分立式导向器离心涡轮气动改型设计与流场分析

Modification design and flowfield analysis of a centrifugal turbine stage with discrete nozzles

对某高负荷低速较大扭矩单级冷气起动涡轮进行了原型机气动分析和改型机气动设计.该涡轮采用离心式流动,分立式导向器和冲击式转子.分析发现,该涡轮负荷系数极高而不追求高效率.为增大功率而进行的改型设计采取了加大流量而保持进气压强不变的技术方案.流场模拟结果显示,该改型设计在涡轮转子直径减小6%的情况下,在原型涡轮设计转速下及其140%转速下的输出功率各约为原型机的2倍和2.8倍.

For an air turbine with high loading, low rotational speed and greater torque output single-stage startup, aerodynamic analysis of prototype and aerodynamic modification design were conducted for achieving a more powerful shaft-power output. This turbine employed a centrifugal flow path, discrete nozzles and an impactive rotor. The flowfield analysis indicates that, this turbine has a very high loading coefficient, rather than a high adiabat- ic efficiency. A technical package was adopted in the modification design of increasing mass flow with almost the same turbine inlet total pressure. The flowfield simulation indicates that, when the rotor＇s diameter is reduced to 94% of the original turbine, the power output of the modified turbine is about 2 times and 2.8 times of the original one at both the rotation- al speed of 100% and 140% of the original one.