Turbo-machines (e.g. compressors, blowers and pumps) obtain energy transfer from their rotating impellers to fluid flowing through them, and they are used for a wide range of purposes obtaining pressurized fluid flow. The author created theoretical models to clearly describe the complicated flow phenomena in impellers and in diffusers, based on the fluid dynamic theory. Furthermore, he succeeded in inventing a new diffuser to control a part of the complicate flow, which improved performance of compressors dramatically.


(Communicated by Hidesato ITO, M.J.A.)