PEJ
14-10-2008, 11:45 AM
Apologies first of all if this is the wrong place to post this question but here it is.
I am looking at a technical paper that states that the "vapour pressure of air in millibars" at 20C and 60% RH is 14.15.
And another article that says "With an air temperature of 25C and 50% relative humidity, the humidity ratio in the air is 0.0115 kg/kg"
Where do they get this information from? Is it from a mollier diagram? The only one I can reference does not have a scale in millibars and the humidity ratio looks more like 0.0095 to me.
Am I looking in the wrong place? Where can I find the vapour pressure of air at various temps and RHs?
I am looking at a technical paper that states that the "vapour pressure of air in millibars" at 20C and 60% RH is 14.15.
And another article that says "With an air temperature of 25C and 50% relative humidity, the humidity ratio in the air is 0.0115 kg/kg"
Where do they get this information from? Is it from a mollier diagram? The only one I can reference does not have a scale in millibars and the humidity ratio looks more like 0.0095 to me.
Am I looking in the wrong place? Where can I find the vapour pressure of air at various temps and RHs?