Review of research on intelligent diagnosis of oil transfer pump malfunction

Oil transfer pump is the key dynamic equipment in the process of oil and gas gathering and transportation,and its working reliability directly affects the safety of oil and gas storage and transportation.Intelligent diagnosis is a key technical method to reduce failure rate of oil transfer pump,ensure the safety of gathering and transportation process,and avoid major safety accidents caused by oil transfer pump failure.Various oil transfer pumps have been emerged in recent decades,and the common fault types and characteristics of oil transfer pump have been brought out in the review.This article highlights on the research of the fault signal and processing methods of oil transfer pump.Firstly,the fault signal of the oil transfer pump is discussed and the advantages and disadvantages of different signal extraction are analyzed.Secondly,the intelligent diagnosis method of oil transfer pump and the shortcomings of the existing methods are pointed out.Finally,the conclusions are given and the future development perspectives of oil transfer pumps are suggested.The main contribution of this review is to give a syn-thetic understanding on oil transfer pumps.

Optimal Operation for Baoying Pumping Station in East Route Project of South-to-North Water Transfer

Baoying pumping station is a part of source pumping stations in East Route Project of South-to-North Water Transfer in China. Aiming at the characteristics of head varying, and making use of the function of pump adjustable blade, mathematical models of pumping station optimal operation are established and solved with genetic algorithm. For different total pumping discharge and total pumping volume of water per day, in order to minimize pumping station operation cost, the number and operation duties of running pump units are respectively determined at different periods of time in a day. The results indicate that the saving of electrical cost is significantly effected by the schemes of adjusting blade angles and time-varying electrical price when pumping certain water volume of water per day, and compared with conventional operation schemes （namely, the schemes of pumping station operation at design blade angles based on certain pumping discharge）, the electrical cost is saved by 4.73%-31.27%. Also, compared with the electrical cost of conventional operation schemes, the electrical cost is saved by 2.03%-5.79% by the schemes of adjusting blade angles when pumping certain discharge.

Research on single hole heat transfer power of ground source heat pump system

In this paper,the single hole heat transfer power of the ground source heat pump system in Hengshui is compared with data gained from thermal response test.The results show that maximum monitoring data of heat transfer power per meter in summer is 97.1% of the test data,and the average value accounts for 81.8%.The per meter heat power data through on-site thermal response test can provide references for designing engineering project and optimizing ground source heat pump system as these data do not vary greatly from the actual monitoring data.

Numerical Studies of Convective Mass Transfer Enhancement in a Membrane Channel by Rectangular Winglets

Numerical calculations were conducted to simulate the flow and mass transfer in narrow membrane channels with and without flow disturbers. The channel consists of an impermeable solid wall and a membrane surface with a spacing of 2.0 mm. The flow disturbers studied include rectangular winglets, which are often used as longitudinal vortex generators to enhance heat transfer in heat exchanger applications, as well as square prism, triangular prism, and circular cylinder, which are used here to mimic the traditional spacer filaments for comparison of their abilities in enhancing the convective mass transfer near the membrane surface to alleviate the concentration polarization. The disturber performance was evaluated in terms of concentration polarization factor versus consumed pumping power, with a larger factor meaning a more serious concentration polarization.Calculations were carried out for Na Cl solution flow with Reynolds numbers ranging from 400 to 1000. The results show that the traditional flow disturbers can considerably reduce the concentration polarization but cause a substantial pressure drop, while the rectangular winglets can effectively reduce the concentration polarization with a much less pressure drop penalty. The rectangular winglets were optimized in geometry under equal pumping power condition.

Investigation of the hydrodynamics of slug flow in airlift pumps

A slug flow model considering the dispersed bubbles entrained from the tail of Taylor bubble(TB) and recoalesced with the successive TB was proposed. Experiment was conducted to test the validity of this model by using a high-speed camcorder and particle image velocimetry(PIV). It was found that the model was valid for predicting the characteristics of slug flow in airlift pump within average error of 14%. Moreover, large pipe diameter was found to accelerate the rise velocity of TB and decreases void fraction in liquid slug by a small margin.

