| name | neqsim-capability-map |
| description | Structured inventory of NeqSim's capabilities by engineering discipline. USE WHEN: checking what NeqSim can do, planning implementations, assessing gaps for engineering tasks, or routing work to the right agent. Covers thermodynamics, process equipment, PVT, standards, mechanical design, flow assurance, safety, and economics. |
| last_verified | 2026-08-02 |
NeqSim Capability Map
Structured reference of what NeqSim can do, organized by engineering discipline.
Use this to quickly check if a capability exists before searching the source code.
Last updated: 2026-08-02
A. Thermodynamic Models (Equations of State)
Cubic EOS
| Class | Fluid Type | Mixing Rule | Notes |
|---|
SystemSrkEos | Dry/lean gas, simple HC | "classic" | Most common choice |
SystemPrEos | General HC, oil systems | "classic" | Better liquid densities than SRK |
SystemPrEos1978 | HC with Peng-Robinson 1978 | "classic" | Updated alpha function |
SystemPrEosvolcor | PR with volume correction | "classic" | Volume-translated PR |
SystemSrkEosvolcor | SRK with volume correction | "classic" | Volume-translated SRK |
SystemSrkPenelouxEos | SRK with Peneloux correction | "classic" | Volume shift |
SystemSrkMathiasCopeman | SRK + Mathias-Copeman alpha | "classic" | Better vapor pressure fit |
SystemPrMathiasCopeman | PR + Mathias-Copeman alpha | "classic" | Better vapor pressure fit |
SystemSrkTwuCoonEos | SRK + Twu-Coon alpha | "classic" | TST-type alpha function |
SystemRKEos | Redlich-Kwong (original) | "classic" | Historical / teaching |
SystemPrDanesh | PR-Danesh variant | "classic" | Oil recovery applications |
SystemPsrkEos | Predictive SRK (group contribution) | — | No BIPs needed for some systems |
SystemSrkSchwartzentruberEos | SRK + Schwarzentruber-Renon | "classic" | Polar compounds |
Association & Polar EOS (CPA)
| Class | Fluid Type | Mixing Rule | Notes |
|---|
SystemSrkCPAstatoil | Water, MEG, methanol, polar | 10 (numeric) | Primary CPA choice |
SystemSrkCPA | CPA (generic) | 10 | Base CPA |
SystemSrkCPAs | CPA simplified | 10 | Faster CPA variant |
SystemPrCPA | PR-based CPA | 10 | PR + association |
SystemElectrolyteCPAstatoil | Brines, salt solutions | 10 | Electrolyte + CPA |
SystemElectrolyteCPA | Electrolyte CPA | 10 | Base electrolyte |
Reference EOS (High Accuracy)
| Class | Fluid Type | Notes |
|---|
SystemGERG2008Eos | Natural gas (custody transfer) | ISO 20765, highest accuracy |
SystemGERG2004Eos | Natural gas (older GERG) | Predecessor to 2008 |
SystemSpanWagnerEos | Pure CO2 | CO2 reference EOS |
SystemLeachmanEos | Pure hydrogen | H2 reference EOS |
SystemWaterIF97 | Pure water / steam | IAPWS-IF97 |
SystemVegaEos | LNG / cryogenic | Specialized for LNG |
SAFT Family
| Class | Fluid Type | Notes |
|---|
SystemPCSAFT | Polymers, associating | PC-SAFT |
SystemPCSAFTa | PC-SAFT variant | Alternative parameterization |
Other / Specialized
| Class | Fluid Type | Notes |
|---|
SystemBWRSEos | Benedict-Webb-Rubin-Starling | Only CH4 + C2H6 parameterized |
SystemIdealGas | Ideal gas law | Teaching / reference |
SystemBnsEos | BNS EOS | Specialized |
SystemUMRPRUEos | UMRPRU group contribution | Predictive mixing rules |
SystemNRTL | Activity coefficient (NRTL) | Liquid-liquid equilibrium |
SystemUNIFAC | Activity coefficient (UNIFAC) | Group contribution |
SystemSoreideWhitson | Soreide-Whitson for oil/water | HC-water mutual solubility |
SystemKentEisenberg | Acid gas treating | H2S/CO2 in amines |
SystemDesmukhMather | Acid gas treating | Amine systems |
SystemDuanSun | CO2 in brine | CO2 solubility |
SystemAmmoniaEos | Ammonia systems | NH3-specific |
Package: neqsim.thermo.system
B. Flash Calculations (ThermodynamicOperations)
| Method | Class/Operation | Notes |
|---|
| TP flash | ops.TPflash() | Standard pressure-temperature |
| PH flash | ops.PHflash() | Pressure-enthalpy |
| PS flash | ops.PSflash() | Pressure-entropy |
| TV flash | ops.TVflash() | Temperature-volume |
| UV flash | ops.UVflash() | Internal energy-volume |
| Dew point P | ops.dewPointPressureFlash() | At given T |
| Dew point T | ops.dewPointTemperatureFlash() | At given P |
| Bubble point P | ops.bubblePointPressureFlash() | At given T |
