PyFluids

A simple, full-featured, lightweight CoolProp wrapper for Python.

Installation

The project gets published on PyPI as pyfluids. For install the latest version using pip:

pip install pyfluids

Quick start

All calculations of thermophysical properties are performed in SI units.

The Fluid class is responsible for pure fluids and binary mixtures, the Mixture class - for mixtures with pure fluids components, the HumidAir class - for humid air.

For Fluid use PureFluids, IncompPureFluids, IncompMixturesMF, IncompMixturesVF enums. For Mixture - list of PureFluids.

To update the fluid state use Input enum (for Fluid and Mixture) or HAInput (for HumidAir) enum and their with_value method (always).

You can also convert an instance of Fluid, Mixture or HumidAir to a JSON string or dictionary using methods to_json and to_dict, respectively.

List of properties

For the Fluid and Mixture instances:

• compressibility - compressibility factor (-)
• conductivity - thermal conductivity (W/m/K)
• critical_pressure - absolute pressure at the critical point (Pa)
• critical_temperature - absolute temperature at the critical point (K)
• density - mass density (kg/m3)
• dynamic_viscosity - dynamic viscosity (Pa*s)
• enthalpy - mass specific enthalpy (J/kg)
• entropy - mass specific entropy (J/kg/K)
• freezing_temperature - temperature at freezing point (for incompressible fluids) (K)
• internal_energy - mass specific internal energy (J/kg)
• max_pressure - maximum pressure limit (Pa)
• max_temperature - maximum temperature limit (K)
• min_pressure - minimum pressure limit (Pa)
• min_temperature - minimum temperature limit (K)
• molar_mass - molar mass (kg/mol)
• phase - phase
• prandtl - Prandtl number (-)
• pressure - absolute pressure (Pa)
• quality - mass vapor quality (-)
• sound_speed - sound speed (m/s)
• specific_heat - mass specific constant pressure specific heat (J/kg/K)
• surface_tension - surface tension (N/m)
• temperature - absolute temperature (K)
• triple_pressure - absolute pressure at the triple point (Pa)
• triple_temperature - absolute temperature at the triple point (K)

For the HumidAir instances:

• compressibility - compressibility factor (-)
• conductivity - thermal conductivity (W/m/K)
• density - mass density per humid air unit (kg/m3)
• dew_temperature - dew-point absolute temperature (K)
• dynamic_viscosity - dynamic viscosity (Pa*s)
• enthalpy - mass specific enthalpy per humid air (J/kg)
• entropy - mass specific entropy per humid air (J/kg/K)
• humidity - absolute humidity ratio (kg/kg d.a.)
• partial_pressure - partial pressure of water vapor (Pa)
• pressure - absolute pressure (Pa)
• relative_humidity - relative humidity ratio (from 0 to 1) (-)
• specific_heat - mass specific constant pressure specific heat per humid air (J/kg/K)
• temperature - absolute dry-bulb temperature (K)
• wb_temperature - absolute wet-bulb temperature (K)

NB. If the required property is not present in the instance of the fluid, then you can add it using the add_props method.

Examples

To calculate the specific heat of saturated water vapour at 101325 Pa:

from pyfluids import Fluid, PureFluids, Input

water_vapour = Fluid(PureFluids.Water)
water_vapour.update(Input.Pressure.with_value(101325), Input.Quality.with_value(1))
print(water_vapour.specific_heat)  # 2079.937085633241

To calculate the dynamic viscosity of propylene glycol aqueous solution with 60 % mass fraction at 101325 Pa and 253.15 K:

from pyfluids import Fluid, IncompMixturesMF, Input

propylene_glycol = Fluid(IncompMixturesMF.MPG, 0.6)
propylene_glycol.update(
    Input.Pressure.with_value(101325), Input.Temperature.with_value(253.15)
)
print(propylene_glycol.dynamic_viscosity)  # 0.13907391053938847

To calculate the density of ethanol aqueous solution (with ethanol 40 % mass fraction) at 200 kPa and 277.15 K:

from pyfluids import Mixture, PureFluids, Input

mixture = Mixture([PureFluids.Water, PureFluids.Ethanol], [0.6, 0.4])
mixture.update(Input.Pressure.with_value(200e3), Input.Temperature.with_value(277.15))
print(mixture.density)  # 883.3922771627759

To calculate the wet bulb temperature of humid air at 99 kPa, 303.15 K and 50 % relative humidity:

from pyfluids import HumidAir, HAInput

humid_air = HumidAir()
humid_air.update(
    HAInput.Pressure.with_value(99e3),
    HAInput.Temperature.with_value(303.15),
    HAInput.RelativeHumidity.with_value(0.5),
)
print(humid_air.wb_temperature)  # 295.0965785590792