TP22-28: Two and Two does not Always Equal Four: Achieving Consistency in Cooling Tower Design

Some aspects of evaporative cooling tower design have changed considerably over decades while others have not. Calculation is an area that has seen much change, especially with the advent of computers. Some calculation approaches follow earlier graphical procedures, but many do not. Consistency is essential—from design to performance to testing—in order to assure value, equity, accuracy, and protection against liability. Consistency requires clear and precise definitions plus comprehensive understanding, but not rigid uniformity. If fill characteristics developed for one method are used in a different calculation method, errors may result. If test results are corrected using performance curves not applicable to the operating conditions during the test, the evaluation may be meaningless and the effort wasted. In this paper, we consider those details necessary to achieve the goal of consistency—from start to finish. This is followed by a Historical Design narrative that traces the evolution of cooling tower design methods and highlights the contributions made by various people.