A new theoretical formulation of dew point temperatures applicable for comfort air-cooling systems

Abstract

Dew point temperature (DPT) of moist air plays a key role in ascertaining the comfort condition as well as indoor air quality for built environments. This article outlines a simple method to transform the fundamental relation between saturation pressure and temperature into a concise mathematical form for dew point temperatures of moist air that is applicable for normal comfort air conditioning systems. The error between the results from the derived equation and the ASHRAE correlation is found to be well within the accuracy limits of commonly used climatic sensors. Based on this equation, a simple computational method for wet bulb temperature (WBT) is proposed. The results from this method show minuscule error in comparison with the standard psychrometric data. Also, the DPT equation is used as a basis for plotting wet sensible and latent loads of a cooling dehumidifying coil by applying both temperature and humidity discretization schemes. Application of the inherently simple and aptly accurate DPT equation results in the representation of subtle variations in coil loads at varying psychrometric parameters of moist air, to be conclusive and theoretically conformal.