Prediction of Sedimentary Microfacies Distribution by Coupling Stochastic Modeling Method in Oil and Gas Energy Resource Exploitation

In view of the problem that a single modeling method cannot predict the distribution of microfacies, a new idea of coupling modeling method to comprehensively predict the distribution of sedimentary microfacies was proposed, breaking the tradition that different sedimentary microfacies used the same modeling method in the past. Because different sedimentary microfacies have different distribution characteristics and geometric shapes, it is more accurate to select different simulation methods for prediction. In this paper, the coupling modeling method was to establish the distribution of sedimentary microfacies with simple geometry through the point indicating process simulation, and then predict the microfacies with complex spatial distribution through the sequential indicator simulation method. Taking the DC block of Bohai basin as an example, a high-precision reservoir sedimentary microfacies model was established by the above coupling modeling method, and the model verification results showed that the sedimentary microfacies model had a high consistency with the underground. The coupling microfacies modeling method had higher accuracy and reliability than the traditional modeling method, which provided a new idea for the prediction of sedimentary microfacies.

Silicone oil migrating into the conjunctival space and orbit after surgery for an eye-penetrating injury:A case report

BACKGROUND We report a case of eye-penetrating injury in which a massive silicone oil migration into the patient’s subconjunctival space and orbit occurred after vitrectomy.CASE SUMMARY A 30-year-old male patient sought medical attention at Ganzhou People’s Hospital after experiencing pain and vision loss in his left eye due to a nail wound on December 9,2023.Diagnosis of penetrating injury caused by magnetic foreign body retention in the left eye and hospitalization for treatment.On December 9,2023,pars plana vitrectomy was performed on the left eye for intraocular foreign body removal,abnormal crystal extraction,retinal photocoagulation.Owing to the discovery of retinal detachment at the posterior pole during surgery,silicone oil was injected to fill the vitreous body,following which upper conjunctival bubble-like swelling was observed.Postoperative orbital computed tomography(CT)review indicated migration of silicone oil to the subconjunctival space and orbit through a self-permeable outlet.On December 18,2023,the patient sought treatment at the First Affiliated Hospital of Nanchang University,China.The patient presented with a pronounced foreign body sensation following left eye surgery.On December 20,2023,the foreign body was removed from the left eye frame and an intraocular examination was conducted.The posterior scleral tear had closed,leading to termination of the surgical procedure following supplementary laser treatment around the tear.The patient reported a significant reduction in ocular surface symptoms just one day after surgery.Furthermore,a notable decrease in the migration of silicone oil was observed in orbital CT scans.CONCLUSION The timing of silicone oil injection for an eye-penetrating injury should be carefully evaluated to avoid the possibility of silicone oil migration.

Benefits of Dielectric Oil Regeneration Systems in Power Transmission Networks: A Case Study

The criticality of transformers and reactors in the power transmission network and the paramount importance of ensuring their reliability through maintenance of the insulating oil is known. This paper presents a comprehensive examination of the efficacy and economic viability of a dielectric oil regeneration system, as implemented by the Transmission System Maintenance Department (TSMD) of the Independent Power Transmission Operator (IPTO), Greece’s sole transmission operator. Through a detailed chemical analysis and performance evaluation, we assess the impact of the regeneration system on treated insulating oil quality over multiple cycles. The study reveals that the electrical properties of the insulating oil are fully restored after regeneration, negating the need to fully replace it, while the investment becomes cost-neutral within weeks from the commissioning of the regeneration system. This economic analysis, coupled with the system’s environmental benefits of reducing waste oil generation, positions the dielectric oil regeneration system as a compelling solution for the maintenance of power transmission assets.

