Gas thermal conductivity¶
Thermal conductivity of gas as a function of temperature can be calculated from the following equation:
where coefficients A, B, C, and D are obtained from tables in the Yaws’ Handbook
for inorganic and organic compounds. The k_gas_inorganic
function in the
Chemics package supports 259 gas species while the k_gas_organic
function supports 6,914 species. At a minimum, the functions require formula
name and temperature as input parameters; however, the CAS number is also needed
as an input if more than one form of a species exists.
Nomenclature¶
Source code¶

chemics.gas_thermal_conductivity.
k_gas_inorganic
(formula, temp, full=False)[source]¶ Thermal conductivity of gas as a function of temperature. Applicable to gas comprised of inorganic compounds. Results based on coefficients from Yaws’ Critical Property Data for Chemical Engineers and Chemists 1.
 Parameters
formula (string) – Molecular formula of the gas.
temp (float) – Temperature of the gas [K]
full (bool, optional) – When set to
False
(default) just thermal conductivity is returned. When set toTrue
then return thermal conductivity and other information.
 Returns
k_gas (float) – Thermal conductivity of gas [W/(m K)]
k_gas, cas, tmin, tmax, a, b, c, d (tuple) – Additional values are only returned when keyword
full=True
.k_gas  Thermal conductivity of gas [W/(m K)]cas  CAS number []tmin, tmax  Temperature range at which results are applicable [K]a, b, c, d  Values for regression coefficients []
 Raises
ValueError – If gas formula is not found in csv data file.
ValueError – If gas temperature is not in range between tmin and tmax.
Examples
>>> k_gas_inorganic('N2', 773) 0.0535
>>> k_gas_inorganic('N2', 773, full=True) (0.0535, '7727379', 63.15, 1500.0, 0.0002267, 0.0001027, 6.0151e08, 2.2331e11)
References
 1
Carl L. Yaws. Table 84. Thermal Conductivity of Gas – Inorganic Compounds in Yaws’ Critical Property Data for Chemical Engineers and Chemists. Published by Knovel, 2014.

chemics.gas_thermal_conductivity.
k_gas_organic
(formula, temp, cas=None, full=False)[source]¶ Thermal conductivity of gas as a function of temperature. Applicable to gas comprised of organic compounds. Results based on coefficients from Yaws’ Critical Property Data for Chemical Engineers and Chemists 2.
 Parameters
formula (string) – Molecular formula of the gas.
temp (float) – Temperature of the gas [K]
cas (string) – CAS number of the gas, required for some species []
full (bool, optional) – When set to
False
(default) just thermal conductivity is returned. When set toTrue
then return thermal conductivity and other information.
 Returns
k_gas (float) – Thermal conductivity of gas [W/(m K)]
k_gas, cas, tmin, tmax, a, b, c, d (tuple) – Additional values are only returned when keyword
full=True
.k_gas  Thermal conductivity of gas [W/(m K)]cas  CAS number []tmin, tmax  Temperature range at which results are applicable [K]a, b, c, d  Values for regression coefficients []
 Raises
ValueError – If gas formula is not available in CSV data file.
ValueError – If multiple substances have same formula. Require CAS number.
ValueError – If gas temperature is not in range between Tmin and Tmax.
Examples
>>> k_gas_organic('CO', 801) 0.05722
>>> k_gas_organic('C18H38O', 920, cas='593328') 0.04174
References
 2
Carl L. Yaws. Table 85. Thermal Conductivity of Gas – Organic Compounds in Yaws’ Critical Property Data for Chemical Engineers and Chemists. Published by Knovel, 2014.