| Bubble point T | ops.bubblePointTemperatureFlash() | At given P |
| Phase envelope | ops.calcPTphaseEnvelope() | Full PT envelope |
| Cricondenbar | ops.calcPTphaseEnvelope() → .get("cricondenbar") | Max pressure on envelope |
| Cricondentherm | ops.calcPTphaseEnvelope() → .get("cricondentherm") | Max temperature on envelope |
| Solid flash | ops.TPSolidflash() | Wax, hydrate, ice, S8 precipitation |
| Hydrate T | ops.hydrateEquilibriumTemperature() | Hydrate formation temperature |
| Hydrate P | ops.hydrateFormationPressure() | Hydrate formation pressure |
| Wax T | ops.calcWAT() | Wax appearance temperature |
| Freeze T | ops.freezingPointTemperatureFlash() | Freeze-out temperature |
| Water dew point | ops.waterDewPointTemperature() | Water content specification |
CRITICAL: After any flash, call fluid.initProperties() before reading
transport properties (viscosity, thermal conductivity, density).
Package: neqsim.thermodynamicoperations
C. Process Equipment
Separation
| Class | Type | Package |
|---|
Separator | 2-phase (gas/liquid) | process.equipment.separator |
ThreePhaseSeparator | 3-phase (gas/oil/water) | process.equipment.separator |
GasScrubber | Gas scrubbing | process.equipment.separator |
GasScrubberSimple | Simplified scrubber | process.equipment.separator |
NeqSeparator | Non-equilibrium separator | process.equipment.separator |
Compression & Expansion
| Class | Type | Package |
|---|
Compressor | Centrifugal / reciprocating | process.equipment.compressor |
CompressorChart | Performance curves | process.equipment.compressor |
Expander | Turbo-expander | process.equipment.expander |
Heat Transfer
| Class | Type | Package |
|---|
Heater | Generic heater (duty specification) | process.equipment.heatexchanger |
Cooler | Generic cooler (duty specification) | process.equipment.heatexchanger |
HeatExchanger | Shell-and-tube (2 streams) | process.equipment.heatexchanger |
NeqHeater | Non-equilibrium heater | process.equipment.heatexchanger |
Valves & Pressure Control
| Class | Type | Package |
|---|
ThrottlingValve | Isenthalpic flash | process.equipment.valve |
Distillation & Absorption
| Class | Type | Package |
|---|
DistillationColumn | Tray column | process.equipment.distillation |
Condenser | Column condenser | process.equipment.distillation |
Reboiler | Column reboiler | process.equipment.distillation |
SimpleTEGAbsorber | TEG absorption | process.equipment.absorber |
SimpleAbsorber | Generic absorber | process.equipment.absorber |
WaterStripperColumn | Water stripper | process.equipment.absorber |
Mixing & Splitting
| Class | Type | Package |
|---|
Mixer | Stream mixing | process.equipment.mixer |
StaticMixer | In-line mixer | process.equipment.mixer |
Splitter | Stream splitting | process.equipment.splitter |
ComponentSplitter | Component-based split | process.equipment.splitter |
Pipelines & CO2 Well Analysis
| Class | Type | Package |
|---|
AdiabaticPipe | Adiabatic pipe flow | process.equipment.pipeline |
PipeBeggsAndBrills | Beggs & Brill correlation (+ formation temperature gradient) | process.equipment.pipeline |
PipeGray | Gray (1974) multiphase vertical flow for gas / gas-condensate wells (Woldesemayat-Ghajar holdup option) | process.equipment.pipeline |
VoidFractionCorrelations | Two-phase void-fraction / gas-holdup correlations (Woldesemayat-Ghajar 2007) | process.equipment.pipeline |
TwoFluidPipe | Transient two-fluid multiphase model with 7 conservation equations, AUSM+, boundary conditions, direct electrical heating (DEH). See neqsim-flow-assurance for validity limits | process.equipment.pipeline |
CO2InjectionWellAnalyzer | CO2 injection well safety analysis | process.equipment.pipeline |
TransientWellbore | Shutdown cooling / depressurization transient | process.equipment.pipeline |
CO2FlowCorrections | CO2-specific two-phase flow corrections (static utility) | process.equipment.pipeline |
InterfacialFriction | Interfacial friction closures (Taitel-Dukler, Andritsos-Hanratty, Wallis, Oliemans) | process.equipment.pipeline.twophasepipe.closure |
OnePhasePipeFlowNode | Single-phase pipe | fluidmechanics |
TwoPhasePipeFlowNode | Two-phase pipe | fluidmechanics |
Reactors
| Class | Type | Package |
|---|
