Clasius-Clapeyron equation for water vapor
Input(s)
\(L_{v}\): Heat of Vaporization of one mole of Liquid \((\mathrm{J} / \mathrm{mol})\)
\(\mathrm{T}_{1}\): Absolute Temperature of Condition \(1\left({ }^{\circ} \mathrm{F}\right)\)
\(\mathrm{T}_{2}\): Absolute Temperature of Condition \(2\left({ }^{\circ} \mathrm{F}\right)\)
\(R\): Gas Constant for Water Vapor \(\left(\mathrm{psi} / \mathrm{mol}^{\circ} \mathrm{F} \mathrm{s}{ }^{2}\right)\)
Output(s)
\(p_{v 1}\): Vapor Pressure at the Temperature \(\mathrm{T}_{1}(\mathrm{psi})\)
\(p_{v 2}\): Vapor Pressure at the Temperature \(\mathrm{T}_{2}(\mathrm{psi})\)
Formula(s)
\[
\ln \left(\frac{\mathrm{p}_{\mathrm{v} 1}}{\mathrm{p}_{\mathrm{v} 2}}\right)=\frac{\mathrm{L}_{\mathrm{v}}}{\mathrm{R}}\left(\frac{1}{\mathrm{~T}_{1}}-\frac{1}{\mathrm{~T}_{2}}\right)
\]
Reference(s)
McCain Jr, W. D. (1990). Properties of Petroleum Fluids. PennWell Corporation. Page: 54.