Hui Yang
Zhejiang Sci-Tech University, China
Title: Numerical investigation on instability of flow around planar cascade of aerofoils based on energy gradient theory
Biography
Biography: Hui Yang
Abstract
Study of flow around planar cascade of aerofoils is an important basis for the research of flow field in fans and compressors with aerofoil impeller. The energy gradient theory is used to analyze the flow stability of flow around planar cascade of aerofoils under low Reynolds number. The influence of attack angle and airfoil blade spacing on the flow stability was studied. The flow was governed by the unsteady incompressible Navier-Stokes equations coupled with the Spalart-Allmaras turbulent model. The finite volume method was used to discretize the governing equations and the Semi-Implicit method for pressure linked equation algorithm was employed to iterate the system of the equations. It was found that the distribution of the energy gradient function K was in agreement with the variation of the flow field and flow instability could be showed by the energy gradient function K. The position of flow separation at the trailing edge of airfoil was corresponding to the distribution of the energy gradient function K at high angle of attack. It was found that the development of the flow stability was much affected by the energy gradient function K from the comparison of the flow field for different cases. The research results can be used for further study of flow stability in the turbomachinery.