降速方式对混流泵压力脉动特性的影响

混流泵在降速过程中的内部流动特性变化对其性能和稳定性有重要影响。针对这一问题,该研究探究了混流泵在降速过程中内部流动的复杂性,尤其关注不同降速方式对泵内压力脉动特性的影响。通过构建多通道测试系统,收集了混流泵在不同降速方式下的外特性参数信号和泵内压力脉动信号。并采用非稳态信号处理技术,从时域、频域和时频三方面探究不同降速方式对叶轮出口和导叶内部的压力脉动特性的影响以及二者之间的相关性。结果表明,泵内压力脉动的峰值和样本熵的变化趋势与不同降速方式的幂指数呈正相关关系;在整个降速过程中叶轮出口压力脉动对导叶内压力脉动起主导作用;叶轮出口和导叶内部压力脉动之间的相干频率主要集中于80~120 Hz之间;在不同降速过程中叶轮出口和导叶内部的压力脉动之间强相关区域的频带范围保持不变,但是强相关区域在整个降速过程频带范围中的占比有所变化;对于具有固定初始转速和目标转速的降速过程,降速方式的改变不会影响叶轮出口和导叶内压力脉动的相干频率。研究结论可为揭示混流泵瞬态运行特性及提高混流泵降速运行中的稳定性提供参考。

补气增焓准二级压缩空气源热泵理论最佳除霜量研究

为解决能源浪费的问题,通过引入相关结霜模型进行理论分析,结合实验数据得出“理论最佳除霜量”的半经验公式。为验证该公式有效性,针对某厂家的补气增焓准二级压缩空气源热泵进行不同工况下:空气相对湿度65%、70%、80%,对应的空气干球温度-4~4℃的温度区间的实验测试。通过测试不同状态下的实际除霜量与“理论最佳除霜量”的半经验公式计算的理论除霜量进行比较,发现两者相对误差较小,保持在±10%以内,该公式对霜层后期的预测值较为准确,可作为设计补气增焓准二级压缩能够空气源热泵融霜时间控制的基准。

基于NSGA-Ⅲ算法的长距离调水泵站多目标优化调度研究

针对长距离调水泵站运行过程中水泵运行效率低、安全隐患较大等问题,以调水泵站运行电费最小、水泵平均效率最大、水泵流量平均偏离度最小、水泵平均启停频次最小为目标建立优化模型。以华东某沿海城市调水工程为例,采用第三代非支配排序遗传算法(NSGA-Ⅲ)求解优化模型,运用层次分析法与CRITIC法进行组合赋权,结合逼近理想解排序法(TOPSIS)进行方案优选。结果表明,相较于常规调度方案,优化调度方案中两泵站的运行电费和水泵流量平均偏离度均显著降低,水泵平均效率均显著提高,水泵平均启停频次均有所减少。表明在综合考虑泵站运行经济性的情况下,所建优化模型能够有效降低安全隐患。

基于传递矩阵理论的隔膜泵振动噪声预测方法研究

隔膜泵是家用净水器的动力装置,其振动噪声会对用户的使用体验产生负面影响。构建有效的隔膜泵振动噪声预测方法,可以在泵的设计阶段实现噪声的准确预测,从而降低设计成本。根据水泵的工作原理,该文针对一种隔膜泵的轴系,构建了基于传递矩阵理论的横向振动动力学模型,建立了轴系固有频率的计算方法。引入扩展传递矩阵,建立水泵外激励等效模型,发展了典型工况下轴系对水泵外壳作用力的频响分析方法。将作用力作为输入,利用有限元软件计算泵壳的辐射声场。开展泵体辐射噪声的试验测试,结果显示泵体的平均声压级与仿真结果具有较好的一致性,说明了该文提出的等效建模方法的准确性,对隔膜泵的低噪声优化设计与分析具有指导意义。

