Fuel & Operating Matrix
H2 Mole Fraction (X_H2)
0.30
Equivalence Ratio (φ)
0.65
Turbulence Intensity (u' / S_L)
3.50
Chamber Pressure (p, bar)
10.0 bar
Filtered Scalar Dissipation (Χ, s‾¹)
142.5 s⁻¹
Integral Length Scale Ratio (L / δ_L)
18.0
Turbulence-Chemistry Physics Framework: Formulated from Bray & Swaminathan (2011), Doan & Swaminathan (MILD DNS closures), Langella & Pitz unstrained-flamelet LES models, and Cambridge CARES high-pressure hydrogen stability data.
Combustion Regime (Borghi)
Thin Reaction Zones / Strained Flamelet
Kā > 1 & Da > 1 criterion
Turbulent Flame Speed Ratio
1.84
S_T / S_L closure model
Subgrid Scalar Variance
0.087
σ²_c LES subgrid unresolved fluctuation
MILD Autoignition Index
Distributed Ignition Fronts Active
Ignition vs flame front propagation
NOx Emission Index
2.4 g/kg (Suppressed Lean Premixed)
Thermal Zeldovich & prompt mechanism
Rayleigh Thermoacoustics
0.42 (Moderate Thermoacoustic Margin)
∫ p'q' dt coupling index
Borghi-Peters Combustion Diagram
Operating Point Marked
Horizontal: Length scale ratio (L/δL). Vertical: Velocity fluctuation ratio (u'/SL).
Strained Flamelet & Subgrid PDF
Reaction Rate Response
Filtered reaction rate Ωc versus reaction progress variable c across scalar dissipation Χ.
Turbulence-Chemistry Interaction Verification Matrix
Real-time Analytical Engine
Calculated using high-pressure strained flamelet closure formulations pioneered by Prof. Swaminathan (Cambridge). Microscopic reaction rates and heat release rates are filtered across LES subgrid cells with modeled β-PDF variance.
| Closure Parameter | Dimension / Symbol | Evaluated Value | Physical Consequence & Stability |
|---|---|---|---|
| Combustion Regime | Peters-Borghi Class | Thin Reaction Zones / Strained Flamelet | Kolmogorov eddies penetrate preheat zone; reaction sheet intact |
| Flame Speed Ratio | ST / SL | 1.84 | Turbulence flame wrinkling dilatation factor accounted |
| Subgrid Variance | σc2 | 0.087 | LES resolved scalar energy dissipation equilibrium |
| MILD Combustion Mode | Doan-Swaminathan Front | Distributed Ignition Fronts Active | Preheated reactants dilute thermal gradients; flameless behavior |
| NOx Emission Index | EINOx (g/kg fuel) | 2.4 g/kg (Suppressed Lean Premixed) | Suppressed thermal peak via low flame temperature & lean dilution |
| Acoustic Stability Index | Rayleigh Metric Margin | 0.42 (Moderate Thermoacoustic Margin) | Sub-critical heat-release-pressure phase synchronization |