2022 Annual Meeting
Phenomenological-Bases Model and Control Proposal for a Cooling Tower
Many manufacturing processes and most industrial chemical reactions generate heat that must be permanently removed in order to maintain standard operating parameters. Cooling towers filled with packing are commonly used to release excess heat loads from these processes, such as electric power generation units, thermal and nuclear power plants, chemical and petroleum industries and refrigeration and air-conditioning systems, into the atmosphere. A cooling tower is a heat and mass transfer device in which the two fluids, ambient air and warm water, are in direct contact with each other. This device uses evaporative heat and mass transfer to cool warm water. The water to be cooled is commonly distributed over a packing material into the tower. This causes the evaporation of a small portion of water, with a corresponding extraction of heat from the remaining water, while the air stream is humidified by picking up this moisture and some of the heat. The aim of this work is to enhance the performance of cooling process of water by using a model-based controller. The phenomenological-based semiphysical model is used as into the model-based controller. The performance of the model-based controller is contrasted with the performance of a common PID controller. The obtained results show that model-based control improves aspects of the process such as increasing the response speed of the system allowing it to operate at the desired final water temperature point, and avoiding undesired operating conditions in the tower, such as entrainment, channeling and dumping.