基于土壤分层当量物性的地埋管换热器换热模型研究

文章综合考虑了土壤分层与地下水渗流等情况,结合实测数据,通过地埋管外壁温度计算得出地埋管内部流体温度与不同分层土壤的热物性参数,根据土壤当量物性进行分层,据此建立地埋管换热模型。经过对比验证实验发现,分层换热模型比常规均质模型更接近实测值,误差更小;基于土壤分层当量物性的地埋管换热器换热模型模拟出水温度与实测值平均绝对误差为0.21℃,模拟进、出口换热温差与实测值平均绝对误差为0.14℃,具有较高的准确度,可为工程设计提供依据并作为后续地埋管换热优化研究的基础。

某温泉庄园热源方案技术对比分析

随着热泵技术的快速发展和煤改电政策的推进,空气源热泵的应用优势越来越凸显。以大连某温泉庄园热源设计为例,结合业主意愿和要求,提出三种热源方案:温泉水经板换换热的直供方案;温泉水板换换热和水源热泵联合供暖;采用空气源热泵供暖。对三种设计方案进行了技术经济对比分析,提出空气源热泵供暖方案是最经济的。在保证电力可靠,安全运行的同时,合理利用能源,提高了经济效益。

输油泵故障智能诊断研究综述

油气管道的运行离不开输油泵,输油泵故障智能诊断是保障输油系统正常运转、防止输油系统失效引起重大事故的关键。回顾了输油泵常见故障和故障信号,研究了输油泵的故障诊断依据和信号处理方法,归纳了智能诊断方法和2种故障维护方法,讨论了输油泵故障类型,分析了不同信号判断依据提取方法的优缺点,提出了输油泵智能诊断方法存在的问题,展望了输油泵发展方向,总结了输油泵故障智能诊断方法。

基于BP算法的中深层同轴套管换热量预测

通过搭建热泵测试试验台,进行多工况试验获取试验数据来建立BP神经网络同轴套管换热量预测模型,并进行仿真模拟,对同轴套管换热量进行预测。结果表明:(1)热泵系统在水流量28 m^(3)/h、回水温度10℃的工况下稳定运行能效最高,同轴套管有效换热量为563 kW。(2)隐含层节点数为12时,BP神经网络预测模型最优,训练最大均方误差MSE为0.023%,最优模型基本结构为9-12-1。(3)对比同轴套管换热量预测值与检验值仿真结果,BP神经网络同轴套管换热量预测平均百分比误差MAPE为0.235%,预测准确率为99.765%。该预测模型具有较高的精度和可靠性,能够准确预测同轴套管换热量的变化趋势,对于提高热泵系统的能效和性能具有广泛的应用价值。

微通道型气泡泵驱动两相流传热特性

基于沸腾现象的浸没式液冷技术适用于芯片(服务器、数据中心等)以及电机冷却等,可实现冷却系统的模块化、集成化和小型化,具有广阔的应用前景。在浸没式液冷系统的开发中,通常希望在不影响系统性能的前提下,尽量减少冷却工质的充填量。提出气泡泵技术,降低冷却系统中液体工质充填量,同时利用沸腾气泡驱动的气液两相上升流作为动力,驱动工质循环冷却整个系统。选取Novec-7100为工质,建立可视化实验系统,针对气泡泵驱动的气液两相流动特性、气液输运性能以及传热性能展开研究。结果表明,所构建的3 mm×3 mm微通道型气泡泵冷却系统,在120 mm的冷却液浸没高度下实现了所选取参数范围内的最佳性能,可在0.89~9.68W/m^(2)的热通量范围内实现两相流循环输运。

