Application of singular perturbation theory to compressible mass flow rate integration

A time efficient digital integration method for the solution of the orifice mass flow rate equations common in internal combustion engine breathing process simulation is discussed. Local linearization followed by development of a standard singular perturbation model is used to synthesize digital integrating factors that are applied to the original nonlinear differential equations. This approach results in a method suitable for high-speed flow rate integration over the entire flow rate operating range. Analytical development of the method and simulation results are summarized.<>