Multistring analysis of wellhead movement and uncemented casing strength in offshore oil and gas wells

This paper presents a theoretical method and a finite element method to describe wellhead movement and uncemented casing strength in offshore oil and gas wells.Parameters considered in the theoretical method include operating load during drilling and completion and the temperature field,pressure field and the end effect of pressure during gas production.The finite element method for multistring analysis is developed to simulate random contact between casings.The relevant finite element analysis scheme is also presented according to the actual procedures of drilling,completion and gas production.Finally,field cases are presented and analyzed using the proposed methods.These are four offshore wells in the South China Sea.The calculated wellhead growths during gas production are compared with measured values.The results show that the wellhead subsides during drilling and completion and grows up during gas production.The theoretical and finite element solutions for wellhead growth are in good agreement with measured values and the deviations of calculation are within 10％.The maximum von Mises stress on the uncemented intermediate casing occurs during the running of the oil tube.The maximum von Mises stress on the uncemented production casing,calculated with the theoretical method occurs at removing the blow-out-preventer （BOP） while that calculated with the finite element method occurs at gas production.Finite element solutions for von Mises stress are recommended and the uncemented casings of four wells satisfy strength requirements.

Heating of heavy oil by circulating hot water in closed double casing in ultra-deep wells

In heavy oil production,the loss of energy to ambient surroundings decreases the temperature of the heavy oil flowing upwards in a vertical wellbore,which increases the oil viscosity and the oil may not flow normally in the wellbore.Therefore,it is necessary to lower the heavy oil viscosity by heating methods to allow it to be lifted easily.Heating of heavy oil in an oil well is achieved by circulating hot water in annuli in the well（tubing-casing annulus,casing-casing annulus）.In this paper,based on heat transfer principles and fluid flow theory,a model is developed for produced fluids and hot water flowing in a vertical wellbore.The temperature and pressure of produced fluids and hot water in the wellbore are calculated and the effect of hot water on heavy oil temperature is analyzed.Calculated results show that the hot water circulating in the annuli may effectively heat the heavy oil in the tubing,so as to significantly reduce both oil viscosity and resistance to oil flow.

Three-Dimensional Finite Element Numerical Simulation and Physical Experiment for Magnetism-Stress Detecting in Oil Casing

The casing damage has been a big problem in oilfield production. The current detection methods mostly are used after casing damage, which is not very effective. With the rapid development of China's offshore oil industry, the number of offshore oil wells is becoming larger and larger. Because the cost of offshore oil well is very high, the casing damage will cause huge economic losses. What's more, it can also bring serious pollution to marine environment. So the effective methods of detecting casing damage are required badly. The accumulation of stress is the main reason for the casing damage. Magnetic anisotropy technique based on counter magnetostriction effect can detect the stress of casing in real time and help us to find out the hidden dangers in time. It is essential for us to prevent the casing damage from occurring. However, such technique is still in the development stage. Previous studies mostly got the relationship between stress and magnetic signals by physical experiment, and the study of physical mechanism in relative magnetic permeability connecting the stress and magnetic signals is rarely reported. The present paper uses the ANSYS to do the three-dimensional finite element numerical simulation to study how the relative magnetic permeability works for the oil casing model. We find that the quantitative relationship between the stress' s variation and magnetic induction intensity's variation is: Δδ =K* ΔB, K = 8.04×109, which is proved correct by physical experiment.

Numerical simulation of oil shale in-situ mining using fluid-thermo-solid coupling

For the in-situ gas-injection mining technology of oil shale by process,a numerical simulation method with flow-thermo-solid coupling is proposed in this paper.This method adopts separate simulations and step-by-step coupling simulation ideas combined with the advantages of the finite element method and the finite volume method.The numerical simulation of flow-thermo-solid coupling is decomposed into two parts:flow-solid coupling and thermo-solid coupling.Considering the Fuyu oil shale in-situ production test area in Songliao Basin as an example,it is concluded that the oil shale has undergone four heating stages:a rapid temperature rise,a steady temperature rise,a slow temperature rise,and heat preservation.It takes about 10 years for the stress-strain state of the oil shale layer to reach a steady-state through the thermo-solid coupling.The main strain zones of the oil shale layer are distributed near the fracturing fractures connected to the gas injection well and at the edge of the fracturing fractures.The areas with the plastic deformation in the oil shale layer predominantly appear near the gas injection wells,production wells,and fracturing channels.The areas with the largest fracture strength are mostly distributed near the edge of the fracturing fractures with low flow velocity and low temperature.

