Abstract
This paper discusses the flow instabilities in a vaned diffuser by using CFD. A commercial code with the standard κ-ε turbulence model was used for the present work. It was found that the flow instabilities in the vaned diffuser; i. e., rotating stall, alternate blade stall, and asymmetric stall, could be simulated by the present calculations. These instabilities were observed in a range with negative slope of the pressure performance curve of the diffuser. In addition, the experiments were carried out for the purpose of visualizing the flow field under the stalled condition, and the results were compared with the calculations.