GibbsReactor | Gibbs energy minimization | process.equipment.reactor |
GibbsReactorCO2 | CO2-focused Gibbs reactor | process.equipment.reactor |
StoichiometricReaction | Stoichiometric reactions | process.equipment.reactor |
StirredTankReactor | CSTR | process.equipment.reactor |
FurnaceBurner | Combustion | process.equipment.reactor |
SulfurDepositionAnalyser | S8 deposition analysis | process.equipment.reactor |
AmmoniaSynthesisReactor | NH3 synthesis | process.equipment.reactor |
AnaerobicDigester | Biogas production (AD) | process.equipment.reactor |
FermentationReactor | Monod/Contois/substrate-inhibited kinetics | process.equipment.reactor |
BiogasUpgrader | Biogas upgrading (membrane, PSA, amine, water scrub) | process.equipment.splitter |
BiomassGasifier | Thermochemical gasification | process.equipment.reactor |
PyrolysisReactor | Fast/slow/flash pyrolysis | process.equipment.reactor |
Biorefinery Modules (Pre-built)
| Class | Type | Package |
|---|
BiogasToGridModule | AD → upgrading → compression → grid | process.processmodel.biorefinery |
GasificationSynthesisModule | Biomass gasification + Fischer-Tropsch | process.processmodel.biorefinery |
WasteToEnergyCHPModule | AD → gas engine CHP | process.processmodel.biorefinery |
Sustainability & Cost
| Class | Type | Package |
|---|
SustainabilityMetrics | CO₂eq tracking, carbon intensity, EROI | process.util.fielddevelopment |
BiomassCharacterization | Biomass properties (proximate, ultimate, HHV) | thermo.characterization |
BiorefineryCostEstimator | CAPEX/OPEX for biorefinery equipment | process.mechanicaldesign |
Measurement Devices & Instrumentation
| Class | Type | Package |
|---|
ImpurityMonitor | Phase-partitioned impurity tracker with alarms | process.measurementdevice |
PressureTransmitter | Pressure measurement (PT) | process.measurementdevice |
TemperatureTransmitter | Temperature measurement (TT) | process.measurementdevice |
LevelTransmitter | Level measurement (LT) | process.measurementdevice |
VolumeFlowTransmitter | Volume flow measurement (FT) | process.measurementdevice |
MassFlowTransmitter | Mass flow measurement | process.measurementdevice |
WaterDewPointAnalyser | Water dew point measurement | process.measurementdevice |
HydrocarbonDewPointAnalyser | HC dew point measurement | process.measurementdevice |
WaterContentAnalyser | Water content measurement | process.measurementdevice |
CO2waterAnalyser | CO2 in water measurement | process.measurementdevice |
AlarmConfig | Alarm HH/H/L/LL thresholds per IEC 61511 | process.measurementdevice |
AlarmState | Current alarm state tracking | process.measurementdevice |
ProcessAlarmManager | System-wide alarm management | process.measurementdevice |
InstrumentTagRole | Tag role classification (INPUT/BENCHMARK/VIRTUAL) | process.measurementdevice |
ControllerDeviceBaseClass |
Pumps
| Class | Type | Package |
|---|
Pump | Liquid pump | process.equipment.pump |
Subsea & Wells
| Class | Type | Package |
|---|
SubseaWell | Subsea well model | process.equipment.subsea |
Utilities & Special
| Class | Type | Package |
|---|
Recycle | Stream recycle convergence | process.equipment.util |
Adjuster | Variable adjuster | process.equipment.util |
SetPoint | Set point controller | process.equipment.util |
Calculator | Custom calculator | process.equipment.util |
StreamSaturatorUtil | Stream saturation | process.equipment.util |
GasGenerator | Gas generation | process.equipment.util |
Flare | Flare system | process.equipment.flare |
Filter | Particle filter | process.equipment.filter |
Ejector | Ejector / eductor | process.equipment.ejector |
Electrolyzer | Water electrolysis | process.equipment.electrolyzer |
Tank | Storage tank | process.equipment.tank |
Manifold | Production / gathering / commingling / export / subsea manifold & headers — use for ALL manifolds, not Mixer/Splitter. Always route downstream from a split stream: single destination → setSplitFactors([1.0]) + getSplitStream(0); multiple → setSplitFactors([...]) + getSplitStream(i). getMixedStream() = internal commingled stream (before split), inspection only | process.equipment.manifold |
SimpleReservoir | Simple reservoir model | process.equipment.reservoir |
Process System
