Is there a formula for calculating the evaporation of water on dry land?
I have pigs and during the summer they get hot. I've tried misters and timer controlled sprinklers but neither suited my needs, the pigs either got ahold of the mister line and ripped it down or i just forgot to head out and turn it on and off, and the sprinkler on a timer was never right, on hot days it underwatered leaving the pen dry and dusty which is unpleasent for the pigs and on cold days it overwatered leaving the pen a muddy mess which was also unpleasant for the pigs (contrary to popular belief pigs actually don't like mud its just something cool for them to roll in and natural sunscreen. Pigs would much rather have clear water raining down on them). I decided I'm going to make a simple Arduino controlled pig sprinkler. I'm going to equip it with a temperature and humidity sensor and I want it to plug the data it gets into a formula which calculates how long it will take for the water to evaporate, it will then take that data and use it to calculate the time in between sprinkler runs. But the obvious dilemma here is I cant seem to find a formula which will work. Any help is greatly appreciated! Thanks a bunch.