A dynamic model of a centrifugal compressor capable of system simulation in the virtual test bed (VTB) computational environment is presented. The model is based on first principles, i.e. the dynamic performance including the losses is determined from the compressor geometry and not from the experimentally determined characteristic performance curves. In this study, the compressor losses, such as incidence and friction losses, etc., are mathematically modeled for developing compressor characteristics. For easy implementation in the VTB platform, the non-linear governing equations are discretized in resistive companion (RC) form. The developed simulation model can be applied to virtually any centrifugal compressor. By interfacing with a composite system, such as a Brayton cycle gas turbine, or a fuel cell, the compressor dynamic performance can be evaluated. The surge line for the compressor can also be determined from the simulation results. Furthermore, the model presented here provides a valuable tool for evaluating the system performance as a function of various operating parameters. (c) 2005 Elsevier B.V. All rights reserved.