Ecologically and economically conscious design of the injected pultrusion process via multi-objective optimization

• Published in: Modelling and simulation in materials science and engineering Vol. 12; no. 3; pp. S205 - S219
• Main Authors: Srinivasagupta, Deepak, Kardos, John L
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.05.2004
• ISSN: 0965-0393; 1361-651X
• DOI: 10.1088/0965-0393/12/3/S10

Injected pultrusion (IP) is an environmentally benign continuous process for low-cost manufacture of prismatic polymer composites. IP has been of recent regulatory interest as an option to achieve significant vapour emissions reduction. This work describes the design of the IP process with multiple design objectives. In our previous work (Srinivasagupta D et al 2003 J. Compos. Mater at press), an algorithm for economic design using a validated three-dimensional physical model of the IP process was developed, subject to controllability considerations. In this work, this algorithm was used in a multi-objective optimization approach to simultaneously meet economic, quality related, and environmental objectives. The retrofit design of a bench-scale set-up was considered, and the concept of energy loss in the process, as well as in vapour emission, was introduced. The multi-objective approach was able to determine the optimal values of the processing parameters such as heating zone temperatures and resin injection pressure, as well as the equipment specifications (die dimensions, heater, puller and pump ratings) that satisfy the various objectives in a weighted sense, and result in enhanced throughput rates. The economic objective did not coincide with the environmental objective, and a compromise became necessary. It was seen that most of the energy loss is in the conversion of electric power into process heating. Vapour energy loss was observed to be negligible for the most part.