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Welcome to ℜeos

ℜeos is a thermodynamic library written in Rust with a Python interface. It provides tools for calculating thermodynamic properties and phase equilibria.

import numpy as np
from reos.cpa import CPAParameters, CPAPureRecord
from reos.eos import EquationOfState
from reos.state import State

parameters = CPAParameters.from_records([ 
    CPAPureRecord.new(
        name = "water",
        molar_weight = 18.01528,
        a0 = 0.12277,
        b = 0.014515e-3,
        c1 = 0.67359,
        tc = 647.29,
        epsilon = 166.55e2,
        kappa = 0.0692,
        na = 2,
        nb = 2
    )
])

# or  CPAParameters.from_json(["water"], "./parameters/cpa/kontogeorgis2006.json")

eos = EquationOfState.scpa(parameters)

t = 298.15
p = 1e5
x = np.array([1.0])

s = State.tpx(eos, t, p, x) 

print(s)

X = eos.unbonded_sites_fraction(t, s.density, x)

print(f"Unbonded sites fraction = {X}")

State(t = 298.150 K, p = 100000.000000 Pa, ρ = 55784.919890 mol/m³)
Unbonded sites fraction = [0.07825138 0.07825138]

Models

Model Description
CPA Cubic Plus Association (srk, pr76, pr78)
cubic Soave-Redlich-Kwong, Peng-Robinson 1976, Peng-Robinson 1978

Each model implement its analytical expressions of derived properties of Helmholtz potential.

Installation

Python

From pip

pip install reos

From source

You must have rust compiler and maturin/PyO3 installed.

To install the python package in your machine (such pip install -e .) and use the optimized version of the package:

cd pyreos
maturin develop --release

To build the the python wheel, just use

maturin build --release

Project layout

Repository

├── crates
├── parameters
├── pyreos
├── pyreos-dev
└── pyreos-examples

  • parameters: Directory with pure and binary parameters for the current models implemented in Reos

  • crates: Contains reos, which is the Rust package that implement all the core functionalites

  • pyreos: Rust package that create the Python interface from reos

  • pyreos-dev: Directory used to test functionalites of reos in Python

  • pyreos-examples: Python examples of how to use reos

Python package

  • reos.eos: Enables the creation and manipulation of equations of state with different models.
  • reos.state: Provides tools for working with thermodynamic states, including property calculations and phase equilibria.
  • reos.{model_name}: Each current model has its own submodule with its name, which contains the pure model record, the binary model record and the parameters objects .