LAUSR

A cooling tower (CT) model was built based on physical thermodynamics and heat and mass transfer principles using the effectiveness-NTU method for heat exchanger performance. The focus of the model was to use non-intrusive measurements and predict the exiting water temperature from the cooling tower given certain inputs. Compared with the existing models, the new model has two main advantages: (1) the model involves only the key important non-intrusive input variables and has an intuitive description of the CT operation; (2) it is modular and can be used as an input to other models to perform overall cooling plant optimization. The focus of the modeling was not to get the most accurate measurements, but rather to help in the aid of developing a system level cooling tower model which could be used as a part of an optimization framework for overall building energy consumption. The model still predicted the results accurately within 8% when compared with the results from field experiments. During steady-state operation, the results were even stronger with mean absolute percentage error within 5%. Model validation is performed at various ambient conditions and the results are supported with data from a hospital building in Alcorcon, Spain.