Looking for more than a boil off calculator.

Anyone know of a source for a Evaporation Rate Estimation claculator?

I have tried a google search using several differing terms but have not found what I am looking for.

I want to be able to key a water temp, air temp, humidity, and water volume and calculate the potential / estimated loss over time. this is something that Boil Off calculators can not so given that none that I have seen include for a variable humidity. At best, they calculate for how much "extra" water to have on hand from a known "rate per hour" or "percentage per hour".

If no existing calculator exists, anyone know how to make one in excel (meaning, what would the formulae be)?

Example;

User enter Current Air temp and Relative Humidty (taken from a outdoor device). And the water volume (or surface area) and temp (boiling being the default). And the result would be the volume amount of water loss per hour at the given humidity.

I recognize that air movement is stiull a factor and that boil temp varies by elevation. Perhaps these could be included if know.

Then, this number could be used to better drive our brewday softwares.

1. Learn Thermodynamics and Psychrometrics
2. Study a Mollier Diagram
3. Apply newly found knowledge

Psychrometrics - Wikipedia, the free encyclopedia

I don't know a formula but you'll also need to know the amount of BTU's you are effectively getting into the boil, as well as air movement. The more heat you put into the kettle the more will boil off (since it won't go any higher than 212 in temp).