Psychrometric Properties: STD ATM
40.0 10 to 40.0 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 | 40.0 10 | 2.64 | 40 | 51.998 | 0.004565 | 10 | 0.8936 | ASHRAE Fundamentals 2017 Ch.1 | 18.51 |
| STD ATM | 40.0 100 | 40.02 | 40 | 166.132 | 0.048883 | 100 | 0.9568 | ASHRAE Fundamentals 2017 Ch.1 | 40.15 |
| STD ATM | 40.0 20 | 12.81 | 40 | 63.929 | 0.009198 | 20 | 0.9002 | ASHRAE Fundamentals 2017 Ch.1 | 22.7 |
| STD ATM | 40.0 30 | 19.16 | 40 | 76.038 | 0.0139 | 30 | 0.9069 | ASHRAE Fundamentals 2017 Ch.1 | 25.92 |
| STD ATM | 40.0 40 | 23.86 | 40 | 88.329 | 0.018672 | 40 | 0.9138 | ASHRAE Fundamentals 2017 Ch.1 | 28.58 |
| STD ATM | 40.0 50 | 27.62 | 40 | 100.806 | 0.023517 | 50 | 0.9207 | ASHRAE Fundamentals 2017 Ch.1 | 30.89 |
| STD ATM | 40.0 60 | 30.78 | 40 | 113.473 | 0.028436 | 60 | 0.9277 | ASHRAE Fundamentals 2017 Ch.1 | 32.98 |
| STD ATM | 40.0 70 | 33.5 | 40 | 126.335 | 0.03343 | 70 | 0.9348 | ASHRAE Fundamentals 2017 Ch.1 | 34.91 |
| STD ATM | 40.0 80 | 35.91 | 40 | 139.395 | 0.038501 | 80 | 0.942 | ASHRAE Fundamentals 2017 Ch.1 | 36.73 |
| STD ATM | 40.0 90 | 38.07 | 40 | 152.659 | 0.043651 | 90 | 0.9494 | ASHRAE Fundamentals 2017 Ch.1 | 38.47 |
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