Optimization of the efficiency of stall control using air injection for centrifugal compressors

Abstract

A plasticity theory for porous metals is proposed. A simple model of a porous materials is analysed by the finite element method. Small strain elastic–plastic analysis provides stress–strain curves, yield stressed and incremental plastic strain vectors for different void ratios. An assessment is made of an existing yield criterion for porous metals. A modified yield criterion and plastic potential function and, consequently, different plasticity equations are given. Reasonable agreement is obtained between the present numerical results and previous results in the literature.