円筒形燃焼炉内の噴流拡散火炎の燃焼特性に関する研究 : 第3報,NO_x排出特性に対する流れ場の影響(熱工学,内燃機関,動力など)

概要

論文の詳細を見る
Velocity measurements in cylindrical combustion furnaces have been conducted to clarify the effect of flow field on the emission index of NO_x, EINO_x. Propane jet nonpremixed flames were formed on a fuel nozzle surrounded by two air nozzles. The EINO_x roughly decreases with the global equivalence ratio φ, the inner diameter of the furnace D_1, and the turbulence at the flame boundary created by the air velocity difference AUa. Distributions of velocity obtained by LDV measurements have verified a large vortex at the bottom of furnace, leading to the entrainment of burned gas to the flame. The size and strength of the vortex are increased by the turbulence at the flame boundary. The recirculation vortex becomes larger in the axial direction with the increases in φ and D_1. The increase in 0 induces the decrease in the oxygen concentration of the burned gas. Consequently, the decrease in EINO_x with these parameters has been caused by the dilution of flame by the burned gas entrained by the recirculation vortex and by the flame stretch attributable to the turbulence increased with ΔU_a and φ.
2008-03-25