下该四级轴流透平的特性曲线,并在特性曲线上获得效率最高点、流量最大值点、流量最小值点。并通过对比获得最大效率点处不同级透平的流场损失分布。利用相同的方法分析同一工况或不同工况下整个四级透平的流场的损失分布。

The experimental four-stage axial flow turbine of Hannover University was targeted in this article. NUMECA, the advanced fluid numerical simulation software, was used to simulate the internal flow field under the same condition to access to the loss distribution of the same operating conditions, thus providing a theoretical basis for optimization of turbine. By changing the back pressure of turbine exports, the turbine characteristic curve under different conditions of the four-stage axial flow turbine was drawn, and the highest efficiency point, and the maximum and minimum point of flow on characteristic curve were obtained. Comparing the profiles under maximum efficiency point conditions, flow field distribution of different cascades was obtained. The loss distribution of flow field throughout the four-stage turbine under the same condition or different conditions was analyzed with the same method of analysis.