Simple predictive tool to estimate relative humidity using wet bulb depression and dry bulb temperature

In this work, a simple predictive tool is presented to estimate relative humidity as a function of wet bulb depression and dry bulb temperature. The predictive tool is simple, straightforward, and can be readily implemented in any standard spreadsheet program leading to accurate, smooth, and non-oscillatory datapoints. The prime application of the method is as a quick-and-easy evaluation tool in conceptual development and scoping studies where the estimation of the relative humidity, as a function of wet bulb depression and temperature, is being considered. Results from the proposed correlation are successfully compared to available data in the literature for a wide range of wet bulb depression and dry bulb temperatures. This gives us the confidence to offer our findings for engineering applications where a rough and ready programmable estimate is sought.