| Class | Type | Package |
|---|
ProcessSystem | Flowsheet container | process.processmodel |
ProcessConnection | Equipment connections | process.processmodel |
D. PVT Simulations
| Class | Experiment | Package |
|---|
ConstantMassExpansion | CME / CCE | pvtsimulation.simulation |
ConstantVolumeDepletion | CVD | pvtsimulation.simulation |
DifferentialLiberation | Differential liberation | pvtsimulation.simulation |
SeparatorTest | Multi-stage separator test | pvtsimulation.simulation |
SwellingTest | Gas injection swelling | pvtsimulation.simulation |
SaturationPressure | Bubble/dew point P | pvtsimulation.simulation |
SaturationTemperature | Bubble/dew point T | pvtsimulation.simulation |
SlimTube | Slim tube / MMP | pvtsimulation.simulation |
ViscositySimulation | Viscosity vs P | pvtsimulation.simulation |
GOR | Gas-oil ratio vs P | pvtsimulation.simulation |
Reservoir Material Balance & Surveillance (inverse)
| Class | Assessment | Package |
|---|
DeclineCurveAnalysis | Arps + Duong (2011) decline; forward rate/EUR and least-squares history matching (fitArps, fitDuong) | pvtsimulation.util |
GasMaterialBalance | Gas P/Z straight line (OGIP), Cole plot aquifer diagnostic, Havlena-Odeh | pvtsimulation.reservoirproperties.materialbalance |
OilMaterialBalance | Havlena-Odeh oil balance (OOIP, gas-cap ratio m, water drive, Pirson drive indices) | pvtsimulation.reservoirproperties.materialbalance |
VanEverdingenHurstAquifer | Radial aquifer influence functions, Carter-Tracy cumulative influx, ECLIPSE AQUTAB export | pvtsimulation.reservoirproperties.materialbalance |
Flow Assurance (PVT module)
| Class | Assessment | Package |
|---|
DeWaardMilliamsCorrosion | CO2/H2S corrosion rate (screening) | pvtsimulation.flowassurance |
Corrosion & Scale (process module)
| Class | Assessment | Package |
|---|
NorsokM506CorrosionRate | NORSOK M-506 CO2 corrosion (fugacity, in-situ pH, FeCO3 film, shear, glycol/inhibitor) | process.corrosion |
NorsokM506ElectrolyteBridge | Drives NORSOK M-506 from a SystemElectrolyteCPAstatoil brine (rigorous pH + FeCO3 supersaturation) | process.corrosion |
CO2CorrosionAnalyzer | de Waard-Milliams from an electrolyte fluid | pvtsimulation.flowassurance |
PipeSegmentIntegrity | Per-segment CO2 corrosion + CaCO3 scale profile along a line (fromPipe) | process.corrosion |
RobustAqueousPH | Always-finite, source-tagged in-situ pH with explicit pCO2 basis (rigorous else CO2-water correlation) | process.corrosion |
FlowAcceleratedCorrosion | FAC screening index for closed hot-water/glycol loops: Berger-Hau mass transfer, 150 °C solubility peak, pH, bend/weld geometry, Cr content. Distinct from erosion-corrosion and from NORSOK M-506 CO2 corrosion | process.corrosion |
AmineBufferedPH | Converts a laboratory pH measured on a cooled sample into in-situ pH at operating temperature, and reports the alkaline margin above neutrality (neutral is pH 5.85 at 150 °C, not 7) | process.corrosion |
Phase.getpH() | Aqueous in-situ pH; built-in acid-gas fallback (getpH("acidgas")) gives CO2/H2S pH without chemicalReactionInit() | thermo.phase |
ElectrolyteScaleCalculator | Activity-corrected SI for CaCO3/BaSO4/CaSO4/SrSO4 (Davies + Ksp(T)) from ion mg/L | process.chemistry.scale |
ThermodynamicOperations.checkScalePotential(phase) | Rigorous saturation ratio SR=IAP/Ksp per salt from a speciated brine (needs chemicalReactionInit()); read getResultTable() |
Regression / Tuning
| Class | Purpose | Package |
|---|
ModelTuning | EOS parameter fitting | pvtsimulation.modeltuning |
E. Gas Quality Standards
| Class | Standard | Package |
|---|
Standard_ISO6976 | ISO 6976 — calorific value, Wobbe, density | standards.gasquality |
Standard_ISO6976_2016 | ISO 6976:2016 update | standards.gasquality |
Standard_ISO6578 | ISO 6578 — LNG custody transfer | standards.gasquality |
Standard_ISO15403 | ISO 15403 — natural gas for vehicles | standards.gasquality |
Standard_EN16726 | EN 16726 — European gas quality | standards.gasquality |
UKgasQuality | UK gas quality specification | standards.gasquality |
GasChromatographData | GC data processing | standards.gasquality |
BrackettedMolarComposition | Molar composition bracketing | standards.gasquality |
