Psychrometric Properties: STD ATM
-21.0 100 to -30.0 100
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 | Pr da | Pr s | Ws kg kg (kg/kg) | cp da kJ kgK (kJ/(kg·K)) | cp s kJ kgK (kJ/(kg·K)) | dry bulb C (C) | hda kJ kg (kJ/kg) | hs kJ kg (kJ/kg) | lambda da W mK (W/(m·K)) | lambda s W mK (W/(m·K)) | mu da uPas (uPa·s) | mu s uPas (uPa·s) | nu da 1e6m2 s (1e-6 m2/s) | nu s 1e6m2 s (1e-6 m2/s) | relative humidity pct (%) | rho da kg m3 (kg/m3) | rho s kg m3 (kg/m3) | sda kJ kgdaK (kJ/(kg·K)) | ss kJ kgdaK (kJ/(kg·K)) | vda m3 kg (m3/kg) | vs m3 kg (m3/kg) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| STD ATM | -21.0 100 | 0.7143 | 0.7146 | 0.000579 | 1.0055 | 1.006 | -21 | -21.117 | -19.693 | 0.02273 | 0.02273 | 16.15 | 16.14 | 11.53 | 11.52 | 100 | 1.401 | 1.401 | -0.0804 | -0.0745 | 0.7137 | 0.7143 |
| STD ATM | -22.0 100 | 0.7145 | 0.7147 | 0.000525 | 1.0055 | 1.006 | -22 | -22.122 | -20.831 | 0.02265 | 0.02265 | 16.1 | 16.09 | 11.44 | 11.44 | 100 | 1.407 | 1.406 | -0.0844 | -0.079 | 0.7108 | 0.7114 |
| STD ATM | -23.0 100 | 0.7147 | 0.7149 | 0.000476 | 1.0055 | 1.0059 | -23 | -23.128 | -21.958 | 0.02258 | 0.02257 | 16.05 | 16.04 | 11.36 | 11.36 | 100 | 1.412 | 1.412 | -0.0884 | -0.0835 | 0.708 | 0.7085 |
| STD ATM | -24.0 100 | 0.7149 | 0.715 | 0.000431 | 1.0055 | 1.0059 | -24 | -24.133 | -23.074 | 0.0225 | 0.02249 | 15.99 | 15.99 | 11.28 | 11.28 | 100 | 1.418 | 1.418 | -0.0925 | -0.088 | 0.7051 | 0.7056 |
| STD ATM | -25.0 100 | 0.715 | 0.7152 | 0.000391 | 1.0055 | 1.0059 | -25 | -25.139 | -24.181 | 0.02242 | 0.02241 | 15.94 | 15.94 | 11.2 | 11.2 | 100 | 1.424 | 1.424 | -0.0965 | -0.0924 | 0.7023 | 0.7027 |
| STD ATM | -26.0 100 | 0.7152 | 0.7154 | 0.000353 | 1.0055 | 1.0058 | -26 | -26.144 | -25.278 | 0.02234 | 0.02234 | 15.89 | 15.89 | 11.11 | 11.11 | 100 | 1.43 | 1.429 | -0.1006 | -0.0969 | 0.6994 | 0.6998 |
| STD ATM | -27.0 100 | 0.7154 | 0.7155 | 0.000319 | 1.0055 | 1.0058 | -27 | -27.15 | -26.368 | 0.02226 | 0.02226 | 15.84 | 15.83 | 11.03 | 11.03 | 100 | 1.436 | 1.435 | -0.1047 | -0.1013 | 0.6966 | 0.697 |
| STD ATM | -28.0 100 | 0.7156 | 0.7157 | 0.000288 | 1.0055 | 1.0058 | -28 | -28.156 | -27.45 | 0.02218 | 0.02218 | 15.79 | 15.78 | 10.95 | 10.95 | 100 | 1.441 | 1.441 | -0.1088 | -0.1057 | 0.6938 | 0.6941 |
| STD ATM | -29.0 100 | 0.7158 | 0.7159 | 0.00026 | 1.0056 | 1.0058 | -29 | -29.161 | -28.525 | 0.0221 | 0.0221 | 15.73 | 15.73 | 10.87 | 10.87 | 100 | 1.447 | 1.447 | -0.1129 | -0.1101 | 0.6909 | 0.6912 |
| STD ATM | -30.0 100 | 0.716 | 0.7161 | 0.000235 | 1.0056 | 1.0058 | -30 | -30.167 | -29.593 | 0.02202 | 0.02202 | 15.68 | 15.68 | 10.79 | 10.79 | 100 | 1.453 | 1.453 | -0.117 | -0.1145 | 0.6881 | 0.6883 |
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