Heat Exchanger Control

Hot water is cooled in a tube-in-shell heat exchanger by cold water. The water comes from a 50 psig water header that provides water for three experiments in the laboratory. Some of the water is heated by an electrical heater before entering the heat exchanger. The temperature of the hot water leaving the heat exchanger is sensed and recorded. The control signal to the cold water valve is set from a personal computer using a data acquisition & control software package. All the test signals are generated by the computer, and data can be stored in the computer or on disks for further processing using LabView or MATLAB.

Control techniques studied:

  • Time-domain and frequency-domain system identification
  • Open-loop and closed-loop transfer function
  • Ultimate-gain and ultimate-frequency Ziegler-Nichols PI tuning