Abstract A new approach is provided for blade design on stream surface of revolution based on a novel image plane theory of cascade blading.A flow solver in differential integral formulation for analyzing the flow field of a given geometry is transformed into a design method by coupling with a contour modification model.In this method the classical slip condition is replaced by other boundary conditions.In such a way the prescribed velocity or pressure distribution can be imposed directly on the blade.Since the blade shape is compatible with the velocity requirement,a nonzero velocity component normal to the blade wall evolves from the flow calculation.This normal velocity is then used to reset the wall parallel to the new flow field,using a transpiration technique.The procedure is repeated until the calculated velocity distribution converged to the required one.Numerical results of an actual turbine nozzle show that the present method can provide a practical blade without strict requirement for its initial shape.Another important aspect of this method is the ability to design and analyze a blade with identical code.
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