Three issues in the design of an equation-based process simulator

Abstract: "An equation based process simulation program must address three major issues if it is to be useful to the practicing engineer: 1. The simulator must provide a graphical flowsheeting interface for convenient manipulation of equation and variables. 2. The simulator must support the user in developing a vaild problem specification, i.e., avoidance of structural singularities. 3. The simulator must recover gracefully from numerical singularities. We have developed a prototype simulator that addresses these issues. The first two capabilities have been implemented and a suggestion for the third is sketched."