真空吸力作用流体的流型及压降试验研究

设计了一套室内研究真空吸力作用下流体流型及压降规律的实验装置，通过实验，提出真空吸力在不同条件下管内流体存在单相水流、单相气流和气水两相流三种流型；贮水瓶内水位单相水流时上升、单相气流不变、气液两相流下降或不变；真空吸力作用下管内流体的真空度沿流动方向变化，垂直上升流体不同流型压降梯度不等；真空预压地基负压作用流体的流型为气液两相流、地下水位下降符合工程实际，真空预压地基内没有负的超孔隙水压力，该实验装置可清楚地看到管内流体的流型及运动特征．实验装置简单．可为研究真空预压地基内流体运动规律提供室内实验条件。

Experimental Study on Flow Pattern and Pressure Drop of Fluid under Suction

A set experimental device,which can carry out laboratorial research about flow pattern and pressure drop law under suction is designed.Based on analysis and discussion about experimental phenomenon and experimental results,the following conclusions are drawn.There are three flow patterns to fluid under the action of suction in different conditions:water single-phase flow,air-water two-phase flow,air single-phase flow.The water level is ascending when water single-phase flow in store water bottle,and immobile when air single-phase flow,and descending when two-phase flow.Vacuum pressures are changed along flow direction,and ascending fluid's average pressure falls are unequal in different flow pattern.Fluid's flow pattern is air-water two-phase flow under the action of suction and groundwater descends that accord with project practice,and there isn't negative exceeding pore water pressure in vacuum preloading ground.Flow pattern and flow character are distinctly seen in pipeline,and experiment device is simple and redone easily.It can provide experimental condition to research flow rule of fluid in vacuum preloading ground.