I am trying to calculate the rate (g/m(adsbygoogle = window.adsbygoogle || []).push({}); ^{2}) of water evaporation given Temperature, Humidity, Air Speed, elevation.

The best source of an equation for this I have found is from engineeringtoolbox.com, but I have found a possible error in their calculation. (I am in a far off land with no access to real textbooks)

The equation:

g = Θ A (xs - x) (1)

where

g = amount of evaporated water (kg/h)

Θ = (25 + 19 v) = evaporation coefficient(kg/m^{2}h)

However, later on the example switches air speed units:

g = ( 25 + 19(0.5 (m/s)) ) ( 25 (m) 20 (m) ) ( 0,019826 (kg/kg) - 0.0115 (kg/kg)) / 3600

= 0.04 kg/s

When I use this equation with m/s and kg/s, I get an inflated evaporation rate (their example alone provides and incredible evaporation rate for a pool).

Can anyone give me a confirmation of this equation?

Is there a more recommended equation for calculating evaporation(and a source)?

Thank you

:3

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# Evaporation of Water: Error in Formula?

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