Abstract
An investigation of an analytical solution of the dynamics of a symmetrically operated parallel flow heat exchanger in the form of transfer matrix was performed. Perturbation method was used to linearize the usual non-linear model of such systems. A non-interactive controller to decouple the outputs and a controller to offset any expected disturbances in the boundary temperature was considered. A discrete model was established and found to predict the heat exchanger dynamics adequately. The results are acceptable and encouraging and the model has been found to be sufficient enough to achieve the objective of countering uncontrolled disturbance without requiring precise knowledge of process dynamics. The validity of the proposed control design is examined by comparing it with other models in the literature.