喷嘴轴线偏移对射流泵引射性能影响研究

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中图分类号：TE934 文献标识码：A DOI：10.12473/CPM.202411067

Abstract：Jet pumps are widely applied in production enhancement of gas wells in the Qingshimao region.In practices，jet pumps are commonly installed and lowered into welbores basedonexperience.Under hightemperatureand high-pressure conditions，however，this approach often leads toanofset betweenthe nozzleaxis andthe throataxisofjetpumps.To investigate theimpactofnon-coaxial alignmentbetweennozzleandthroatonjet pump performance，this study evaluatedthe jet pump's ejection performance，usingthe indicatorsof ejectioncoeficient and pressure loss coeficient，and through numerical simulation with the Realizable k-ε turbulence model. Specifically，changes in the ejection performance across a range of nozze-to-throat axis offset within 10%-60% （20 wereexamined，systematically revealing the influence of axis ofset on the ejection performanceof jet pump．The results indicate that as the nozzle axis ofset increases，the jet pump's ejection performance gradually declines. When the nozzleaxis deviated toward the upper wallsurface，the maximumvelocityof the working fluid at the nozzle outlet dropped by 5.3% ，while the dynamic pressure of the fluid on the upper wall surfaces of the throat and difuserincreased，enhancing the mixing efectbetweenthe working fluidandtheejected fluid.Conversely，the lower wall surfaces of the throat and diffuser exhibited opposite trends.At a 10% offset，mixed fluid recirculation and localized turbulence emerged on the lower diffuser wall，causing a 7.8% decrease in the ejection coefficient anda 0.5% increase in the pressure loss coefficient.Ata 40% offset，localized turbulence appeared on the lower throat wall，resulting in a 23.9% drop in the ejection coefficient and a 1. 2% rise in the pressure loss coefficient. Asthe offset further increased，the mixed fluid recirculation zone and localized turbulence zone continued to expand.This study provides atheoretical basis for evaluating the performanceof jet pumps under actual operating conditions and offers reference criteria for engineering optimization.

Keywords：jet pump；nozle axis offset；ejection coefficient；pressure loss；flow field analysis； k -εturbulence model;inlet dynamic pressure

0 引言

射流泵是一种以高速流体作为工作介质，利用湍射流的紊动扩散作用来抽吸、混合和输送低速流体的流体机械与混合反应设备[1-2]，具有结构简单、加工成本低、密闭性好等优点，在气井的排水、采气、清砂等增产作业中得到了广泛应用[3-5]

根据射流泵喷嘴和吸入室位置的不同，射流泵分为中心射流泵和环形射流泵[6-8]。（剩余10468字）