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应用二维激光多普勒仪(LDV)对一种单柱单锥型液-液旋流分离管内流场进行了测量,考察了流量、溢流比、压力比和气芯等参数对流场的影响。测量结果表明:切向速度分布呈典型的Rankine涡结构,沿轴向衰减很少,表明所用锥角是合适的;因该旋流管的水力直径较大,切向速度的总体水平较低,由此对了离特性带来不利影响。此外,没有观察到切向速度分布的双峰分布现象。轴向速度的总体水平较低,尤其是在锥形管的上游更为明显,这既有助于增加液流在旋流管中的停留时间,改善了离特性,也有利于降低压力损失,改善旋流管的低阻特性;雷诺应力总体上呈近轴与近壁处大,其它区域中小的分布趋势;上游的轴向正应力大于切向正应力,而下游的切向正应力又大于轴向正应力,表明其中湍流的各向异性特性;在所考察的四种工况因素中,以流量的影响范围和程度最大,压力比、溢流比及气芯的影响仅表现在近轴区中。
A two-dimensional laser Doppler (LDV) was used to measure the flow field in a single-column single cone liquid-liquid cyclone separation tube. The effects of flow rate, overflow ratio, pressure ratio and air core on the flow field influences. The results show that the tangential velocity distribution is a typical Rankine vortex with little attenuation in the axial direction, which indicates that the taper angle used is suitable. Because of the larger hydraulic diameter and lower overall tangential velocity, As a result, it has an adverse effect on the characteristics. In addition, no bimodal distribution of tangential velocity distribution was observed. The lower overall level of axial velocity, especially upstream of the conical tube, helps both to increase the residence time of the liquid flow in the cyclone, to improve the separation characteristics and to reduce the pressure loss, The Reynolds stress is generally large at the paraxial and near wall, and small to medium distribution in other regions; the axial normal stress in the upper reaches is greater than the normal stress in the tangential direction, and the positive tangential stress in the downstream is greater than Axial normal stress, which shows the turbulent anisotropy of the characteristics of the four working conditions in the factors considered in the flow range and extent of the greatest impact, pressure ratio, overflow ratio and the impact of air core only in the paraxial District.