Inlet Skew and the Growth of Secondary Losses and Vorticity in a Turbine Cascade

This paper presents results of an experimental investigation into the effects of inlet skew on the flow field of a large-scale axial flow turbine cascade. The results are presented in terms of the development of the streamwise vorticity since, in classical terms, the streamwise vorticity generates the transverse velocity components that cause the generation of the secondary losses. Inlet skew is shown to have a profound effect on the distribution and magnitude of the generated losses. A number of correlations for the secondary losses are compared with the measured values and it is shown that the correlations are not adequate for accurate loss prediction purposes.