Draft_GERG2004 | GERG-2004 draft implementation | standards.gasquality |
SulfurSpecificationMethod | H2S / total sulfur limits | standards.gasquality |
Oil Quality
| Class | Standard | Package |
|---|
Standard_ASTM_D6377 | ASTM D6377 — vapor pressure | standards.oilquality |
Standard_ASTM_D2887 | ASTM D2887 — simulated distillation | standards.oilquality |
Standard_ASTM_D4294 | ASTM D4294 — sulfur in oil | standards.oilquality |
F. Mechanical Design
| Class | Equipment | Package |
|---|
MechanicalDesign | Base class | process.mechanicaldesign |
SeparatorMechanicalDesign | Separator vessel sizing, K-factor, demister config, nozzle sizing, liquid levels (HHLL/HLL/NLL/LLL/LLLL), inlet device, foam allowance, retention time, entrainment performance, design validation. Gateway for all separator physical configuration. Bridge methods: entrainment (setInletPipeDiameter, setInletDeviceType, addSeparatorSection, setGasLiquidSurfaceTension) and dynamic internals (setWeirHeightAbsolute, setWeirLength, setBootVolume, setMistEliminatorDpCoeff, setMistEliminatorThickness, applyDemistingInternal). Separation-efficiency report (calculateSeparationEfficiency() → SeparatorEfficiencyReport, two- and three-phase; setEfficiencyModelEnabled(bool) toggle; setDemisterType/setDemisterSubType). | process.mechanicaldesign.separator |
SeparatorEfficiencyReport | Whole-separator/scrubber separation-efficiency report — per-internal K-factor operating windows, overall gas-liquid efficiency, gas/oil/water entrainment + carry-under fractions, verdict (GOOD_PERFORMANCE/BELOW_TURNDOWN/FLOODING_RISK/MARGINAL_EFFICIENCY), toJson(). | process.mechanicaldesign.separator |
InternalOperatingWindow | K-factor operating window for a demisting internal — classifies operating Souders-Brown K vs [Kmin, Kmax] as BELOW_MIN_TURNDOWN/IN_RANGE/ABOVE_MAX_FLOODING, with utilization and turndown ratio. | process.mechanicaldesign.separator.internals |
DemistingInternal | Demisting internal sizing — Souders-Brown max gas velocity, Eu-number pressure drop, carry-over model, database K-factor window (, ). Types: wire mesh, vane pack, cyclone. |
Engineering Deliverables
| Class | Purpose | Package |
|---|
StudyClass | Enum (CLASS_A/CLASS_B/CLASS_C) defining required deliverables per study tier | process.mechanicaldesign |
EngineeringDeliverablesPackage | Orchestrates generation of all deliverables for a study class | process.mechanicaldesign |
ProcessFlowDiagramExporter | Graphviz DOT export of ProcessSystem topology | process.processmodel |
ThermalUtilitySummary | Cooling water, LP/MP/HP steam, fuel gas, instrument air | process.mechanicaldesign |
AlarmTripScheduleGenerator | Alarm/trip setpoints per IEC 61511 / NORSOK I-001 | process.mechanicaldesign |
InstrumentScheduleGenerator | ISA-5.1 tagged instrument schedule with live MeasurementDevice bridge | process.mechanicaldesign |
SparePartsInventory | Recommended spare parts by equipment type with lead times | process.mechanicaldesign |
FireProtectionDesign | Jet fire, BLEVE, pool fire scenario assessment (API 521) | process.mechanicaldesign.designstandards |
NoiseAssessment | Equipment noise + ISO 9613-2 atmospheric attenuation | process.mechanicaldesign.designstandards |
Electrical Design
| Class | Purpose | Package |
|---|
ElectricalDesign | Base class — sizes motor, VFD, cables, switchgear | process.electricaldesign |
ElectricalMotor | AC induction motor model (IEC 60034, IEEE 841) | process.electricaldesign.components |
VariableFrequencyDrive | VFD with topology, harmonics, efficiency | process.electricaldesign.components |
ElectricalCable | Cable sizing with derating (IEC 60502) | process.electricaldesign.components |
Transformer | Power transformer model (IEC 60076) | process.electricaldesign.components |
Switchgear | MCC / switchgear bucket (IEC 61439) | process.electricaldesign.components |
HazardousAreaClassification | Zone / Ex marking (IEC 60079) | process.electricaldesign.components |
CompressorElectricalDesign | Compressor-specific with auxiliary loads | process.electricaldesign.compressor |
PumpElectricalDesign | Pump-specific design | process.electricaldesign.pump |
SeparatorElectricalDesign | Separator auxiliary loads | process.electricaldesign.separator |
