On-Line Fuzzy-Logic-Based Temperature Control of a Concentric-Tube Heat Exchanger Facility

Abstract

We have developed a fuzzy-rule-based controller to perform on-line temperature control of a concentric-tube heat exchanger facility. The rules for the controller were derived from dynamical values of the mass flow rates and fluid temperatures in the heat exchanger. The fuzzy controller was embedded in a closed-loop, single-input single-output system to control the outlet temperature of the cold fluid. The development of the controller was done in two phases, the difference between the phases being the information about the system that was used to build the corresponding control scheme. To validate this fuzzy controller, a series of experiments, corresponding to regulation and tracking of a setpoint, was carried out for maintaining specific values of the outlet temperature under different perturbations. Results from this investigation demonstrate that the fuzzy-rule-based controller is able to effect control of the system, and that the amount of information about the plant provided to it is important in terms of accuracy and efficiency.

Acknowledgments

Claudia Ruiz-Mercado and Luis Enrique Vilchiz have been recipients of a CONACyT Scholarship from Mexico for which we are grateful. Thanks to Dr. N. Petroff of Rehabilitation Institute at Chicago for his comments on the article. This work was partially supported by PROMEP/PTC-68, and by the FAI/UASLP research fund.