煤层气田采气管网管材优化研究与应用

由于煤层气田的建设环境相对复杂,多处于山地丘陵地带,对采气管道的防腐蚀性、稳定性、柔韧性及现场适应性要求较高。随着聚乙烯(PE)100管材制造技术的不断成熟,其优良的性能更加适用于山区煤层气田低压采气管网。通过对煤层气管材的优选,PE100 SDR17.6(薄壁)系列管材符合煤层气现场使用条件,能够满足煤层气田高效、低成本开发的要求,并且,经生产实践验证,其安全可靠性较高。因此,建议在同类煤层气田地面管网建设中推广应用。

陕西蒲城电厂二期二程“四大管道”管材优化

该文介绍了陕西蒲城电厂二期工程四大管道材质选择，只有再热冷段沿用了九五管材推荐的A106B和A672B70CI532，主蒸汽同是在比较了P22，P91，X20CrMoV121（F12）各方面因素，选择了P91作为高温高压管道材质，高压给水择优选用了15NiCuMoNb5.

海上S油田聚合物驱注入工艺问题分析及应对策略

针对海上S油田聚合物驱区块逐渐出现的注入压力高、部分井欠注、注聚区块含水上升快、油井产液量下降等问题,以地面注聚工艺流程为研究对象,分析了管线腐蚀、结垢以及流程中聚合物堵塞的主要原因。结果表明,海上S油田不同水源注入水Cl^-含量较高,形成易腐蚀的极性环境,造成流程管线腐蚀严重;管线中垢样成分以Fe3O4、钙镁垢为主,堵塞注聚管汇,注入能耗增加,影响工作液流速;流程中黄褐色条状堵塞物为聚合物与铁离子及其他金属阳离子相互作用形成。在注聚流程管线更换时,可以采用超低碳高铬钢和低碳高铬钢,以降低管线腐蚀速率,提高钢的腐蚀性能;注聚流程中应在熟化罐前加入稳定剂处理水中的铁离子,有效发挥铁离子稳定剂的作用。高效破胶氧化解聚剂对现场流程堵塞物具有明显的降解效果,降解率达100%。

地下污水管道防渗设计方案探讨

根据近两年来国家环保局对地下水资源污染防控要求,新建石油化工项目可能产生渗、泄漏污染的地下管道均需做防渗措施,简单介绍了工程中选择管道敷设方式、管道选材、选择不同结构等防渗设计方案,并提出进一步优化的防渗设计方案,为今后防渗设计提供参考和选择。

Sequential multi-objective optimization of thin-walled aluminum alloy tube bending under various uncertainties

Combining the design of experiments(DOE)and three-dimensional finite element(3D-FE)method,a sequential multiobjectiveoptimization of larger diameter thin-walled(LDTW)Al-alloy tube bending under uncertainties was proposed andimplemented based on the deterministic design results.Via the fractional factorial design,the significant noise factors are obtained,viz,variations of tube properties,fluctuations of tube geometries and friction.Using the virtual Taguchi’s DOE of inner and outerarrays,considering three major defects,the robust optimization of LDTW Al-alloy tube bending is achieved and validated.For thebending tools,the robust design of mandrel diameter was conducted under the fluctuations of tube properties,friction and tubegeometry.For the processing parameters,considering the variations of friction,material properties and manufacture deviation ofmandrel,the robust design of mandrel extension length and boosting ratio is realized.

Optimal design of functionally graded Pm PV/CNT nanocomposite cylindrical tube for purpose of torque transmission

Carbon nanotube(CNT)/polymer nanocomposites have vast application in industry because of their light mass and high strength. In this work, a cylindrical tube which is made up of functionally graded(FG) PmP V/CNT nanocomposite, is optimally designed for the purpose of torque transmission. The main confining parameters of a rotating shaft in torque transmission process are mass of the shaft, critical speed of rotation and critical buckling torque. It is required to solve a multi-objective optimization problem(MOP) to consider these three targets simultaneously in the process of design. The three-objective optimization problem for this case is defined and solved using a hybrid method of FEM and modified non-dominated sorting genetic algorithm(NSGA-II), by coupling two softwares, MATLAB and ABAQUS. Optimization process provides a set of non-dominated optimal design vectors. Then, two methods, nearest to ideal point(NIP) and technique for ordering preferences by similarity to ideal solution(TOPSIS), are employed to choose trade-off optimum design vectors. Optimum parameters that are obtained from this work are compared with the results of previous studies for similar cylindrical tubes made from composite or a hybrid of aluminum and composite that more than 20% improvement is observed in all of the objective functions.

Thermal analysis of a solar parabolic trough receiver tube with porous insert optimized by coupling genetic algorithm and CFD

In this paper, the heat transfer enhancement in a solar parabolic trough receiver tube with porous insert and non-uniform heat flux condition was investigated. A new optimization method, which couples genetic algorithm(GA) and computational fluid dynamics(CFD) based on Socket communication, was proposed to optimize the configuration of porous insert. After the acquisition of the optimal porous inserts, some performance evaluation criterions such as synergy angle, entransy dissipation and exergy loss were introduced to discuss the heat transfer performance of the enhanced receiver tubes(ERTs) with optimal and referenced porous inserts. The results showed that, for a large range of properties of porous insert(including porosity and thermal conductivity) and Reynolds number, the heat-transfer performance of ERT with porous insert optimized by GA is always higher than that of the referenced ERTs. Better heat-transfer performance can further improve the solar-to-thermal energy conversion efficiency and mechanical property of the solar parabolic trough receiver. When some porous materials with high thermal conductivity are adopted, ERT can simultaneously obtain perfect thermal and thermo-hydraulic performance by using the same optimized porous insert, which cannot be achieved by using the referenced porous insert. In the view of those introduced evaluation criterions, using the optimized porous insert can obtain better synergy performance and lesser irreversibility of heat transfer than using the referenced porous insert. Entransy dissipation per unit energy transferred and exergy loss rate have equivalent effects on the evaluation of irreversibility of heat transfer process. These evaluation criterions can be used as optimization goals for enhancing the comprehensive performance of the solar parabolic trough receiver.