HeatExchangerElectricalDesign | Electric heater / air cooler / S&T detection | process.electricaldesign.heatexchanger |
PipelineElectricalDesign | Heat tracing, cathodic protection | process.electricaldesign.pipeline |
SystemElectricalDesign | Plant-wide load aggregation, transformer sizing | process.electricaldesign.system |
ElectricalLoadList |
G. Physical Properties
| Class | Property | Package |
|---|
PhysicalPropertyHandler | Property dispatcher | physicalproperties |
| Viscosity models | Gas/liquid/mixing rule | physicalproperties.methods |
| Thermal conductivity | Gas/liquid | physicalproperties.methods |
| Diffusion coefficients | Binary diffusion | physicalproperties.methods |
Access pattern: After fluid.initProperties(), use:
fluid.getPhase("gas").getViscosity("kg/msec")fluid.getPhase("gas").getThermalConductivity("W/mK")fluid.getPhase("gas").getDensity("kg/m3")
H. Utility Classes
| Class | Purpose | Package |
|---|
FluidBuilder | Fluent fluid construction | thermo.system |
HeatMaterialBalance | Process-wide H&M balance | util.engineering |
SensitivityAnalysis | Parametric sweeps | util.engineering |
MonteCarloSimulator | Monte Carlo sampling | util.engineering |
ConvergenceDiagnostics | Solver diagnostics | util.engineering |
HydrateRiskMapper | Hydrate risk matrix | util.engineering |
EOSComparison | Multi-EOS comparison | util.engineering |
PinchAnalyzer | Pinch analysis (heat integration) | util.engineering |
DCFCalculator | NPV / DCF economics | util.engineering |
DebottleneckAnalyzer | Capacity bottleneck finding | util.engineering |
ProcessValidator | Equipment validation | util.engineering |
CoolingWaterSystem | Cooling water sizing | process.equipment.heatexchanger |
FiredHeater | Fired heater modeling | process.equipment.heatexchanger |
I. Chemical Reactions
| Capability | Implementation | Notes |
|---|
| Gibbs energy minimization | GibbsReactor | Newton-Raphson, element balanced |
| Stoichiometric reactions | StoichiometricReaction | User-defined reactions |
| Combustion | FurnaceBurner | Fuel gas combustion |
| Sulfur reactions | SulfurDepositionAnalyser | Claus + corrosion reactions |
| Ammonia synthesis | AmmoniaSynthesisReactor | Haber-Bosch |
| Chemical equilibrium DB | GibbsReactDatabase.csv | Thermodynamic data |
| Runaway reaction screening | RunawayReactionAnalyzer | Lumped adiabatic: MTSR, dT_ad, TMR_ad. No spatial conduction |
| Self-heating criticality | PorousMediaSelfHeatingAnalyzer | Frank-Kamenetskii; critical thickness & temperature for lagging fires |
| Self-heating (surface-cooled) | SemenovSelfHeatingAnalyzer | Semenov 1/e criterion for pools and thin films |
| Time to spontaneous ignition | SelfHeatingInductionSolver | Transient 1-D conduction + Arrhenius source |
| Oxidation kinetics from oven tests | BasketTestRegression | Fits E and P from EN 15188 / ASTM E2021 basket data |
I-bis. Bioprocessing & Bioenergy
| Capability | Implementation | Notes |
|---|
| Anaerobic digestion | AnaerobicDigester | Substrate-specific biogas yields (food waste, sewage, manure, crop residue) |
| Fermentation kinetics | FermentationReactor | Monod, Contois, substrate-inhibited; batch, fed-batch, continuous |
| Biogas upgrading | BiogasUpgrader | Water scrubbing, amine, PSA, membrane; auto CH4/CO2 split |
| Biomass gasification | BiomassGasifier | Air/oxygen/steam; syngas composition from biomass properties |
| Pyrolysis | PyrolysisReactor | Fast, slow, flash; bio-oil, char, gas yields |
| Sustainability / LCA | SustainabilityMetrics | CO₂eq (IPCC AR6 GWP), carbon intensity, EROI, renewable fraction |
| Biomass characterization | BiomassCharacterization | Proximate, ultimate analysis; HHV correlations |
| Biorefinery costing | BiorefineryCostEstimator | Equipment-level CAPEX/OPEX estimation |
| Biogas-to-grid chain | BiogasToGridModule | Pre-built: AD → upgrading → compression → grid |
| Gasification + FT | GasificationSynthesisModule | Pre-built: biomass → syngas → Fischer-Tropsch liquids |
| Waste-to-energy CHP | WasteToEnergyCHPModule | Pre-built: AD → gas engine with electrical + thermal output |
I-ter. Equipment Diagnostics & Reliability
| Capability | Implementation | Notes |
|---|
