No abstract

This paper presents some of the problems encountered in determining turbine stator blade performance from total pressure surveys downstream of the blade row. The stator blades were suitable for turbine cooling and incorprated thick trailing edges having a large included wedge angle between the suction and pressure surfaces. Blade performance was rated in terms of kinetic energy loss coefficients, which relate the frictional and mixing losses to the ideal kinetic energy that could be developed at a given overall pressure ratio. The loss coefficients were calculated from the results of total pressure surveys and flow conditions as determined by measurements at the inlet and outlet of the blade row. For the type of blading involved, it was determined that these loss coefficients were sensitive to the size of support stem of the total pressure probe used and the size and axial location of the probe sensing element. The effect of these variables on the results obtained are presented and desirable manners of taking survey data for this type of blading are discussed.