Welcome to barotropy’s documentation!#
Enhance your two-phase turbomachinery CFD simulations with barotropy, a Python package designed to generate barotropic fluid property models for use in CFD simlations.
A barotropic model assumes that thermophysical properties such as density, viscosity, and speed of sound depend only on pressure. This simplification is highly accurate for flows in which the fluid approximately follows a known thermodynamic process, such as a polytropic processes in turbines and compressors. This simplification enables:
Efficient and stable CFD convergence
Physically plausible extrapolation near critical or two-phase conditions
Seamless integration with pressure-based CFD solvers such as Fluent or CFX
Using a barotropic model in the context of a CFD simulation does not imply that the flow is frictionless. This is because momentum equations still have dissipation terms due to viscous friction. Instead, the implication of using the barotropic model is that the variation of fluid properties caused by viscous dissipation described by the polytropic process.
The thermodynamic properties are computed using the CoolProp library. Once computed, the fluid properties are automatically fitted with piece-wise polynomials and exported as Expressions to be used in conjunction with Fluent’s or CFX’s pressure-based solvers.
Two-phase fluid properties between the saturation line and the spinodal line can be computed according to phase-equilibrium or by extrapolating the Helmholtz-energy equation of state into the metastable region. Check the documentation for more information about extrapolating the equation of state beyond the saturation line and its limitations.
Table of contents#
Use the panel to the left or the table of contents below to navigate the documentation.