表面活性剂体系下气液两相螺旋流压降规律实验研究

Experimental Study of the Influences of Surfactants on Pressure Drop in Two-phase Spiral Flow in Horizontal Pipe

通过气液两相螺旋流实验仪器研究了可降解性表面活性剂对气液两相流流型和压降的影响,实验介质设定为空气和水,表面活性剂为天然椰子油,气液两相折算速度0.1~4.0 m/s,体积含气率5%~95%,起旋器为叶轮,实验在室温下进行。实验得到了螺旋泡状流、螺旋线状流、螺旋轴状流、螺旋团状流、螺旋弥散流、螺旋波状分层流等6种典型流型。对实验数据进行分析整理,发现流型对压降起着至关重要的作用,其中螺旋弥散流的压降梯度最小,螺旋波状分层流的压降梯度最大。同时分析了起旋器、含气率、表面活性剂浓度对压降的影响。另外,提出了对于由叶轮起旋的气液两相螺旋流的摩擦压降新的预测公式,理论计算值与实验所得数据吻合良好。

The influences of biodegradability surfactant on gas - liquid two - phase spiral flow in horizontal pipe were investigated experimentally, in which the experimental medium was supposed to be air and water, worked at room tem- perature, the gas volume fraction was 5%-95%, gas and liquid superficial velocity was 0. 1 -4.0 m/s, surfactants used were biodegradability coconut oil extracted from plants and rotary device used was impeller. Flow patterns were di- vided into six parts： spiral bubbly flow, spiral linear flow, spiral slug flow, spiral axial flow, spiral dispersed flow and spiral wave stratified flow. The analysis of the experimental data found flow pattern played a vital role in pressure drop, the pressure drop gradient of spiral dispersed flow is least and that of the spiral wave stratified flow is the maximum. At the same time, the influences of rotary device, gas volume fraction and surfactant on pressure drop were investigated too. In addition, it is put forward the new prediction formula about the friction pressure drop of gas - liquid two - phase spiral flow generated by vane and the result showed that the theoretical value accorded well with the experimental value.