Proppant transport in rough fractures of unconventional oil and gas reservoirs

A method to generate fractures with rough surfaces was proposed according to the fractal interpolation theory.Considering the particle-particle,particle-wall and particle-fluid interactions,a proppant-fracturing fluid two-phase flow model based on computational fluid dynamics(CFD)-discrete element method(DEM)coupling was established.The simulation results were verified with relevant experimental data.It was proved that the model can match transport and accumulation of proppants in rough fractures well.Several cases of numerical simulations were carried out.Compared with proppant transport in smooth flat fractures,bulge on the rough fracture wall affects transport and settlement of proppants significantly in proppant transportation in rough fractures.The higher the roughness of fracture,the faster the settlement of proppant particles near the fracture inlet,the shorter the horizontal transport distance,and the more likely to accumulate near the fracture inlet to form a sand plugging in a short time.Fracture wall roughness could control the migration path of fracturing fluid to a certain degree and change the path of proppant filling in the fracture.On the one hand,the rough wall bulge raises the proppant transport path and the proppants flow out of the fracture,reducing the proppant sweep area.On the other hand,the sand-carrying fluid is prone to change flow direction near the contact point of bulge,thus expanding the proppant sweep area.

Pressure control method and device innovative design for deep oil in-situ exploration and coring

Deep oil exploration coring technology cannot accurately maintain the in-situ pressure and temperature of samples, which leads to a distortion of deep oil and gas resource reserve evaluations based on conventional cores and cannot guide the development of deep oil and gas resources on Earth. The fundamental reason is the lack of temperature and pressure control in in-situ coring environments. In this paper, a pressure control method of a coring device is studied. The theory and method of deep intelligent temperature-pressure coupling control are innovatively proposed, and a multifield coupling dynamic sealing model is established. The optimal cardinality three term PID (Proportional-Integral-Differential) intelligent control algorithm of pressure system is developed. The temperature-pressure characteristic of the gas-liquid two-phase cavity is analyzed, and the pressure intelligent control is carried out based on three term PID control algorithms. An in-situ condition-preserved coring (ICP-Coring) device is developed, and an intelligent control system for the temperature and pressure of the coring device is designed and verified by experiments. The results show that the temperature-pressure coupling control system can effectively realize stable sealing under temperature-pressure fields of 140 MPa and 150 °C. The temperature-pressure coupling control method can accurately realize a constant pressure inside the coring device. The maximum working pressure is 140 MPa, and the effective pressure compensation range is 20 MPa. The numerical simulation experiment of pressure system control algorithm is carried out, and the optimal cardinality and three term coefficients are obtained. The pressure steady-state error is less than 0.01%. The method of temperature-pressure coupling control has guiding significance for coring device research, and is also the basis for temperature-pressure decoupling control in ICP-Coring.

稠油热采井射孔孔眼应力分析及影响因素

针对稠油热采井生产过程中,射孔井段套管频繁出现损伤断裂的问题,基于弹塑性和热力学理论,采用有限元方法建立注汽—焖井—生产过程射孔套管有限元热力学耦合模型,对各阶段射孔套管应力分布特征进行研究,并开展不同射孔参数下射孔套管强度影响规律分析。研究表明:生产过程中射孔孔眼位置出现明显应力集中现象,在温差及内外压差等共同作用下,注采前期套管应力最大可达498.16 MPa,并逐渐产生塑性失效现象,当注采作业完成时,套管塑性失效现象最严重;随着射孔相位角增大,射孔密度对Mises应力值的影响逐渐减小,而套管孔眼最大应力与射孔相位角成反比关系。该研究对延长稠油热采井射孔套管使用年限和保障正常生产作业具有十分重要的意义。

