遠心ポンプにおけるディフューザベーン近傍からの噴流によるディフューザ旋回失速抑制効果の分析

抄録

The operating range of centrifugal pumps at non-design points is greatly limited by unsteady phenomena such as diffuser rotation stall (DRS), which is a problem in the industrial field. To expand the operating range of a centrifugal pump, a hole was drilled near the front edge of the diffuser vane, and the DRS suppression effect of the jet flow passing through the hole was experimentally investigated. Although the DRS suppression effect of the jet flow at the leading edge of the vane was confirmed, the hole was not examined in detail. In this study, the internal flow was investigated by numerical fluid dynamics analysis to examine more effective holes.

The internal flow at low flow rates for a diffuser with a hole near the vane leading edge was found to cause DRS when the hole was smaller than the core of negative pressure due to the detached vortex generated at the diffuser vane leading edge. Increasing the diameter of the hole near the leading edge of the vane increases the DRS suppression effect, but the pump head is significantly reduced.