Investigation of spatio-temporal behavior of coolant during the RHCM process

Abstract

Rapid Heat Cycle Molding (RHCM) is a new thermoplastic molding technology. The principle of this process consists in a rapid heating of the mold until a suitable temperature. After the filling stage, the cooling phase begins and continues until reaching the ejection temperature. And so on for the following RHCM cycles. In this paper, a three-dimensional numerical study of thermal behavior of RHCM mold for complex shaped automotive part production has been undertaken. Numerical simulations of heat transfer in cavity/core plates domains, polymer and coolant domains, in a cyclic transient regime, have been carried out. To do this, Gambit 2.3.16 has been used to generate the meshing and the commercial software Fluent 6.3.26 has been used to solve the CFD problem. The spatio-temporal behavior within horizontal and vertical channels has been studied. A progressive increase in the coolant temperature during its passage through the mold has been proved. As regard to the temperature at the outlet of the channels, a progressive decrease during the cooling phase has been demonstrated. Moreover, in this research work, we have highlighted the significance of the study of thermal behavior in the cooling water domain (contrary to the hypothesis which assumes a constant temperature of the coolant taken in previous researches) to provide accuracy of the predicted RHCM cycle.