Class: `Gas`

Description

The Gas class represents the properties and constants for a generic gas mixture.
It provides physical and thermodynamic properties required in process engineering simulations and calculations.
This class is typically used as a placeholder or for defining user-specified gases in simulations.

Properties

name (string): Gas
formula (string): N/A (mixture or undefined)
molecular_weight (float): class attribute, default 28.0 g/mol; set it on the instance to change it

Class Reference

class Gas()

Parameters:
* temperature: Temperature, default = Temperature(25,"C")
* pressure: Pressure, default = Pressure(1,"atm")
* density: Density, default = None
* specific_heat: SpecificHeat, default = None
* viscosity: Viscosity, default = None
* thermal_conductivity: ThermalConductivity, default = None
* vapor_pressure: Pressure, default = None
* enthalpy: HeatOfVaporization, default = None

Methods

The properties of the Gas class are calculated using the following methods, inherited from the base Component class.

phase(): Always "gas" under standard simulation conditions.
density(): Uses the Ideal Gas Law with user-provided molecular weight.
specific_heat(): User-defined or estimated based on empirical correlations.
viscosity(): Uses Sutherland’s Law or user input.
thermal_conductivity(): User-defined or estimated with polynomial correlation.
vapor_pressure(): Not typically applicable for gas mixtures (default = None).
enthalpy(): Estimated from heat capacity correlation and integration over temperature range.

Examples

from processpi.components import Gas
from processpi.units import *

# Define a gas with approximate molecular weight (example: Nitrogen ~28.0 g/mol)
custom_gas = Gas(temperature=Temperature(25, "C"), pressure=Pressure(1, "atm"))
custom_gas.molecular_weight = 28.0

print(custom_gas.density().to("kg/m3"))
print(custom_gas.viscosity().to("Pa·s"))
print(custom_gas.specific_heat().to("J/kgK"))
print(custom_gas.thermal_conductivity().to("W/mK"))
print(custom_gas.enthalpy().to("J/kg"))

Class: Gas