In the charcoal block reduction test with a blowpipe one often will oxidize the probe in the first step to get rid of nonmetal elements in the probe, and then will use the reduction flame to reduce oxidic metal compounds in the melt to the elemental metal.
Reaction rate parameters were varied in order to provide the best agreement between computed and experimentally observed flame speeds in selected mixtures of fuel and air.Dependences of the rate and intensity of light flashes on pressure, temperature, and contact time are studied.An interpretation of the observed phenomenon is given.The largest contribution of remaining hydrocarbons are those leaving the crevice at temperatures below 1400 K.Simplified reaction mechanisms for the oxidation of hydrocarbon fuels have been examined using a numerical laminar flame model.Two-step and quasi-global approaches also yield information on flame temperature and burned gas composition.
However, none of the simplified mechanisms studied accurately describes the chemical structure of the flame itself.
ABSTRACT: Low temperature combustion (LTC) has been considered as a promising combustion technology in internal combustion engine due to its higher thermal efficiency and lower emission than the conventional combustion engines.
to 0.05 in a two-stage atmospheric-pressure combustion system in which soot-laden gas from a primary flame was partially cooled, mixed with oxygen-containing gas, and burned in a downstream premixed flame.
The average value of the collision efficiency of OH with soot is found to be 0.28 if the optical (equivalent sphere) diameter of the soot aggregates is used in the calculations, or about 0.13 if the diameter of the individual spherical units within the aggregates is used.
The actual value of the collision efficiency is expected to be bounded by these two values.
Simulation results show that the post-flame oxidation process takes place within a reactive layer where intermediate hydrocarbon products are formed at temperatures above 1100-1200 K, followed by a carbon monoxide conversion region closer to the hot burned gases.