The part-load performance of gas turbine is of great importance due to the consideration of running time spent at part power, and Variable Geometry Turbine (VGT) is an important way to meet the requirements. Effect of variable geometry guide-vane with cylindrical endwalls on part-load turbine stage performance is quantified by detailed analysis of aerodynamic characteristics. The turbine stage characteristics of corrected mass flow, corrected output power and efficiency are presented to investigate the VGT performance under the condition of four off-design rotating angles. In addition, the flow field, the loss distribution and the leakage flow are analyzed for different rotating angles. Results show that both the corrected mass flow and the corrected output power increase as the vane throat area is increased, the total leakage area and the shroud area are increased with the increase of rotating angle, whereas the hub leakage area is decreased, and the total pressure loss and the entropy change of variable geometry vane are both increased with the decrease of vane throat area.

中文翻译：

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带有圆柱端壁的可变几何导向叶片对涡轮级性能的影响

燃气轮机的部分负荷性能非常重要，这是因为要考虑在部分功率上花费的运行时间，而可变几何涡轮机（VGT）是满足要求的重要方法。通过详细分析空气动力学特性，可以量化具有圆柱形端壁的可变几何形状的导向叶片对部分负荷涡轮机级性能的影响。提出了修正质量流量，修正输出功率和效率的涡轮级特性，以研究在四个非设计旋转角条件下的VGT性能。另外，分析了不同旋转角度下的流场，损失分布和泄漏流。结果表明，修正后的质量流量和修正后的输出功率都随着叶片喉部面积的增加而增加，