Gas Turbine Combustor: Swirl Flame Stabilization (2D)

This is the 2D-native counterpart to the 3D swirl-combustor simulator. Rather than orbiting a rendered particle cloud around the duct axis, it draws the axisymmetric meridional (x–r) cross-section directly — the natural plane for this flow, since nothing about the physics depends on the azimuthal angle — with unburned mixture and hot products tracked as they pass through the central toroidal recirculation zone (CTRZ) that a swirler's vortex breakdown creates. Alongside it sits a live operating map plotting every combination of equivalence ratio and inlet velocity into stable, lean-blowout or flashback regions at the current vane angle, and the laminar flame-speed curve itself with the current mixture marked on it. All three panels share the exact same swirl-number, Damköhler-number and flame-speed formulas as the 3D version; sweeping the full slider range against those formulas surfaced a real bug in the 3D source — its flashback threshold is mathematically unreachable across the whole control range — which this version fixes by scaling the turbulent flame-speed enhancement with the swirl number instead of using a flat multiplier.