Functional requirements of a simulation software for liquid molding processes

Numerical simulation of liquid molding processes such as RTM ("Resin Transfer Molding") and SRIM ("Structural Reaction Injection Molding") is becoming more important as the cost of industrial molds increases with complexity of molded parts. Based on five years of laboratory and field experience, a simulation software called RTMFLOT has been developed at the Center for Applied Research on Polymers of Ecole Polytechnique de Montreal, Canada. The aim of this article is to examine the functional requirements for an effective computer simulation of liquid molding processes. These requirements can be divided in three parts: general, when they apply to any mold filling simulation; specific, when they are related to flows in porous media; and practical, when they concern the computer implementation of the filling algorithm. The particular features of the simulation software RTMFLOT will be described here in order to illustrate these general con-cepts. Validation results for parts with irregular boundaries, inserts or ribs are also presented. Finally, current research on multilayer filling and non-isothermal liquid composite molding is discussed.