浸没式气体喷吹进入液体中引起复杂多相流动,其中喷嘴的结构对压降方面的操作费用至关重要.本文使用了具有圆形、齿轮状和四叶截面形状的喷嘴结构,研究了不同气体流量和溶池深度下喷嘴结构对喷嘴进出口间压降的影响.结果表明,除喷孔出口处水力直径外,喷孔出口处面积和周长也对压降有重要作用.对于相同的气相表观气速,四叶形几何结构条件下的平均压降最小.溶池深度对压降的影响可以忽略不计.提出了一个与压力降相关的修正欧拉数的经验式,该式取决于喷嘴结构参数AoL-2o和特征长度为水力直径do的修正弗劳德数gd5oQ-2.
Submerged gas injection into liquid leads to complex multiphase flow, in which nozzle geometries are crucial important for the operational expenditure in terms of pressure drop. The influence of the nozzle geometry on pressure drop between nozzle inlet and outlet has been experimentally studied for different gas flow rates and bath depths. Nozzles with circular, gear-like and four-leaf cross-sectional shape have been studied. The results indicate that, besides the hydraulic diameter of the outlet, the orifice area and the perimeter of the nozzle tip also play significant roles. For the same superficial gas velocity, the average pressure drop from the four-leaf-shaped geometry is the least. The influence of bath depth was found negligible. A correlation for the modified Euler number considering the pressure drop is proposed depending on nozzle geometric parameter2ooAL-and on the modified Froude number52ogdQ-with the hydraulic diameter of the nozzledo as characteristic length.