Investigation for Loss Generation Mechanisms of Flow in Turbomachinery by Using Curved Square Duct

(3rd Report, Influence of Curved Angle)

Abstract

In a series of present studies, the flows within the stationary curved ducts are analyzed numerically with the aerodynamic or the geometrical parameters affecting the loss generation caused by the passage vortex within a passage of a turbomachinery. In the former reports, the inlet boundary layer thickness and the inlet velocity distortion were taken as the aerodynamic parameter and the aspect ratio of the cross-section was chosen as the geometrical parameter. In this report, the effects of the curved angle of the bend on the loss generation caused by the passage vortex are examined by relating the bend of curved duct to the blade-to-blade surface of an axial flow turbine cascade. The curved angle is changed from 90 to 160 degrees by 10 degrees with fixing the length of arc for the mean radius of curvature of the bend or with fixing the mean radius of curvature.