Stabilization mechanism revelation of a novel vortex-tube combustion technique: LES with <i>sgs-pdf</i> approach

The paper revealed the in-depth stabilization mechanisms of a novel vortex-tube combustion technique by using ethanol as fuel, which is implemented stratified combustor (SVC). stability properties SVC are investigated, showing that has wide limit and low-pressure fluctuation amplitudes with uniform flame front. equivalence ratio at lean flammability always below 0.2, amplitude pressure less than 2000 Pa, indicating highly steady process. non-premixed structure guarantees high mass concentrations near reaction zone, while vortex flow also decreases local velocity, inhibiting blow-out, thus providing good self-adjusting capacity under various global ratios. vortex–flame interaction transports interior high-enthalpy burnt gas to exterior unburnt region, thereby promoting ignition. transported front where it promotes yields an intensified combustion. large tangential velocity density gradient result in values Richardson number, suggests laminarization occurs results aero-dynamic thermo-dynamic stabilities. small Rayleigh number indicate flame-dynamic stability. Therefore, resultant three types dynamic stabilities intrinsic causes ultra-steady process this combustor.