浮环密封泄漏特性数值计算与试验

为了研究不同压差、温度和转速下浮环密封的泄漏特性,建立了CFD数值计算模型,计算分析了某型航空发动机浮环密封泄漏特性。针对转速引起的泄漏量变化,提出了通过有限元方法计算不同转速下密封跑道的离心膨胀量对流场尺寸进行更改;针对温度、压差引起的流体状态参数改变,通过状态方程进行计算,并对本构方程中相关参数进行重新确定。为有效验证数值计算模型的有效性,进行了全工况条件下浮环密封泄漏特性试验。结果表明:随着压差升高,数值计算得到的泄漏量不断趋近试验结果,在压差大于等于0.1 MPa后,数值计算得到的泄漏量与试验结果的平均偏差在6.08%~9.43%。

Numerical calculation and experiment on leakage characteristics of floating ring seal

To study the leakage characteristics of floating ring seal under different temperatures, pressures and rotational speeds, a numerical calculation model with CFD was built. The leakage characteristics of floating ring seal used in a specific aero engine were analyzed. For the change of leakage caused by rotational speed, a way was proposed to calculate the centrifugal expansion of rotor at different rotational speeds by finite element method, and to change the flow field size according to the centrifugal expansion. The change of state parameters of fluid caused by temperature and differential pressure was calculated by state equation, and the related parameters in constitutive equation were redefined. To verify the numerical calculation model, experimental study of leakage characteristics of floating ring seal under simulating real conditions was developed. Results showed that with the increase of differential pressures, computational results kept approaching the experimental results; when the differential pressures were greater than or equal to 0.1 MPa, the average deviations between computational results and experimental results were between 6.08%-9.43%.