Numerical Simulation of Rubber Curing Process for an Automotive Shock Absorber: Prediction of Optimal Curing Time and Experimental Validation

Accurate prediction of curing time is crucial for achieving optimal mechanical properties in rubber components, particularly in complex automotive parts produced via injection molding. This study employs ANSYS Fluent with a custom user-defined function (UDF) to simulate the vulcanization process of an automotive shock absorber, incorporating real compound properties derived from rheometric tests. The Kamal-Sourour kinetic model parameters were identified at ۱۴۰, ۱۵۰, and ۱۶۰◦C. Due to the low thermal diffusivity of rubber, significant temperature gradients develop during curing, leading to heterogeneous cure distribution. An optimized kinetic model with temperature-dependent reaction order n = aT ۲ + bT + c was developed, reducing prediction error from ۱۶.۳% (standard Kamal model) to ۹.۶% at ۱۵۵◦C. Numerical results, including temperature and cure state contours, demonstrate that surface regions cure faster while inner regions exhibit delayed induction but accelerated late-stage curing. The predicted optimal curing time of ۴۰۰ s deviates only ۴.۸% from the experimental value of ۴۲۰ s, obtained via mechanical stiffness measurements. The simulation accurately captures curing behavior without solving flow equations, offering substantial computational savings compared to full injection molding simulations.

کلیدواژه ها:

Rubber vulcanization ، Curing kinetics ، Kamal-Sourour model ، Rheometric test ، Non-isothermal curing ، Automotive shock absorber