Digital simulation of nonlinear dynamic systems using standard FORTRAN

The capability to obtain either transient or equilibrium solutions for systems of mixed algebraic and differential equations, the latter independently of the stability of the system, is a useful tool for investigation of lumped thermo-dynamic models having unstable regimes of operation. A general-purpose simulation program giving these facilities is described. The program is written in standard Fortran to permit easy implementation on any computer. Its application is illustrated by reference to simulation of gas-turbine engines.