Discussion Forum
 • Materials • Design Center • Processes • Units & Constants • Formulas • Mathematics
 Home Membership Magazines Forum Search Member Calculators
 Materials Design Processes Units Formulas Math
List Recent Topics | Start a New Topic

Message No. 13893, Started by devitg on 05/11/04
 water steam pressure in ambient air Talking about psichrometry Given T in Kelvin or absolute temp For Pws [presure water steam] Is this formula valid ? for Water air from 0 to 200 C degree ln Pws= a/t + b+c*t+d*t^2+e*t^3+f*lnT for the followings values a      -5800.2206 b      -5.5162256 c      -0.048640239 d      4.18E-05 e      -1.45E-08 f       6.5459673 I used it for 100 C dgree and give p mbar      1014.217979 mbar , that is a normal atmospheric pressure My concern is if it is valid for the air ambient temperature I wan to calc the Relative humidity by reading the DryBulb and WETbulb  temperature. I have 2 data loggers and  I modify one of them to read wet bulb temperature, so I can charge the data from it to a spread sheet and get the HR %  . maybe it is not a conventional way of doing , but is it what I have and will have  for ever. (lack of money to buy a HR datalogger) Hope you can give me any advice. PS I have the spread sheet done.
Reply | Start a New Topic | List Recent Topics

Follow-up Messages (1)
 If I understand you correctly, you want to confirm the validity of your equ... No. 13895, Posted by mbeychok on 05/11/04, 10:29 PST.