Impact of flow-passage geometric parameters on the aerodynamic performance of a low-pressure guide vane assembly

A numerical simulation of a prototype and modified low-pressure guide vane assembly was conducted by using a numerical calculation method. The meridian flow passage of the latter has a relatively long casing transition section with the casing assuming a rather great outer-wall divergence angle. Gas flow is liable to separate at the outer wall, resulting in a deterioration of the cascade inlet flow of the guide vane assembly. The results of the numerical study indicate that the optimized design of the casing outer wall profile and blade contour has improved the overall aerodynamic performance of the guide vane assembly. In the case of identical calculation-domain initial conditions there is a marked reduction of outlet energy loss of the guide vane assembly.