DIRECT CALCULATION OF WET-BULB TEMPERATURE AND DEW-POINT TEMPERATURE

A.K. SINGH¹, S. POONIA²*, D. JAIN³, D. SINGH^4
1ICAR-Central Arid Zone and Research Institute, Jodhpur, 342 003, Rajasthan, India
²ICAR-Central Arid Zone and Research Institute, Jodhpur, 342 003, Rajasthan, India
³ICAR-Central Arid Zone and Research Institute, Jodhpur, 342 003, Rajasthan, India
⁴School of Energy and Environmental Studies, Devi Ahliya Viswavidyalaya, Indore, 452001, Madhya Pradesh, India
* Corresponding Author : poonia.surendra@gmail.com

Received : 05-10-2019     Accepted : 26-10-2019     Published : 30-10-2019
Volume : 11     Issue : 20       Pages : 9169 - 9171
Int J Agr Sci 11.20 (2019):9169-9171

Keywords : Dry-bulb temperature, Wet-bulb temperature, Dew point temperature and Relative humidity
Academic Editor : Dr S. G. Savalia
Conflict of Interest : None declared
Acknowledgements/Funding : Authors are thankful to ICAR-Central Arid Zone and Research Institute, Jodhpur, 342 003, Rajasthan, India
Author Contribution : All authors equally contributed

Simple and precise methods for accurate calculation of wet –bulb temperature and dew-point temperatures are presented in the paper. Input parameters required for calculation of dew-point temperature and wet-bulb temperature are dry-bulb temperature and relative humidity. In this paper, the equations for determining dew point temperature for the entire pressure range are given. The equations proposed here for saturation vapour pressure for temperature range (0ºC to 110ºC) has an average error of 0.042% only and for temperature range (0ºC to -40ºC) error of 0.108% and the same equations can be rewritten to determine the value of dew-point temperature. The mean absolute deviation in calculated values of dew-point temperature was 0.04%. The proposed method for dew-point temperature led to an average error of 0.083%as compared to that of correct values. The mean absolute deviation in calculated values of wet-bulb temperature for the entire range (-40ºC to 110ºC) was 0.031ºC. The proposed method for wet-bulb temperature led to an average error of 0.09% as compared to that of correct values.

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