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NeqSim Documentation

NeqSim (Non-Equilibrium Simulator) is a comprehensive Java library for thermodynamic, physical property, and process simulation developed by Equinor.

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๐Ÿš€ Get Started โญ Star on GitHub ๐Ÿ“– Reference Manual

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โšก Quick Start Example

import neqsim.thermo.system.SystemSrkEos;
import neqsim.thermodynamicoperations.ThermodynamicOperations;

// Create a natural gas fluid
SystemInterface gas = new SystemSrkEos(298.15, 50.0);
gas.addComponent("methane", 0.90);
gas.addComponent("ethane", 0.05);
gas.addComponent("propane", 0.03);
gas.addComponent("CO2", 0.02);
gas.setMixingRule("classic");

// Perform flash calculation
ThermodynamicOperations ops = new ThermodynamicOperations(gas);
ops.TPflash();

// Get properties
System.out.println("Density: " + gas.getDensity("kg/m3") + " kg/mยณ");
System.out.println("Compressibility: " + gas.getZ());

๐Ÿ“– Documentation Sections

Section Description
๐Ÿงช ThermodynamicsEquations of state, phase behavior, component properties
โš™๏ธ Process SimulationUnit operations, process systems, controllers
๐Ÿ“Š Physical PropertiesTransport properties, interfacial tension
๐Ÿ›ข๏ธ PVT SimulationReservoir fluid characterization, tuning
๐ŸŒŠ Fluid MechanicsPipeline flow, multiphase modeling
๐Ÿ’ก ExamplesTutorials and code samples
๐Ÿ”ง DevelopmentContributing guidelines, developer setup

๐Ÿ“š Interactive Reference Manual

The Interactive Reference Manual provides a searchable, navigable guide to all NeqSim packages:

โœ… Complete package hierarchy
โœ… Class and interface listings
โœ… Usage examples and snippets
โœ… Cross-referenced links

๐Ÿ Python Integration

NeqSim is also available for Python through neqsim-python:

from neqsim.thermo import TPflash, fluid

# Create and flash a natural gas
gas = fluid("srk")
gas.addComponent("methane", 0.9)
gas.addComponent("ethane", 0.1)
gas.setTemperature(298.15, "K")
gas.setPressure(50.0, "bara")

TPflash(gas)
print(f"Gas density: {gas.getDensity('kg/m3'):.2f} kg/mยณ")

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