Exchange coefficients and mathematical modelsof jet-diffusion flames

摘要: Complete mathematical models for the calculation of flow and temperature fields turbulent flames their combustion chambers are still not available. They could be obtained from calculations heat exchange, instance, by nonluminiscent radiation, a description field. The principle lack, at this time, is method computing exchange momentum,mass, heat. In present paper, coefficients momentum, matter, have been measurements. Attempts also made to derive unmixedness values turbulence-measurements data, since unmixedness, as well determines reaction rate. Transport momentum derived both time mean velocity fluctuating microscale. Results these in good agreement, order magnitude coefficient was 10–30×10−3 m2/sec. increase enclosed jets with onset recirculation zone. depend on nozzle diameter velocity. turbulence relation between rates mixingand given that based assumption rate increases intensity decreases scale. An empirical formula local flame axis which covers data concentrations, excepted first part jet where very special conditions exist cannot expected cover.