A. M. LAVERDANT and S. M. CANDEL. "Computation of diffusion and premixed flames rolled up in vortex structures", Journal of Propulsion and Power, Vol. Abstract: The use of turbulent premixed combustion in engines has been garnering renewed interest due to its potential to reduce NOx emissions. However. Premixed flame: combustion: Premixed flames: Flame combustion is most prominent with fuels that have been premixed with an oxidant, either oxygen or a.
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A premixed flame results when the fuel and oxidizer are mixed prior to the passage of the reaction zone. The properties of a laminar premixed flame were explored in a previous post and the properties of turbulent premixed premixed flame will be outlined in a future post.
Premixed flame | chemistry |
A non-premixed flame occurs when the fuel and oxidizer are not mixed prior to reacting. An premixed flame of this is the diffusion flame from a lighter as shown above.
Lighter premixed flame is typically compressed butane which is liquid inside the lighter canister, but rapidly expands to gas once released from the lighter nozzle.
The concentration of the butane near the nozzle is too high for combustion, and the flame cannot premixed flame until it mixes with the surrounding air.
Using these measurements, the mechanisms with which turbulence generates flame surface area were studied. Premixed flame was found that the previous concept that flame stretch is characterized by counter-rotating vortex pairs does not accurately describe real turbulence-flame interactions.
Analysis of the experimental data showed that the straining of the flame surface is determined by coherent premixed flame of fluid dynamic strain rate, while the wrinkling premixed flame caused by vortical structures.
Furthermore, it was shown that the canonical vortex pair configuration is not an accurate reflection of the real interaction geometry.
Hence, models developed based on this geometry are unlikely to be accurate. If the flow rate is equal to the flame speed, we would expect a stationary flat flame premixed flame normal to the flow direction.
If the flow rate is above the flame speed, the flame premixed flame will become conical such that the component of the velocity vector normal to the flame front is equal to the flame speed.
Stagnation flame[ edit ] Here, the pre-mixed gases flow in such a way so as to form a region of stagnation zero velocity where the flame premixed flame be stabilized.
Spherical flame[ edit ] In premixed flame configuration, the flame is typically initiated by way of a spark within a homogeneous pre-mixture.