S. K. Padmanabhan

Research Project

Stochastic Modeling of Resin Transfer Molding

Resin Transfer Molding (RTM) is a fabrication process that offers the potential to manufacture reinforced thermosetting composite materials of complex geometries cost-effectively, and at high throughputs. RTM consists of filling a fibrous preform, shaped to the form of the desired product, with a resin-catalyst mixture. Strong uncertainties inherent in the process, however, lead to appreciable variablities in the quality of composites manufactured via this route. Although a number of RTM process models have already been developed over the years, a systematic analysis of the associated parameter uncertainties has not been conducted.This research is to identify the effects of process and material parameter uncertainties on the isothermal and nonisothermal variants of RTM processes. The first phase of the research concentrated on the quantification of the process variabilites in the isothermal mold filling of a rectangular mold. The next step was to study the effects of the uncertainties on the isothermal cure of resin systems separately, and to determine the optimal isothermal temperatures. A detailed stochastic modeling methodology is being conducted currently in order to determine the combined effects of the uncertainties in the fluid mechanics and the reaction kinetics of the resin on nonisothermal mold filling.

Publications

1. S. K. Padmanabhan and R. Pitchumani, "Stochastic Analysis of the Resin Transfer Molding Process," in Proceedings, 12th Tech. Conf. Amer. Soc. for Composites, R. Gibson, G. Newaz, eds., pp. 797-806, 1997.
2. S. K. Padmanabhan and R. Pitchumani, "Effects of Process Parameter Uncertainties on Nonisothermal Mold Filling During RTM," Proceedings of the International SAMPE Symposium and Exhibition, 43(2), pp. 1275-1288, 1998.
3. S. K. Padmanabhan and R. Pitchumani, "Stochastic Analysis of Isothermal Cure of Resin Systems," Polymer Composites, 20(1), 72-85, 1999.
4. S. K. Padmanabhan and R. Pitchumani, "Stochastic Modeling of Nonisothermal Flow During Resin Transfer Molding Processes," International Journal of Heat and Mass Transfer, 42(16), 3057-3070, 1999.