| Root cause analysis | RootCauseAnalyzer | Bayesian-inspired RCA with multi-source reliability priors |
| Symptom-based diagnosis | Symptom enum (12 symptoms) | TRIP, HIGH_VIBRATION, SURGE, FOULING, etc. |
| Hypothesis generation | HypothesisGenerator | Built-in libraries for compressor, pump, separator, HX, valve |
| Time-series evidence | EvidenceCollector | Trend, threshold, rate-of-change, correlation, multi-parameter pattern |
| Simulation verification | SimulationVerifier | Clone-perturb-compare with graduated severity |
| Reliability data | ReliabilityDataSource | IOGP/SINTEF, CCPS, IEEE 493, Lees, OREDA (9 sources, 4 CSVs) |
| Equipment failure modes | EquipmentFailureMode | MTBF/MTTR/failure rate calculations |
| Diagnostic reporting | RootCauseReport | JSON, text, ranked hypotheses with confidence scores |
| Custom hypothesis registry | HypothesisGenerator.register() | Domain-specific hypothesis extension |
Package: neqsim.process.diagnostics, neqsim.process.equipment.failure
J. Known Gaps and Limitations
Major Gaps (commonly requested but missing or incomplete)
| Gap | Description | Workaround |
|---|
| Rate-based distillation | No mass-transfer-rate column model | Use equilibrium stages with efficiency |
| Asphaltene modeling | Limited asphaltene precipitation | Use PC-SAFT with tuned parameters |
| Erosion modeling | No erosion rate calculation | API RP 14E velocity check only |
| Detailed heat exchanger design | TEMA-level design with Bell-Delaware, vibration, ASME VIII | Full thermal-hydraulic + mechanical via ShellAndTubeDesignCalculator |
| Dynamic simulation | Limited transient capability | runTransient() on ProcessSystem |
| Reservoir coupling | Simple reservoir only | No full reservoir simulator |
| Control system simulation | PID controllers + AlarmConfig + InstrumentScheduleGenerator + DynamicProcessHelper | No DCS/SIS emulation |
| Amine sweetening | Basic Kent-Eisenberg / DM | No rate-based amine model |
| Membrane separation | Basic membrane model | No detailed permeation |
| BWRS EOS | Only CH4 + C2H6 parameterized | Use SRK/PR instead |
| NACE MR0175 material selection | No systematic material logic | Manual standard lookup |
| Site-specific flare consequences | Point-source radiation, neutral Gaussian centerline dispersion, spherical noise, tip-Mach screening and API 537 flame geometry are available | Use validated specialist models for complex terrain/weather, toxic/combustion detail and final siting |
| API 2000 detailed vent sizing | Api2000TankVentingScreeningKernel aggregates caller-controlled normal/emergency demand and screens rated capacity/pressure; API demand tables/equations, vent area, device selection, and line losses are not implemented | Use the typed kernel for current-edition screening; retain licensed demand derivation and detailed device/network design externally |
|
EOS Limitations
| EOS | Known Limitation |
|---|
| SRK/PR | Poor near critical point; liquid density without volume correction |
| CPA | Slower convergence; limited component database for association |
| GERG-2008 | Only natural gas components (21 components) |
| PC-SAFT | Limited BIP database; slower than cubic EOS |
| BWRS | Only 2 components parameterized |
Component Database Limitations
| Component Type | Coverage |
|---|
| Light HCs (C1-C10) | ✅ Excellent |
| Heavy HCs (C11-C36) | ✅ Good (TBP fractions) |
| Common gases (N2, CO2, H2S, H2, O2) | ✅ Excellent |
| Water, MEG, methanol, TEG | ✅ Good (CPA parameterized) |
| Amines (MEA, DEA, MDEA) | ⚠️ Limited |
| Sulfur species (S8, SO2, COS) | ⚠️ Partial |
| Ionic species | ⚠️ Limited database |
| Polymers | ⚠️ Few PC-SAFT parameters |
| Refrigerants | ⚠️ Some available |
| Specialty chemicals | ❌ Case-by-case |
K. Reservoir & Production Properties
| Class | Purpose | Package |
|---|
GasPseudoCriticalProperties | Pseudo-critical T, P | pvtsimulation.reservoirproperties |
CompositionEstimation | Reservoir fluid estimation | pvtsimulation.reservoirproperties |
ZFactorCorrelations | Z-factor (Standing, DAK, etc.) | pvtsimulation.reservoirproperties |
SimpleReservoir | Material balance reservoir | process.equipment.reservoir |
Well | Well inflow model | process.equipment.well |
Quick Lookup: "Can NeqSim do X?"
