Today, time available for production development is shorter and good quality development is required. Using the finite element method is a mean of meeting this requirement. This method of analysis is very adaptable to many fields and can predict static stress, strength, endurance, resonance, dynamic stress, thermal conductivity, convection, radiation, the optimum design, sound, fluid behavior, and electromagnetics in a short period. Furthermore, finite element methods are becoming more practical because of increased speed by computer vector operations and the main memory expansion of computers.
This paper outlines an analytical model for studying vibration characteristics including amplitude, modal shapes and stress while a variable displacement compressor is operating. Finite element analysis reveals the dynamic behavior of the mounts and body of this compressor. This dynamic behavior analysis is based on the shaft bearing load which is subjected to unsteady forces, calculated beforehand by dynamic behavior simulation. Based on these loads, eigenvalues and frequency responses, transient dynamic analysis is conducted using simultaneous inverse iteration and the Householder/QR methods. (See flow chart.)