Thermodynamic Model of Self-Heating Mold for the Energy Efficient Composite Manufacturing

Abstract

The method of out-of-autoclave manufacturing of the composite parts with the use of shape-generating molding tools with internal heating allows to abandon the usage of expensive and energy-consuming heating equipment. The thermodynamic model of unsteady heat transfer during molding of the polymeric composite material in the heated tools has been developed. The model allows obtaining the temperature distribution over the thickness of the system under study, evaluating the influence of the exothermic effect of the binder curing reaction, and determining the required power of the heating system. It is shown that energy saving for the heated fiberglass shape-generating molding tools is from 40 to 60%. Analysis of the influence of mechanical characteristics of the material of the molding tools on energy consumption has been carried out. Fiberglass has the lowest energy consumption; heating of the aluminum and steel tools of similar purpose will take 20% and 45% more power, accordingly. Dependencies of the heating system parameters on the various conditions of heat transfer (air circulation rate in the room and heating rate) are shown. The final stage of the study involved creating an experimental prototype of the portable heating equipment of the shape-generating molding tools for the manufacturing of structures of polymeric composite materials.