在小型燃烧室内压力雾化旋流燃烧过程的数值模拟

Numerical Simulation on Swirl Combustion of Pressure Atomized Spray in Small Chamber

利用概率密度函数模型(PDF),针对不同供油压力和喷雾锥角下压力旋流雾化喷嘴出口下游液滴群在小型燃烧室内的燃烧过程进行数值模拟研究。研究表明:随着喷雾锥角的增加,火焰张角有所增大,火焰中心及火焰区域外的燃烧室空间温度逐渐上升。燃烧室单侧出口导致了火焰偏斜,且随喷雾锥角增加而越发明显,适当增加喷嘴供油压力可改善远出口端的温度分布。本文研究的压力雾化喷嘴,在小型燃烧室内喷雾锥角=60～80°、供油压力=0.9 MPa～1.2 MPa时可以取得较好的燃烧效果。

The numerical simulation aim to analyze oil droplets’combustion process in the combustion chamber after jetting from pressure swirl atomized nozzles using PDF model.These nozzles are designed to operate at different oil pressure and with different spray cone angle.Studies show that the flame expands in radial direction and cause the rise of temperature in the flame center and outside the flame.Besides,boring only in one side of the chamber will induce flame deflection and this tendency will increase with the increment of the spray core angle.Augmenting oil supply pressure will improve the temperature distribution near the outlet.Finally,the nozzle operating under the oil pressure from 0.9 to 1.2 MPa and with a spray cone angle between 60 and 80 degree will produce an efficient flame.