Psychrometric Properties: STD ATM
20.0 10 to 20.0 90
Psychrometric properties of moist air — humidity ratio, enthalpy, dew point, wet-bulb temperature, and specific volume as functions of dry-bulb temperature and relative humidity; also includes saturation thermodynamic and transport properties (viscosity, thermal conductivity, Prandtl number, density) from ASHRAE 2021 tabulated data
| pressure condition | lookup key | dew point C (C) | dry bulb C (C) | enthalpy kJ kg (kJ/kg) | humidity ratio kg kg (kg/kg) | relative humidity pct (%) | specific volume m3 kg (m3/kg) | standard | wet bulb C (C) |
|---|---|---|---|---|---|---|---|---|---|
| STD ATM | 20.0 10 | -12.56 | 20 | 23.772 | 0.001439 | 10 | 0.8324 | ASHRAE Fundamentals 2017 Ch.1 | 6.96 |
| STD ATM | 20.0 100 | 20.04 | 20 | 57.419 | 0.014695 | 100 | 0.8501 | ASHRAE Fundamentals 2017 Ch.1 | 20.01 |
| STD ATM | 20.0 20 | -3.63 | 20 | 27.441 | 0.002884 | 20 | 0.8343 | ASHRAE Fundamentals 2017 Ch.1 | 9.1 |
| STD ATM | 20.0 30 | 1.92 | 20 | 31.128 | 0.004337 | 30 | 0.8363 | ASHRAE Fundamentals 2017 Ch.1 | 10.82 |
| STD ATM | 20.0 40 | 6.02 | 20 | 34.831 | 0.005796 | 40 | 0.8382 | ASHRAE Fundamentals 2017 Ch.1 | 12.32 |
| STD ATM | 20.0 50 | 9.3 | 20 | 38.552 | 0.007262 | 50 | 0.8402 | ASHRAE Fundamentals 2017 Ch.1 | 13.7 |
| STD ATM | 20.0 60 | 12.03 | 20 | 42.29 | 0.008734 | 60 | 0.8421 | ASHRAE Fundamentals 2017 Ch.1 | 15.01 |
| STD ATM | 20.0 70 | 14.4 | 20 | 46.046 | 0.010214 | 70 | 0.8441 | ASHRAE Fundamentals 2017 Ch.1 | 16.28 |
| STD ATM | 20.0 80 | 16.48 | 20 | 49.819 | 0.011701 | 80 | 0.8461 | ASHRAE Fundamentals 2017 Ch.1 | 17.53 |
| STD ATM | 20.0 90 | 18.35 | 20 | 53.61 | 0.013194 | 90 | 0.8481 | ASHRAE Fundamentals 2017 Ch.1 | 18.77 |
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