TABLE OF CONTENTS Psychrometry is the study of the properties of mixtures of air and water vapor. The subject is important in cooling system practice because atmospheric air is not completely dry but is a mixture of air and water vapor. In certain cooling systems, water is added to the air-water-vapor mixture. Psychrometric principals will be applied in this and later chapters to evaluate the performance of cooling towers, evaporative coolers, and systems incorporating adiabatic precooling of the air.
Since there is usually both a heat and mass transfer process between the air and some wetted surface, information on mass transfer is presented. Because of the analogy that exists between momentum, heat, and mass transfer, there is a similarity in the equations employed.
