半開放形遠心羽根車通路内のCFD解析および二次流れ考察

抄録

In this study, CFD analysis was performed for the complex turbulence flow in an unshrouded centrifugal impeller with the leakage flow through a blade tip clearance. CFD analysis is influenced by the analysis conditions such as geometry and the number of mesh or turbulence model etc. In this paper, therefore, the validity of CFD analysis was examined by comparing the results of CFD with those of the previous experiments. SSG turbulence model was adopted with the stationary condition for incompressible flow. The relative velocities, the static and total pressures, the Reynolds stresses and the circumferential component of absolute velocity etc. were compared along the impeller passage. The impeller passage flows showed the same tendency with experiment. The similar tendency appeared also in the impeller performances. Moreover, the effect of the tip leakage vortex induced from the passage inlet on the secondary flow was discussed.