Cantera Chemical Kinetics & Thermochemistry (.yaml, .cti)

@modelscript/cantera (languages/cantera) provides native WebAssembly parsing, NASA-7 polynomial thermodynamic evaluation ($C_p^{\circ }(T)$, $H^{\circ }(T)$, $S^{\circ }(T)$, $G^{\circ }(T)$), modified Arrhenius and Troe falloff reaction rate calculation, non-isothermal batch reactor ODE integration, DAEBuilder lowering, and SBML / Modelica projections for Cantera gas-phase combustion, catalysis, and chemical kinetics mechanisms.

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Supported Extensions & Standards

Extension	Format	Description
.yaml	Cantera YAML	Modern Cantera 2.5+ / 3.x YAML mechanism format (phases, species, reactions, thermo: NASA7)
.cti	Legacy Cantera CTI	Classic Cantera ideal_gas, species, and reaction mechanism definitions

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Key Capabilities

1. NASA-7 Thermochemical Polynomials

• Evaluates two-range (low-$T$ / high-$T$) 7-coefficient NASA polynomials for every species:$$\frac{C_p^{\circ }(T)}{R}=a_0+a_{1}T+a_2{T}^2+a_3{T}^3+a_4{T}^4$$$$\frac{H^{\circ }(T)}{RT}=a_0+\frac{a_1}{2}T+\frac{a_2}{3}{T}^2+\frac{a_3}{4}{T}^3+\frac{a_4}{5}{T}^4+\frac{a_5}{T}$$$$\frac{S^{\circ }(T)}{R}=a_0\ln T+a_{1}T+\frac{a_2}{2}{T}^2+\frac{a_3}{3}{T}^3+\frac{a_4}{4}{T}^4+a_6$$
• Verifies continuity of $C_p^{\circ }$, $H^{\circ }$, and $S^{\circ }$ across the midpoint splitting temperature $T_{\text{mid}}$.

2. Elementary, Three-Body & Troe Falloff Kinetics

• Computes forward and reverse rate constants via modified Arrhenius expressions and thermodynamic equilibrium constants $K_c(T)=\exp (-\mathrm{\Delta }{G}^{\circ }/RT)$:$$k_f(T)=A{T}^{\beta }\exp (-\frac{E_a}{RT})$$
• Supports third-body collision efficiencies (+ M) and pressure-dependent Lindemann / Troe falloff formulations.

3. Batch Reactor ODE Solver & DAE Lowering

• Integrates constant-volume or constant-pressure gas-phase reactor species and temperature evolution and lowers the kinetic network into @modelscript/runtime's DAEBuilder arena, Modelica 3.x, or SBML.

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Pre-Flight Diagnostics

10 rules7 error3 warning

Code	Rule	Severity	Message
M9201	element-balance-violation	error	Reaction '<equation>' is not elementally balanced for element '<element>' (reactants: <reactantCount>, products: <productCount>).
M9202	charge-balance-violation	error	Reaction '<equation>' violates net electrical charge conservation (reactants: <reactantCharge>, products: <productCharge>).
M9203	undeclared-phase-species	error	Reaction or phase '<equationOrPhase>' references species '<speciesName>' not declared in the mechanism species list.
M9204	nasa7-temperature-discontinuity	warning	Species '<speciesName>' NASA-7 polynomial has a '<propName>' discontinuity (<value>) at midpoint temperature '<Tmid>' K.
M9205	invalid-nasa7-temperature-bounds	error	Species '<speciesName>' specifies invalid NASA-7 temperature bounds [<Tmin>, <Tmid>, <Tmax>] K.
M9206	negative-pre-exponential-factor	error	Reaction '<equation>' specifies a non-positive pre-exponential factor '<A>'.
M9207	missing-falloff-low-pressure-limit	error	Falloff reaction '<equation>' is missing required 'low-P-rate-constant' definition.
M9208	duplicate-reaction-declaration	warning	Identical non-duplicate reaction '<equation>' is declared multiple times without 'duplicate: true'.
M9209	negative-third-body-efficiency	error	Third-body efficiency for '<speciesName>' in reaction '<equation>' is negative (<efficiency>).
M9210	missing-species-thermo	warning	Species '<speciesName>' is missing a 'thermo' polynomial definition.

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

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CLI Usage

# Validate elemental balance, NASA-7 continuity, and Arrhenius parameters
msx lint H2Combustion.yaml

# Parse and inspect the Cantera mechanism structure
msx parse H2Combustion.yaml