Thermal Control*

Professor Mihir Sen
Department of Aerospace and Mechanical Engineering
University of Notre Dame
Notre Dame, IN 46556



University of Notre Dame chilled water and steam distribution system.

*Sponsored by D.K. Dorini (BRDG-TNDR), Organization of American States, National Autonomous University of Mexico, Kuwait University.


Overview


Heat transfer surfaces are susceptible to fouling and change in thermal characteristics. Artificial neural networks are a good way to learn, to adapt to changing circumstances, and to be able to control thermal systems. Techniques have been developed to obtain a network that is dynamically stable and that enables efficient temperature control (see figure below from Diaz, 2002). The control of a mathematical model of a heat exchanger is also reported. Networks deal with heat exchangers, piping, pumps and flow valves configured in the form of a network.

Experimental facilities

The experiments have been carried out in the Hydronics Laboratory in the Fitzpatrick Hall of Enginering. The laboratory facilities include the following.


Heat exchanger test facility: The photograph shows a wind tunnel in the rear, and in the foreground a water heater and a PC. A heat exchanger can be placed in the tunnel and measurements made of flow rates and temperatures. The PC is used to acquire and process data, as well as to provide control signals for manipulation.


Thermal control test loop: The photograph shows a cooling circuit with a primary loop that is cooled with chilled water from the building and three parallel secondary loops that use this water to cool heated water from electric heaters. A PC-based controller can be seen on the far right. Different control strategies can be used for each secondary loop and their performance compared.

Research

Research in thermal control is classified as below. Though a brief description is given of each, the details are left to the publications.

Theses and dissertations

Teaching