1710 Correlation Between Stall Inception Patterns and Rotor Design Parameters for a Variable-Pitch Axial-Flow Fan
Details
Numerical and experimental studies were carried out to clarify the flow mechanism behind stall inception at three stagger-angle settings for the rotor blades of a variable-pitch axial-flow fan. When a short length-scale stall cell was observed, tip-leakage vortex breakdown occurred, and a three-dimensional separation vortex developed When a long length-scale stall cell was observed without the short length-scale stall cell, this breakdown also occurred, but the separation vortex did not develop. When a modal disturbance was observed, a separation vortex developed, but the tip-leakage vortex breakdown did not occur. The numerical and experimental results show that the diffusion factor and attack angle at the rotor tip were the aerodynamic parameters that influenced the change in the tip-leakage vortex and the development of the tree-dimensional separation vortex.
