An investigation of secondary-flow loss cores originating in turbine nozzle blade passages was conducted by means of flow visualization studies and detailed flow measurements. The degree of which blade surface velocity profiles affect the magnitude and concentration of loss cores was investigated by comparing three nozzle blade configurations.

In order to increase understanding of the origin of losses in a turbine, the secondary-flow components in the boundary layers and the blade wakes of an annular cascade of turbine nozzle blades (vortex design) were investigated. A detailed study was made of the total-pressure contours and, particularly, of the inner-wall loss cores down-stream of the blades.