Simulateur modulaire séquentiel à convergence simultanée

Abstract

This paper is concerned with the introduction into a conventional sequential modular flowsheeting program of a general non-linear equation-solving algorithm for efficiently performing simulation and design problems. The equations resulting from internal recycling streams and from design specifications are solved simultaneously. Convergence properties of various numerical methods are demonstrated by examples. Test results indicate that Broyden's method is effective if special care is taken in estimating the initial matrix. The use of the identity matrix often involves oscillatory behaviour of the global convergence. An alternative procedure for estimating the jacobian matrix is proposed. This procedure provides the optimum performance and avoids the costly generation of a full jacobian matrix by finite-difference calculations. All tests in this study were performed using the flowsheeting program PROSIM.