| Question | Answer | Class/Method |
|---|
| Phase envelope? | ✅ | ops.calcPTphaseEnvelope() |
| Hydrate temperature? | ✅ | ops.hydrateEquilibriumTemperature() |
| Wax appearance? | ✅ | ops.calcWAT() |
| CO2 corrosion rate? | ✅ | DeWaardMilliamsCorrosion (screening); NorsokM506CorrosionRate / NorsokM506ElectrolyteBridge (rigorous, brine-driven) |
| H2S sour classification? | ✅ | DeWaardMilliamsCorrosion.isSourService() |
| Per-segment corrosion+scale profile? | ✅ | PipeSegmentIntegrity.fromPipe(...) |
| Flow-accelerated corrosion in a closed heating/cooling loop? | ✅ | FlowAcceleratedCorrosion (screening index; NORSOK M-506 does not apply to a CO2-free loop) |
| In-situ pH at operating temperature from a laboratory pH? | ✅ | AmineBufferedPH (DEA and MDEA buffers) |
| ISO 6976 calorific value? | ✅ | Standard_ISO6976 |
| Pipeline sizing? | ✅ | PipeBeggsAndBrills + PipelineMechanicalDesign |
| Compressor power? | ✅ | Compressor.getPower("kW") |
| NPV / DCF? | ✅ | DCFCalculator |
| Well casing design? | ✅ | WellDesignCalculator |
| TEG dehydration? | ✅ | SimpleTEGAbsorber |
| Sulfur deposition? | ✅ | SulfurDepositionAnalyser |
| JT cooling? | ✅ | ThrottlingValve |
| Depressurization? | ✅ | ProcessSystem.runTransient() |
| PSV sizing (gas / liquid, fire case)? |
L. Gap-Detection Protocol (for the Capability Scout — run in Step 1)
Use this map together with CHANGELOG_AGENT_NOTES.md before a task reaches
Step 2 (notebook analysis), so missing capability is discovered while the plan
is still cheap to change — not mid-simulation.
Classify every required capability
For each capability the task needs, classify against sections A–K and the
Known-Gaps table (section J):
| Verdict | Meaning | Action in Step 1 |
|---|
| ✅ Available | Class/method exists (found in this map or the source) | Cite the class; proceed |
| ⚠️ Partial | Exists but limited (see section J / EOS limitations) | Note the limitation; plan a workaround |
| 🔧 Workaround | Achievable by composing existing API | Document the recipe |
| ❌ Missing | Not in NeqSim (confirmed by source search) | Write a NIP in neqsim_improvements.md; decide extend-vs-defer NOW |
Emit a machine-readable readiness verdict (MANDATORY)
The Capability Scout MUST close capability_assessment.md with a single verdict
line so downstream agents (and the @review gate) can act on it:
capability_readiness: READY | READY_WITH_WORKAROUNDS | NEEDS_NIP | BLOCKED
- READY — every Critical capability is ✅ Available.
- READY_WITH_WORKAROUNDS — Critical capabilities are ✅/🔧; workarounds documented.
- NEEDS_NIP — a Critical/Important capability is ❌ Missing; NIP written, extend planned.
- BLOCKED — a Critical capability is ❌ Missing with no viable workaround or NIP path.
Verify before flagging (avoid false gaps)
Always confirm a suspected gap with a source search (grep_search /
file_search) before writing a NIP. This map is corrected as capabilities land —
e.g. two-phase PSV sizing (ReliefValveSizing.calculateTwoPhaseReliefArea,
API 520 omega method) is already present and must not be re-flagged as
missing. Confirmed partial capabilities (e.g. API 2000 screening without detailed vent sizing) are recorded in
section J; add newly confirmed gaps there so the next scout does not repeat the
search.
