Prediction of process parameters for intelligent control of tunnel freezers using simulation

Mathematical modeling and simulation of cryogenic tunnel freezers

“…A simulation based feedforward strategy has been proposed by Ramakrishnan et al (2004). However, a model predictive control strategy that integrates feed-forward and feedback strategies has been shown to be more effective (Shaikh & Prabhu, 2002).…”

“…The assumption made while using this approach is that a controller (with the control objective of maintaining the temperature profile constant) is used in the freezing tunnel, which in general is true (Ramakrishnan et al, 2004). The heat lost by the food product as it travels through the tunnel freezer is given by Eq.…”

“…The setup cost of a cryogenic freezing system is approximately one-fourth of the cost of its mechanical counterpart; however, the operating costs are almost eight times as much (Ramakrishnan, Wysk, & Prabhu, 2004). Current industrial controllers use programmable logic controllers (PLCs) for regulating the belt speed of the tunnel freezers, which leads to conservative set-points and consequently significant operational cost and frequent over-freezing.…”

Model predictive controller for cryogenic tunnel freezers

“…• The sensitivity of the control algorithm varies with the input temperature, shape, size and type of food due to the nonlinear character of the freezing process. Ramakrishnan et al (2004), reported further improvement in the control algorithm for cryogenic tunnel freezers by using a feed-forward control strategy. The control algorithm discussed by them involves the continuous monitoring of product input and controlling either or both of the refrigerant flow and conveyor speed.…”

“…Other advantages of using this technology in the food industry can be summarized as follows (Awonorin, 1997;Ramakrishnan, Wysk, & Prabhu, 2004):…”