Cade Oil Poisoning: A Case Series

Objectives and Study: Cade oil is aromatic oil obtained from the branches and wood of Juniperus oxycedrus, common in the Mediterranean region and widely used in traditional medicine. This oil contains many chemical compounds with neurological, cardiac, renal, respiratory, hepatic, and gastrointestinal toxicity. Cade oil poisoning often requires intensive care admission due to the severity of the clinical picture. The objective of this study is to highlight the multiple manifestations found in the pediatric population due to cade oil exposure objectifying its significant toxicity. Methods: The authors report during this article a series of five cases of cade oil poisoning on pediatric patients hospitalized in the pediatric intensive care unit of El HARROUCHI hospital at the CHU Ibn Rochd in Casablanca during the period from 11/01/2022 to 12/07/2022. The patients have been exposed, a few hours before their admission, to an external cade oil application used by parents for therapeutic purposes. Main Findings: Our patients were aged from 1 month to 4 years, the average age was 1.5 years with a female predominance and a sex ratio of 1.5:1. The patients had no prior medical history, and the cade oil application was spontaneously declared by the parents of only 2 patients, 3 of them reported the use of it after the detection of the substance by the clinician. For all the cases, cade oil was applied to treat fever. All five (5) patients presented initial neurological signs. 3 of them were admitted to an acute consciousness disorder and the 2 other patients presented respectively a convulsive status epilepticus and generalized-onset seizure. We report respiratory symptoms in 4 cases ranging from a simple caught, rhinorrhea to severe respiratory distress. Three patients presented acute liver failure with very high transaminase levels associated with acute kidney failure. Two of them presented digestive symptoms such as abundant hematemesis, vomiting, and watery diarrhea. All patients received high doses of N acetylcysteine in their initial treatments. The evolution was unfavorable for 4 patients who developed a multiorgan failure, 3 of them died, with a good clinical improvement in the fifth patient after supportive and symptomatic treatment. Conclusion: Cade oil poisoning remains a very frequent situation in our context. Its toxicity is widely described in the literature. The increasing number of cases admitted, and the seriousness of the clinical picture require mass awareness among the population and the scientific community toward the use of medicinal plants.

案例教学法在“油气层保护”课程中的应用

在新时代背景下,社会需要的是理论知识丰富、实践能力较强的复合型人才,若是沿用传统的教学模式,难以培养出符合社会需求的人才。案例教学法作为一种新型的互动教法,可有效弥补传统教学模式缺乏互动性、实践性的问题,促进复合型人才的培养。基于此,以油气层保护课程为主要研究对象,对其教学现状进行分析,并对案例教学法在该课程中的应用策略进行探讨,以其为相关专业教师提供参考。

基于破乳诱导萃取和ICP-MS/MS分析渣油中的微量金属元素

基于破乳诱导萃取提出利用电感耦合等离子体串联质谱(ICP-MS/MS)测定渣油中多种金属元素的新策略。渣油样品经二甲苯稀释降低黏度后采用质量分数6%的Triton X-114乳化,超声水浴破乳25 min,利用体积分数40%的盐酸萃取渣油中金属元素至水相,采用ICP-MS/MS测定其中10种金属元素Na、Mg、Al、Ca、V、Cr、Fe、Ni、Cu、Zn的含量。详细评估了破乳诱导萃取条件对渣油中金属元素萃取效率的影响,在串联质谱(MS/MS)模式下,利用氦碰撞气或不同反应气消除了金属元素的质谱干扰,采用标准参考物质NIST SRM 1634c(燃油中的微量元素)验证了方法的准确性,以微波消解技术处理渣油样品并采用扇形磁场电感耦合等离子体质谱(SF-ICP-MS)进行对比分析验证了方法的可靠性。结果显示,金属元素在各自的含量范围内呈现良好的线性关系(线性相关系数≥0.9997),检出限(LOD)为2.05~31.4 ng/L,NIST SRM 1634c的测定结果与标准参考物质提供的认证值及文献报道的参考值基本一致,置信度水平达到95%,ICP-MS/MS方法与SF-ICP-MS的对比分析结果无显著性差异。所建立的ICP-MS/MS方法操作简单,分析速率快,准确可靠性好,已用于渣油中多种金属元素的质量评价。

