Numerical analysis of pulsating heat pipe based on separated flow model

The examination on the operating mechanism of a pulsating heat pipe (PHP) using visualization revealed that the working fluid in the PHP oscillated to the axial direction by the contraction and expansion of vapor plugs. This contraction and expansion is due to the formation and extinction of bubbles in the evaporating and condensing section, respectively. In this paper, a theoretical model of PHP was presented. The theoretical model was based on the separated flow model with two liquid slugs and three vapor plugs. The results show that the diameter, surface tension and charge ratio of working fluid have significant effects on the performance of the PHP. The following conclusions were obtained. The periodic oscillations of liquid slugs and vapor plugs were obtained under specified parameters. When the hydraulic diameter of the PHP was increased to d=3mm, the frequency of oscillation decreased. By increasing the charging ratio from 40 to 60 by volume ratio, the pressure difference between the evaporating section and condensing section increased, the amplitude of oscillation reduced, and the oscillation frequency decreased. The working fluid with higher surface tension resulted in an increase in the amplitude and frequency of oscillation. Also the average temperature of vapor plugs decreased.     

火电厂管道清灰装置的液压系统的设计

针对化学清洗的成本高、污染大和物理清洗的除垢率低的特点,为解决火电厂输灰管道除垢问题提出了一种新式的机械清洗方法,该方法可实现灰垢的在线清洗,降低灰垢清洗的成本,延长管道的使用寿命,清洁无污染,并且可以达到满意的除垢率。本文主要介绍了机械清洗液压部分的工作原理,并对液压部分的设计计算及零件的选取做了详细的叙述。     

输气站场管道的外腐蚀检测技术

为了确保输气站场管道安全稳定运行,防止站场管道发生腐蚀穿孔,需要对站场管道进行外腐蚀检测,知道站场管道状态做出安全评估。采用PCM检测方法检测管道防腐涂层损坏程度就可间接得到管道的腐蚀情况,从而实现埋地管线的不开挖检测。提出一些检测时需改进的意见。检测之前,要了解清楚站场管道的走向和埋深状况,以及各处配件状况,从而确定检测的管段和信号接入点位置;检测过程中,应尽量关闭埋地电源线的电源;检测完毕之后要对管道防腐涂层破损处进行定位,对于电磁信号波动比较大的地方,应多次测量,排除干扰因素,还可以开挖检测。所以,通过PCM检测防腐涂层来判断站场管道的外腐蚀情况是经济可行的方法。     

A regression model for prediction of pipe conveyor belt contact forces on idler rolls

The paper presents design and verification of regression models for prediction of pipe conveyor belt contact forces on idler rolls. Their advantage is in the fact that they have been created according to the real experimental measurement. The obtained models correspond with real operational conditions. The concept of the experimental rig at the Technical University of Košice is designed so that it represents 8 m long section of pipe conveyor. The conveyor belt is an object with action of tension force and at the same time it takes the initiative in the contact force formation. Several criteria have been used to verify the presented regression models. The tensioning force 9000, 12,000 and 15,000 N have MPE of prediction error less than 5%. About 120,000 measured values have been processed during the evaluations which correspond to approximately 15,000 results from experimental measurements.     

管道无损检测与评价技术

为适应国内石油化工企业大量管道检测维护的急需，介绍了国际上有关管道在线无损检测、运行监视及泄漏检测的新技术、新设备和其应用情况与发展动态     

简谈超高压管道系统的设计及安装

我国目前尚无超高压管道的设计标准及规范,文章根据我公司实际承担的两套高压聚乙烯装置的实际设计及现场施工经验,结合BASELL超高压设计标准,针对设计压力大于等于32．5MPa的超高压管道系统的使用标准、连接方式、储存和运输、现场安装,以及超高压管道支架安装等的特殊要求进行了简要介绍。     

四川盆地老气田二次开发优化技术及应用

经过近60年的开发,四川盆地的许多老气田已进入低压、低产的开发中后期,部分气田虽然已濒临废弃,但其中仍尚存较多剩余天然气资源未采出。通过梳理分析,认为具备二次开发条件的气田多存在地层水活跃形成水封难以解封、低渗透储量难动用等问题。为此,从老气田二次开发的定义出发,全面阐述了其技术路线及优选条件:(1)在建立缝洞系统多储渗体模式的基础上,采用压力重整曲线进行地质模型正演、生产动态反演特征曲线诊断,提出了复杂岩溶缝洞系统多储渗体识别及定量描述方法,结合U型管气水赋存新模式,形成了强水侵多缝洞系统天然气储量计算新技术;(2)建立孔、洞、缝三重介质数值模型,形成强水侵底水缝洞气藏"水平井排水+直井采气"排采井网模拟及效果评价新技术;(3)依托精细气藏描述形成的配套集成技术,重构气藏地质模型,分类评价气藏低渗透储量,结合井网优化、水平井地质导向、分段酸化压裂等工艺技术,进一步提高有效动用率;(4)建立多节点、多环节输气管网模型,形成区域性管网整体模拟优化及预测技术。实施效果表明,该二次开发技术在老气田产能建设、提高老气田采收率、延缓老气田产量递减、稳定老气田产量等方面均具有明显成效。     

青西凹陷窟窿山构造青2-50井钻井液技术

青2-50井地层十分复杂,如泥页岩易发生水化坍塌,硬脆性页岩易垮,层理裂缝发育,易漏,地层倾角大,井眼应力不均衡等,因此为保证井壁稳定,需把钻井液配方的优选和适时有效地转化作为钻井施工的重点.在柳沟庄组以上地层,采用了加生石灰的阳离子钻井液,通过保持较高矿化度,满足了地层和工程的需要.在钻至深部地层以后,转化为阳离子聚磺钻井液,提高了原体系的抗温能力,并解决了深井阶段的裂隙封堵、地层垮塌、润滑防卡和油层保护等难题.青2-50井的顺利完钻为提高该区块的钻探开发速度积累了经验,并建议选用复合金属离子(或两性离子)聚合物(防塌)钻井液替代阳离子钻井液.     

滩海敷管船用张紧器

管线张紧器是敷管船的关键配套设备,为了加快我国滩海油田的开发,我们研制成功了滩海敷管船用张紧器, １９９８年进行了现场试验,并于 １９９９年 ３月通过中国石油天然气集团公司组织的、以中国工程院院士顾心怿为首的专家鉴定。     

丙烷塔空冷器集合管管道阻尼减振技术研究

针对济南某炼油厂丙烷塔空冷器集合管管道振动问题,通过现场测量管道系统的振幅和频率,运用有限元分析软件对管系进行模态分析,并与实测数据进行对比,提出了管系振动的解决方案。在不停机的情况下,在管道的适当位置安装阻尼器,有效降低了管道系统的振幅,提高了管道的运行寿命。