Temperature Versus Relative Humidity
Links to curves that plot the relationship. February 26, 2005
1. I have been looking for a chart that will tell me how much the RH will decrease for a given rise in temperature.
2. Can a wet/dry thermometer give false readings even with some air flow across the bulb?
(Sawing and Drying Forum)
There is a very useful psychometric chart in most of the kiln publications (including the Kiln Operator's Handbook, which I believe is available online through USDA/USFS), which shows the relationship between RH/DB/WB temperatures.
It should be hanging on the wall of every kiln control room to provide a better understanding of how kiln schedules work, and to allow you to make decisions about changing one of these factors.
helps me understand RH. It has a table of saturation vapour pressure. The vapour pressure divided with the saturation pressure is the RH. If temperature increases, the saturation vapour pressure increases, decreasing the RH.
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