气井零液流量可视化试验研究

零液流量气提流动是产水气井中一类独特的持液流动现象，是油管中由于微量液体长时间逐渐地积存形成了液柱，而气体流速又不足以将液体带出井筒所致，表现为井筒中存在2相流气提区，而井口处的液体流量为零。该现象气液2相流动滑脱损率为100%。其现场意义在于它相当于积液气井气举排水过程中始喷点的概念。给出该流动现象的压降和持液率计算数学模型，并设计建立总高为16ITI、内径040mm的可视化试验台架模拟该物理现象。试验采用先进测试手段采集得到其流型图片以及压降、井口压力、注气量、持液率等数据。通过理论计算与试验数据对比，验证该理论模型的正确性；给出算例，模拟计算实际气井零液流量气提流动和无滑脱气液2相流动，从而得出规律性认识。该研究成果对于指导严重积液气井气举排水采气设计以及优化注气量有积极的意义。

Visualized Experimental Study of Gas Well Zero Liquid Flow

Zero flow rate was one of the phenomena of gas lifting in gas well, which indicated the accumulation of minim liquid settling and formed a liquid column in a pipeline as the inadequate speed of gas flow could not bring it away. The slip ratio of this phenomenon is 100%. The mathematical model of liquid-holding rate and pressure were given and an imitation testing unit of 16- meter-high and o40-milimeter-ID was built up for visible testing. The flow patterns, pressure, wellhead pressure, gas injection and liquid holding rate were collected by using the advanced means. The comparison between theoretical calculation and testing data was made to validate the correctness of theoretical model. By using calculation sample, imitation calculation was made for actual zero flow-rate gas lifting flow and non-slip gas/liquid flow. This achievement has given the instruction to the design of heavy liquid accumulation gas well and to the optimization of gas injection rate.