论文部分内容阅读
采用圆锥四孔高频压力探针测量了某涡轮不同叶尖间隙下转子出口的三维时均流场.结果表明转子出口参数均呈现明显的周期特性.叶尖间隙对转子出口流动品质有较大影响;间隙大时,泄漏流显著,对应的机匣二次流动较弱;间隙小时,机匣附近的二次流动较强.泄漏流区域的速度低,对应的相对总压小,损失大;泄漏流导致气流亏转,对应的静压高,膨胀程度小于主流,增大间隙,膨胀比变小,涡轮做功能力下降.
The four-hole conical four-hole high-frequency pressure probe was used to measure the three-dimensional time-average flow field of the rotor at different tip clearances of a turbine. The results showed that the rotor outlet parameters all showed obvious periodic characteristics. When the gap is large, the leakage flow is significant and the corresponding secondary casing flow is weak; when the gap is small, the secondary flow near the casing is strong.The velocity of the leakage flow area is low, corresponding to the relative total pressure is small, the loss is large; Leakage flow led to loss of air flow, the corresponding high static pressure, the expansion is less than the mainstream, increasing the gap, the expansion ratio becomes smaller, the turbine power decline.