CFD (SU2 & OpenFOAM)

@modelscript/cfd (languages/cfd) provides native WebAssembly GLR parsing, parametric configuration materialization, 3D CAD boundary marker synthesis, aerodynamic flow regime analysis, and cross-domain TGG synchronization for Computational Fluid Dynamics solver configurations.

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Supported Extensions & Dialects

Extension	Dialect	Description
.cfg, .su2	SU2 Configuration	Native Stanford University Unstructured (SU2_CFD) key-value & marker configuration
.cfgt	Parametric CFD Template	SU2 or OpenFOAM template supporting {{ expr }} parameter expressions
.cfd	OpenFOAM / Native CFD	OpenFOAM dictionary syntax (FoamFile, dimensions, internalField, boundaryField) and SU2 directives

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Parametric Template Materialization ({{ expr }})

CFD templates (.cfgt, .cfg, .cfd) can embed mathematical expressions in {{ ... }} blocks bound to SysML v2 or Modelica workspace parameters:

SOLVER= RANS
KIND_TURB_MODEL= SST
MACH_NUMBER= {{ cruise_speed / sqrt(1.4 * 287.05 * ambient_temp) }}
AOA= {{ angle_of_attack_deg }}
REYNOLDS_NUMBER= {{ rho_air * cruise_speed * chord_length / mu_air }}
MARKER_HEATFLUX= ( battery_plate, {{ heat_dissipation_watts / plate_area }} )

materializeCfdConfig(templateText, parameters) (languages/cfd/src/materializer.ts) evaluates each expression via evaluateCfdExpression, supporting arithmetic operators (+, -, *, /, ^), built-in math functions (sin, cos, tan, sqrt, abs, min, max, log, exp), and constants (PI, E).

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3D CAD Boundary Condition Synthesis

When a user assigns a fluid or thermal boundary condition to a 3D CAD face in the viewport, synthesizeCfdBoundary and applyBoundaryActionToConfig (languages/cfd/src/boundary-synthesizer.ts) synthesize and merge the appropriate directives for either SU2 or OpenFOAM:

Boundary Condition	SU2 Directive (.cfg / .su2)	OpenFOAM boundaryField Entry (.cfd)
Velocity / Total Inlet (inlet)	MARKER_INLET= ( <face>, <T_total>, <P_total>, <nx>, <ny>, <nz> )	type fixedValue; value uniform (<vx> <vy> <vz>);
Pressure Outlet (outlet)	MARKER_OUTLET= ( <face>, <back_pressure_Pa> )	type fixedValue; value uniform <pressure>;
Adiabatic / Heat-Flux Wall (wall)	MARKER_HEATFLUX= ( <face>, <heat_flux_W_m2> )	type noSlip; / type fixedGradient; gradient uniform <q>;
Isothermal Wall (isothermal)	MARKER_ISOTHERMAL= ( <face>, <temp_K> )	type fixedValue; value uniform <temp_K>;
Far-Field (farfield)	MARKER_FAR= ( <face> )	type freestream;
Symmetry Plane (symmetry)	MARKER_SYM= ( <face> )	type symmetryPlane;

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Aerodynamic Theory Slicing & Flow Regime Analysis

extractCfdSlicingProperties(text) (languages/cfd/src/language.ts) extracts aerodynamic coefficients directly from the CST:

• cd: Drag coefficient (DRAG_COEFF, CD, or C_D, default 0.3)
• refArea: Reference wetted/frontal area (REF_AREA, default 1.0 ${\text{m}}^2$)
• density: Freestream fluid density (FREESTREAM_DENSITY or RHO, default 1.225 ${\text{kg/m}}^3$)
• freeStreamVelocity: Freestream velocity (FREESTREAM_VELOCITY, default 30.0 $\text{m/s}$)

These properties feed directly into Modelica 1D aerodynamic drag models ($F_d=\frac{1}{2}\rho v^2{C}_d{A}_{\text{ref}}$), SysML v2 performance requirements, and the Multi-Domain Theory Coordinator (CaeContractOracle).

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Polyglot TGG Rules

@modelscript/cfd registers 6 bidirectional Triple Graph Grammar (TGG) rules in languages/cfd/src/language.ts:

Rule Name	Source (cfd)	Target Language	Target Construct
CfdDragPolarToModelicaParam	CfdConfig (cd, refArea)	modelica	ComponentClause (parameter Real Cd, A_ref)
CfdDragPolarToSysmlAttribute	CfdConfig (cd, refArea)	sysml2	AttributeUsage
CfdInletToModelicaFluidPort	Directive (MARKER_INLET)	modelica	ComponentClause (Modelica.Fluid.Interfaces.FluidPort_a)
CfdHeatFluxToModelicaHeatPort	Directive (MARKER_HEATFLUX)	modelica	ComponentClause (Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a)
CfdMarkerToSysmlPort	Directive (MARKER_*)	sysml2	PortUsage
CfdDirectiveToSysmlConstraint	Directive (MACH_NUMBER, REYNOLDS_NUMBER)	sysml2	ConstraintUsage

Command Line Interface (msx cfd)

msx cfd <action> [files...] [options]

Action	Description	Key Options
lint	Validates SU2 and OpenFOAM configuration syntax, boundary markers, and thermodynamic consistency.	—
summary	Prints turbulence model, freestream conditions, reference areas, and configured markers.	—
inspect	Dumps parsed marker tree, solver settings, and evaluated parametric expressions.	—
to-modelica	Generates Modelica 1D aerodynamic drag models (Modelica.Mechanics.Translational) and ports.	--out=<file.mo>
to-dae	Lowers boundary conditions and drag polar into ModelScript linear-memory DAE arena.	--out=<file.json>
solve	Invokes external or embedded SU2 flow solver iteration for steady/unsteady aerodynamic fields.	—

Examples

# Validate boundary markers and turbulence settings in an SU2 configuration
msx cfd lint transonic_wing.cfg

# Display mesh markers, Mach number, and reference area
msx cfd summary wing_template.cfgt

# Project aerodynamic drag polar to standard Modelica component
msx cfd to-modelica transonic_wing.cfg --out=AeroDrag.mo

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Diagnostic Rules

8 rules4 warning4 error Run with msx lint

Code	Rule	Severity	Message
C1001	cfl-stability-violation	warning	Courant-Friedrichs-Lewy stability number '<cfl>' exceeds recommended maximum limit for explicit scheme.
C1002	unresolved-mesh-file	error	Referenced grid mesh file '<mesh>' cannot be located or is invalid.
C1003	missing-inlet-boundary	warning	CFD domain '<name>' lacks a declared inlet boundary condition or stagnation state.
C1004	missing-outlet-boundary	warning	CFD domain '<name>' lacks a declared outlet boundary condition or pressure exit.
C1005	unphysical-freestream-mach	error	Freestream Mach number '<mach>' is non-physical or outside valid range [0, 25].
C1006	unphysical-reynolds-number	error	Freestream Reynolds number '<re>' must be strictly positive.
C1007	negative-surface-area	error	Aerodynamic reference area '<area>' must be strictly positive.
C1008	turbulent-viscosity-ratio	warning	Turbulent eddy viscosity ratio '<ratio>' is non-physical.

Generated from languages/cfd/src/errors.ts. All languages →