Dew point change with increase in pressure and decrease in temperature
Dew point change with increase in pressure and decrease in temperature
(OP)
Hi everyone,
Hope I am posting in the right forum. I had a question about dew point and, since this is not my field, I am somewhat lost. I am trying to find out what happens to the dew point of a saturated gas under vacuum when the temperature drops by 20 deg F and the pressure increases to 5 psig. Any guidance on this issue would be much appreciated.
Thank you,
vroma
Hope I am posting in the right forum. I had a question about dew point and, since this is not my field, I am somewhat lost. I am trying to find out what happens to the dew point of a saturated gas under vacuum when the temperature drops by 20 deg F and the pressure increases to 5 psig. Any guidance on this issue would be much appreciated.
Thank you,
vroma





RE: Dew point change with increase in pressure and decrease in temperature
RE: Dew point change with increase in pressure and decrease in temperature
Thanks.
RE: Dew point change with increase in pressure and decrease in temperature
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RE: Dew point change with increase in pressure and decrease in temperature
RE: Dew point change with increase in pressure and decrease in temperature
"a saturated gas under vacuum"
Sounds like a contradiction in terms to me...
"when the temperature drops by 20 deg F and the pressure increases to 5 psig"
A rise in pressure is usually accompanied by a rise in temperature instead of a drop in temperature.
If in your system the temperature drops while pressure is raised, then extra gas has been added to the system, otherwise this can not be true.
RE: Dew point change with increase in pressure and decrease in temperature
RE: Dew point change with increase in pressure and decrease in temperature
RE: Dew point change with increase in pressure and decrease in temperature
RE: Dew point change with increase in pressure and decrease in temperature
http://www.phymetrix.com/Software.htm
RE: Dew point change with increase in pressure and decrease in temperature
your question is about dew point, and the dew point is the temperature to which a given parcel of air must be cooled, at constant barometric pressure, for water vapor to condense into water. The condensed water is called dew. The dew point is a saturation point.
Further to this, i believe that your question is about air (moist air)...
there is a relation to find out the dew-point....
If your gas at the lower tempeature is also saturated... (which i think it would be) ... the dew point will be the same ... cuz at saturation the dew point is equal to the temperature itself.
If your gas at lower temperature is not saturated, then you need one more parameter from any of these to calculate dew-point.
Relative humidity, degree of saturation, enthalpy, humidity ratio, specific volume, density, vapour pressure ...etc.
Pressure does changes the solubility of gas.... but for each pressure there is a different data sets for each of these parameters. sp increase in pressure isnt sufficient enough to calculate the new dew point. I'll tell you how to calucalte this if you tell me what are the conditions of gas before and after. And what gas is this
RE: Dew point change with increase in pressure and decrease in temperature
http://en.wikipedia.org/wiki/Dew_point
RE: Dew point change with increase in pressure and decrease in temperature