Miscellaneous Problems

Abstract

1. The temperature of a plastic moulding process is controlled by heating the jacket surrounding the plastic charge (fig. 9.1). The proportional controller supplies heat equal to B times the temperature error (in K) at the jacket. The jacket temperature changes by 2 × 10⁻⁶ K J⁻¹ of heat supplied or extracted. The temperature C of the plastic charge changes by 0.004 (K s⁻¹)/K temperature difference from the jacket. The temperature difference in the jacket may be assumed uniform.