THERMAL ANALYSIS OF ROTATIONAL MOULDING PROCESS: AN APPLICATION TO MULTILAYER MOULDING
Keywords:
LLDPE, PA-11, Heaviside FunctionAbstract
Rotational Moulding is one of the fastest growing technologies in the processing of thermo-plastics. Multilayer products obtained by this process find extensive application in automobile components, particularly in fuel tanks. The process is characterized by a complex nature of heat transfer involving several phase changes. This paper presents a transient thermal simulation of the process for multilayer moulding of Linear Low Density Polyethylene (LLDPE) and Polyamide -11 (PA-11). FEM based COMSOL software is used for analysis and Heaviside function is used to model the phase changes over a range of temperatures. The cycle time, time required for phase transitions, time required for optimal curing temperature and demoulding time have been found out. It takes approximately 66 minutes to complete the cycle. The study can be useful to rightly tune the process to achieve the optimal quality characteristics of the part with reduced energy consumption.
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