Energy Dissipative Plunging Flows

The analysis of plunging flows using energy dissipation hypothesis is presented in this paper. The classic two-control-volume theory has recently been found questionable and needs to be corrected. In this study, we avoid the questionable part of that framework and use a single control volume for the analysis of plunging flows. Furthermore, we hypothesize that the increase in kinetic energy in the underflow and entrained flow should be no greater than the loss in potential energy as the inflow plunges. In the current framework, the entrained flow rate does not exceed approximately 40% of the total inflow rate. The densimetric Froude number at the plunge point, Fdp = q/, where q = inflow rate per unit width; g′ = reduced gravity of inflow; and Hp = flow depth at the plunge point, is typically in the range of 0.3相似文献   

Gas Transfer During Bubbler Destratification of Reservoirs

In this paper, dimensional analysis has been carried out to derive general equations that predict: the total gas transferred to the ambient reservoir water from an air bubbler, total volume entrained, and total energy consumed for a known or equivalent linear stratification. The equations are tested by comparison with a one-dimensional bubbler model developed by the authors. It is shown that the oxygen transfer to the water column can be significant if small bubbles are used. The mechanical destratification efficiency ηmech (%), destratification time per unit surface area Γ?(s/m2), oxygen dissolution efficiency Ω (%), and oxygen transferred per unit input energy are examined as functions of bubble size. It is concluded that an average bubble radius of 1?mm should be considered for design purposes. However, if oxygen transfer from the bubbler is not considered important, then a bubble size of up to 4?mm is acceptable for destratification purposes.     

Acid-Gas Storage in a Deep Saline Aquifer: Numerical Sensitivity Study to Evaluate Parameter and Model Uncertainty

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地震技术在隐蔽油气藏勘探中的应用

应用地震相分析、波阻抗反演和神经网络技术,分别对小洼油田和陈家洼陷的隐蔽油气藏进行了识别和预测.其结果新增石油地质储量分别为1 400×104 t和1 500×104t,取得了很好的勘探效果.     

木头断块油田稳产上产的基本经验和历程

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非离子表面活性剂NS在文明寨油砂和岩心上的吸附

针对高温、高矿化度、高钙镁含量的中原文明寨油田，筛选出了非离子表面活性剂ＮＳ体系作为驱油剂。本文报道了ＮＳ在文明寨油藏油砂和岩心上的静、动态吸附实验结果。     

SPA淀粉接枝共聚物堵水调剖剂性能研究

针对中原油田含盐量高的地层特点，开发出了以淀粉与丙烯酰胺接枝共聚物SPA、有机复合交联剂MC和促凝剂L为主要成分的堵水调剖剂。研究了该堵水调剖剂各组分浓度对成胶时间与凝胶粘度的影响，考察了pH值、温度、水质及剪切作用对堵水调剖剂性能的影响，采用岩心模拟试验方法评价了该堵水调剖剂的作用效果。结果表明，SPA-WC-L堵水调剖剂强度高、耐冲刷，具有良好的选择性堵水作用，可满足中原油田堵水调剖作业的需要。     

泡沫酸酸化在文明寨油田的应用

本文针对文明寨油井段长,渗透率高,层间矛盾突出,井况恶化,油井负压等特点,采用泡沫酸酸化工艺解除油层污染,实现泡沫暂堵高渗层,沁沫负压排酸,恢复井产能,改善水驱开效果。     

低渗注水油田地层结垢的防治技术

在油田注水过程中，水的不相容性会造成地层结垢。本文研究了油田注水地层结垢的化学防治技术，并根据矿场应用实例，对其效果进行了评价和分析。