Predicting water content of compressed air

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Publication details

Bahadori, A & Mokhatab, S 2008, 'Predicting water content of compressed air', Chemical Engineering, vol. 115, no. 9, pp. 56-57.

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It is necessary to be able to predict the water content of air and saturated air to design and apply the appropriate type of drying to the compressed air system. Relative humidity and dew point are the two methods of indicating the amount of moisture in theair. Equation (1) presented a new correlation in which four coefficients were used to correlate water content, W, and either the relative humidity (RH) or the absolute pressure. The Water content, W, in Equation (1) was given as millimeters of water per cubic meter of air, while the variable X is either the relative humidity, or, for saturated air condition, X is the absolute pressure, which can range from 100 to 1,400 kPa. T is the temperature for K for Equations (2) to (5), and the 'tuned' coefficients are obtained by a least-squares analysis of data. The experiments found that the higher the temperature, the greater is air's capacity to hold water vapor, while increasing pressure reduces the ability of air to hold moisture.