制热工况下跨临界CO_(2)热泵最优排气压力的影响因素研究

最优排气压力是影响跨临界CO_(2)热泵性能最重要的因素。为研究最优排气压力存在原因及其影响参数,并揭示各参数对最优排气压力的影响机理,基于传热夹点理论对最优排气压力进行了理论分析。利用AMESim软件搭建了考虑气体冷却器内部传热夹点的跨临界CO_(2)热泵模型进行仿真计算,在进水温度为10~40℃、出水温度为60~90℃、环境温度为-30~25℃的宽工况内定量研究了进水温度、出水温度、环境温度及回热率对热泵系统最优排气压力的影响。研究结果表明:进水温度越低、出水温度越低、环境温度越低,均会导致传热夹点向气体冷却器出口移动,从而使系统的最优排气压力减小;同时,采用回热方式也能够将传热夹点进一步向气体冷却器出口推移,从而减小最优排气压力。研究结果证实传热夹点的位置对于系统最优排气压力的取值具有重要影响,因此基于传热夹点的分析与设计方法具有更强的适用性,可为热泵供暖、车辆热管理等用途中CO_(2)热泵系统的设计和性能优化提供理论与工程基础。

传输用蠕动泵管路失效分析与应用工艺优化

化工生产中传输液体用的蠕动泵管路,常见失效故障有软管破损、停机回流、流量降低。通过对传输管失效状态的分类、不同失效状态的原因分析,得出传输压力、软管壁厚、软管材质对软管磨损的影响,提出通过调整蠕动泵压力、软管安装长度和更换软管材质来提升不同工艺要求下的蠕动泵传输可靠性。

圆形隧道衬砌内毛细管换热器间歇运行的传热性能

隧道地源热泵是解决地铁隧道热污染的有效技术之一,毛细管换热器(CHE)因具有抗腐蚀、易弯曲、换热性能好、节省空间等优点被广泛应用于隧道地源热泵系统的前端换热器。基于示范工程建立了CHE流-热耦合传热模型,并在TRNSYS平台搭建CHE仿真系统,对隧道衬砌内CHE在连续、间歇运行下的传热性能进行分析。结果显示,当运行时间比由1/3逐渐增至1时,制冷季和采暖季第7日的CHE日均热流密度分别由100.59、87.42 W/m^(2)降至78.14、68.62 W/m^(2),相应的围岩内表面温度分别随之增大和减小,表明间歇运行能显著提高换热器的传热性能,并有助于缓解隧道围岩冷热堆积问题。

热泵引射对烟草烘丝机系统的影响规律研究

通过在烟草烘丝机蒸汽系统中并入热泵引射系统,并以热泵引射系统为基础负荷,原有系统作为调节负荷,对比并入前后各参数的变化规律。结果表明,并入热泵引射系统后,烘丝系统获得了整体性优化。烘丝机滚筒壁温有一定提升,温度均匀性也有改善,筒体内疏水不畅的问题彻底解决,烟丝出口含水率的均匀性得到提高,根据运行疏水压力可知蒸汽引射在该系统上的理论节能率可达0.3%~3.35%,但实际节能效果还需运行参数的匹配调节才能实现。

流固耦合作用下泵站大体积混凝土结构振动特性分析

在泵站运行过程中,由转轮和导叶之间水体的动静干扰所引起的压力脉动是引起泵站混凝土结构及机组振动的主要原因。现有关于泵站及水电站厂房的研究中,仅以数值参数形式表达脉动,并未真实反映流体与导叶间的相互水力干涉。采用有限元软件ADINA建立泵站混凝土结构、流道和流体的耦合三维模型,特别将机架、轴流泵等金属结构建入模型中,真实反映流体与固定导叶间的相互水力干涉,模拟脉动传递路径。分析了泵站大体积混凝土结构的振动特性,并对泵站运行安全性作出评价分析。研究结果可为工程实践提供参考。

空气源热泵冷凝器和蒸发器能力提升的研究

为了提升空气源热泵的换热能力,针对影响热泵能力的因素进行了讨论研究。在保证设计工况一定的条件下,以热泵系统的冷凝器和蒸发器为研究对象,对其结构、材料、传热特性以及冷热流体的流动方式进行了分析研究,以保证冷凝器和蒸发器能力最优。对微通道的摆放角度、形状和不同种类制冷剂进行了详细的研究。最后,在保证系统工况稳定的条件下,通过正交试验对热泵系统进行全面调试,给出了最优的参数组合。