Compositional Model

This project implements a compositional reservoir model in Python to simulate the phase behavior of multicomponent hydrocarbon systems. The model explicitly tracks fluid composition and phase equilibrium, providing a more detailed and rigorous description of reservoir fluids than black-oil formulations. It is intended for educational purposes and as a foundation for future compositional reservoir simulation development.

Requirements

• Python 3.10+ (It is not recommended to use the latest version)
• Dependencies listed in requirements.txt (numpy, math, barril)

Installation and Usage

Clone the repository and create a virtual environment:

python -m venv venv
venv\Scripts\activate
pip install -r requirements.txt

Then run the main script:

python main.py

Project Structure

• main.py – main execution script
• requirements.txt – project dependencies
• venv/ – virtual environment

Thermodynamic Model

Based on classical thermodynamic principles, the model solves the phase-equilibrium problem through a compositional flash calculation. The flash formulation determines phase compositions and phase fractions by enforcing equality of component fugacities between phases, using a cubic equation of state with the Soave–Redlich–Kwong correlation. Phase stability and equilibrium are assessed through Gibbs free energy criteria inherent to the fugacity-based formulation. For the implicits nonlinear equations we solved using the Newton–Raphson method. Once equilibrium compositions and phase fractions are obtained, volumetric and thermophysical properties are calculated from the equation-of-state results.