轧制方向对新型125KSI高钢级油套管性能的影响

利用室温拉伸试验、冲击试验、断裂韧性试验检验了超深井用新型125KSI高钢级油套管中沿扎向和垂直于扎向的强度、塑性、冲击韧性和断裂韧性。通过OM、SEM和EDS技术,对显微组织、晶粒长宽比和夹杂物分布进行了分析,讨论了显微组织对油套管各种性能的影响。结果表明,油套管材的微观组织由板条状回火马氏体和均匀弥散分布的细小Al_(2)O_(3)-MnS类混合夹杂物组成,晶粒为8.5级。轧制后,沿管道轧制方向的晶粒长宽比增加,导致强度增加,塑性降低且平行于管道轧向的冲击韧性下降;沿管道轧制方向的夹杂物分布更加集中,导致临界距离变小,裂纹扩展方向垂直于轧制方向的断裂韧性降低。

螺杆泵转速对油水旋流分离管流场特性的影响

旋流分离器在井下采油螺杆泵作用下会发生复杂的振动现象,对旋流分离器内部流场造成一定影响。为研究螺杆泵不同转速下旋流分离器内部流场的变化规律,以同井注采工艺中螺杆泵作用下的旋流分离管柱为研究对象,针对振动壁面旋流分离管柱结构及工作特点,基于计算流体动力学方法、计算固体力学方法以及流固耦合理论,建立流固耦合力学模型;利用流固耦合分析方法,对双螺杆泵转动条件下井下旋流分离管柱内速度场、油相分布、涡量及湍动能等流场特性进行分析。分析结果表明:随着螺杆泵转速升高,分离器内切向速度和轴向速度强度逐渐减弱,径向速度的不对称性逐渐加剧,转速的周期性变化还会造成径向速度场分布的偏移;螺杆泵不同转速下旋流分离器内部涡量分布不同,随着转速升高,溢流管以及锥段部分附近相关流场的涡旋明显增强;旋流器溢流口附近油相体积分数会随着螺杆泵转速的升高而减小;不同螺杆泵转动状态下,大颗粒油滴的分布不同。所得结果可为螺杆泵井下旋流分离同井注采系统的设计及螺杆泵的转速设定提供参考。

基于YOLOv5的油气井套管接箍检测方法

针对目前在可视化测井领域,利用人工对测井视频中的接箍进行识别校深时存在的检测效率低下、检测误差高的问题,提出一种基于YOLOv5算法的接箍智能检测方法。首先对井下的接箍图像进行采集,在缺乏公开数据集的情况下,通过数据增强的方法制作接箍数据集,再对增强后的数据集使用labelimg工具进行数据标注,然后将标注好的数据集送入YOLOv5网络中进行训练,最后使用训练好的最佳权重进行接箍识别并计数。测试结果表明,该方法能实现对当前测井视频中接箍的准确识别,接箍计数的正确率为100%,并且检测效率高,平均每帧检测时间为15 ms。

碳酸盐岩缝洞型油藏流固耦合下的油水两相流动特征

为提高缝洞型碳酸盐岩油藏采收率,探究其流固耦合下的油水两相流动特性,根据不同介质中的流体流动规律,建立了Stokes-Darcy两相流体流动模型;基于有效应力原理和广义胡克定律,建立了适用于缝洞型碳酸盐岩油藏的油水两相Stokes-Darcy流固耦合数学模型;分别针对有无流固耦合的缝洞型碳酸盐岩油藏,进行了宏观和细观的油水两相流体流动模拟。研究结果表明:油藏有无流固耦合作用,其油水两相流体流动特性在基质区差异较大,在溶洞内差异较小,注水速度对缝洞型碳酸盐岩油藏的油水流动影响较大。

