Hodgson, David A., authorDuff, William S., advisorYoung, Peter M., advisorOlsen, Daniel B., committee memberAnderson, Charles W., committee member2022-04-132022-04-132010https://hdl.handle.net/10217/234663Covers not scanned.Print version deaccessioned 2022.Cross-flow water-to-air heat exchangers are a common element in heating ventilating and air conditioning (HVAC) systems. In a typical configuration the outlet air temperature is controlled by the flow rate of water through the coil. In this configuration the heat exchanger exhibits non-linear dynamics. In particular the system has variable gain. Variable gain presents a challenge for the linear controllers that are typically used to control the outlet air temperature. To ensure stability over the entire operating range controllers need to be tuned at the highest gain state. This leads to sluggish response in lower gain states. Previous research has shown the use of steady state predictions of the flow rate needed to produce zero steady state error has improved the transient response of a heat exchanger. In this project a nonlinear controller that provides smooth mixing between steady state predictions and integral control was introduced. Bounds for the steady state error introduced by the controller were theoretically derived and experimentally verified. The controller outperformed a properly tuned nominal PI controller for both input tracking and disturbance rejection.doctoral dissertationsengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.Linear control systemsHeat exchangersText