Editorial

This volume contains eight papers on turbomachinery covering CFD applications, detailed flow measurements on unsteady flow, new design methods and control devices, and conventional empirical approaches. Shi and Tsukamoto succeeded in predicting pressure fluctuations caused by the interaction between a centrifugal impeller and diffuser vanes, using a Navier-Stokes code with standard $k−ε$ turbulence model. Using a commercial code, Gu et al. succeeded in predicting the performance of a single-stage centrifugal compressor and studied the volute/diffuser flow in detail at design and off design conditions. By combining a scheme called the Single-Sweep Method with an algebraic eddy viscosity model, Kochevsky made a parametric study of the energy loss in annular diffusers with a rotating hub and inlet flow swirl, with the purpose of minimizing the loss in annular diffusers. These papers suggest that CFD is now becoming capable of predicting not only steady flows under design flow conditions, but...