基于机-电-磁-流整体耦合的油阻尼断路器保护特性的容差设计

油阻尼断路器的主要特点是在电路发生短路、过载等情况时能够自动脱扣,断开电路,从而保护人员和设备的安全,常用于变电站等场所。文章在以往对油阻尼断路器油阻尼力、电磁铁静态特性、操作机构性能等研究的基础上,构建一个基于机-电-磁-流多体多自由度多场耦合的一体化虚拟样机整体耦合模型;接着对该整体耦合模型的保护特性进行了仿真与分析,通过仿真得到了不同电流倍数下动触头的分断特性,并通过实验验证了整体耦合模型和仿真结果的正确性;最后,为减小产品保护特性的分散程度,提高油阻尼断路器的稳定性,文中结合稳健容差设计技术,选取不同电流倍数下触头的断开时间作为目标函数,以极靴半径、细铁芯半径、粗铁芯半径、粗铁芯高度作为关键设计参数,通过正交试验和贡献率分析法对目标函数进行容差分配,使得触头断开时间的分散度比原来减少39.165%。研究成果将会对电器产品的研发提供理论指导。

航空发动机用滑油泵组碟簧压紧有限元分析

为保证滑油泵组关键部件配流盘与偏心泵体的稳定压紧及泵盖的安全性,依据GB/T 1972—2005标准,选用2只单片碟簧以精准对合方式安装于滑油泵组上.在考虑潜在温度场热变形的影响下,采用热固耦合方法,基于Workbench平台对滑油泵组在不同碟簧初始压缩量(0.6,0.7,0.8,0.9 mm)下进行有限元分析.研究结果表明:当初始压缩量小于0.7 mm时,滑油泵的主要部件受到的压紧力较小,主要受油液周向推力的影响;随着初始压缩量从0.7 mm增至0.9 mm,预压缩端的变形量呈现相应的增长趋势,同时滑油泵体挡板所承受的轴向力也随着初始压缩量的递增而呈现线性增长的规律;在此过程中,配流盘与偏心泵体所受到的轴向推力随着初始压缩量的增大而逐渐增大,确保其能够有效地被压紧且泵盖保持完好无损.研究结果不仅为滑油泵组的初始安装提供了理论依据,而且有助于指导实际工程应用中的安装操作,从而确保滑油泵组的正常运行与使用寿命.

5Cr油套管钢在含Cl^(-)的CO_(2)环境中的腐蚀特性研究

目的掌握油气井生产中CO_(2)腐蚀对油套管的影响规律,研究兼顾耐蚀性和经济性的5Cr油套管材料在含Cl^(-)的CO_(2)环境中不同时间下的腐蚀演变规律。方法采用XRD、XPS、SEM和EDS等技术分析5Cr油套管钢在不同时间下腐蚀产物膜的演变情况,利用丝束电极(WBE)和阻抗测试(EIS)技术对其腐蚀电化学行为进行研究。结果5Cr油套管钢腐蚀后期的平均腐蚀速率约为初期的1/2,在腐蚀14 d后,腐蚀产物膜中的Cr富集大于30%,Cr、Fe质量比达到较高水平,约为基体的15倍。随着腐蚀的进行,电荷传递电阻和产物膜覆盖引起的电阻增大,电化学反应阻力增大。在腐蚀前期具有局部不均匀性,随着腐蚀的进行,电极腐蚀电位有负移现象,最终分布区间为−0.59~−0.61 V,电极表面阳极电流区域大幅减少。结论在腐蚀时间延长的条件下,5Cr油套管钢腐蚀产物膜的致密性增加,电荷传递电阻呈变大趋势。在产物膜下的5Cr油套管钢区域,电流发生由阴极向阳极极性转变的现象,产物膜存在的孔隙使5Cr油套管钢基体金属被腐蚀,从而导致阳极电流的出现。表面局部腐蚀电位阳极区的形成和扩展使其有产生点蚀的倾向,但腐蚀产物逐渐沉积在点蚀坑内壁,形成了Cr富集的保护性表面层,原发生点蚀区域由原阳极活性点位转变为阴极区,对其发展起到了抑制作用。