Real-Time Temperature Control of Shell and Tube Heat Exchanger by IMC based PID controller

Abstract

Shell and Tube Heat Exchanger is most widely used and most efficient heat exchanger in industries. The outlet temperature of the shell and tube heat exchanger system has to be kept at a desired set point according to the process requirement by using controllers. Many controllers such as PID, feedback plus feed forward, Fuzzy logic, Internal Model based PID controller are used to control the temperature. The control system objective is to control the hot fluid outlet temperature by manipulating the inlet cold fluid flow rate. The transfer function of the shell and tube heat exchanger process is obtained using energy balance equations. Designing of the PID Controller is done by conventional Cohen-Coon tuning method and advanced IMC method. The closed loop results are obtained using PID controller both Cohen-Coon method and IMC method. The closed loop responses for various set point changes in hot fluid outlet temperature and disturbance in inlet temperature of cold fluid are studied. The experiment and MATLAB simulations are carried out by using the above parameters of CC-PID and IMC-PID and the data are noted for different set points. Comparison is made between the results of both the experiment and simulations. And the compared the results of Cohen-Coon method and IMC tuning method. On comparing the results, we can demonstrate that IMC based PID controller gives better responses in terms of lesser overshoot and faster settling time. The present work emphasis is about the experimental demonstration of advanced controller such as Internal model controller (IMC) to a general process such as shell and tube heat exchanger control.