INVISCID ANALYSIS OF TRANSONIC OSCILLATING CASCADE FLOWS USING A DYNAMIC MESH ALGORITHM

A locally implicit total-variation-diminshing scheme and a rigid-defor mable dynamic mesh algorithm are formulated on the quadrilateral-trian gular meshes. The unsteady Euler equations with moving domain effects are solved in a Cartesian coordinate system, For transonic flows aroun d an oscillating cascade of four biconvex blades with different oscill ation amplitudes, reduced frequencies, and interblade phase angles, th e calculated distributions of magnitude and phase angle of the first h armonic dynamic pressure difference coefficient agree better with expe rimental data than those from linearized theory and related numerical results on triangular meshes in most of the eases, Also, the numerical wiggles of instantaneous blade surface pressure coefficient distribut ions, which appeared on the triangular meshes, are eliminated, From th e instantaneous pressure and Mach number contours, the unsteady flow p henomena, such as periodical characteristics, pressure wave and shock behaviors, and time-variations of zones with high Mach number gradient normal to the blade surfaces, are investigated, Furthermore, the lift coefficient distributions indicate that the oscillation amplitude, re duced frequency, and interblade phase angle all have significant effec ts on the transonic oscillating cascade flows.