NeqSim Base Modules

This document provides an overview of the seven foundational modules that make up NeqSim. Each module resides under src/main/java/neqsim and works together to support fluid characterization and process design.

Thermodynamic routines

• Location: thermo and thermodynamicoperations
• Features: fluid phase equilibria, equation-of-state implementations, flash and phase envelope calculations.

Physical properties routines

• Location: physicalproperties
• Features: density, viscosity, heat capacity and other transport properties calculated from thermodynamic state.

Fluid mechanic routines

• Location: fluidmechanics
• Features: models for steady-state and transient flow, pipeline hydraulics, and flow node/leg modelling.

Unit operations

• Location: process/equipment
• Features: library of process equipment including separators, heat exchangers, valves and other common unit operations.

Chemical reactions routines

• Location: chemicalreactions
• Features: equilibrium and kinetic reaction models with support for reaction mechanisms and kinetic rate expressions.

Parameter fitting routines

• Location: statistics/parameterfitting
• Features: tools for regression and parameter estimation using experimental data, including Monte Carlo simulations.

Process simulation routines

• Location: process
• Features: framework for assembling flowsheets and running dynamic or steady-state process simulations that couple unit operations and property packages.

Process safety simulation

• Location: process/safety, process/equipment/tank, process/util/fire
• Features: comprehensive safety simulation capabilities including:
  • Depressurization: Dynamic vessel blowdown with multiple thermodynamic modes (isothermal, isentropic, energy balance), fire case modeling, and transient wall heat transfer
  • Relief valve sizing: API 520/521 compliant PSV sizing with dynamic fire scenarios
  • Source term generation: Leak/rupture mass flow, jet velocity, and momentum calculations for consequence modeling (PHAST, FLACS, KFX export)
  • Safety envelopes: Hydrate, WAX, CO2 freezing, and MDMT envelope calculations with operating point validation
  • Risk framework: Monte Carlo and deterministic risk analysis with event trees, sensitivity analysis, and F-N curve generation