Optimum control of heat exchangers with internal heat generation

This paper investigates the optimum control of a heat exchanger having internal heat sources from a reference steady state to a desired value. Both the wall and coolant are treated as distributed-parameter systems. Under certain constraints inherent in the operating conditions and physical limitations of the heat exchanger, the control function of the system, i.e. the heat generation rate which minimizes the deviation of the temperature distribution from an assigned pattern at a given time, is found through the use of a linear programming method. The effects of physical parameters on the optimal control function and the temperature response and distribution are examined. Experimental results are presented which compare favorably with the theoretical analysis. Heat exchangers to which these results apply include the electrical heater, a chemical reactor in which a chemical reaction occurs within the solid walls and a heterogeneous nuclear reactor.