A computational fluid dynamic method for rotating stall in a single stage axial compressor

This thesis elucidates the development of a computer program to model the unsteady phenomenon of propagating (or rotating) stall in a single stage, axial compressor. This development involved the modification of an existing computer program designated as ARO-1 which was written by J. L. Jacocks and K. R. Kneile of the Arnold Engineering Development Center, Tullahoma, Tennessee. [1]* This code takes the finite volume approach in solving the three dimensional, unsteady Euler equations in cartesian coordinates via the explicit predictor-corrector algorithm credited to MacCormack. [2] Using this code as a starting point, the compressor is herein modeled in two dimensions, axial and circumferential, with the inertial grid "unwrapped" from about the compressor annulus to form a rectangular cartesian coordinate system. In modeling the compressor blading, the approach taken is essentially a semi-actuator disc method wherein two of the conservation partial differential equations are replaced by two algebraic constraint equations. Since the Euler equations inherently fail to account for the viscous phenomenon of rotating stall, an unsteady cascade loss model and an unsteady cascade deviation angle model were implemented.