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Experimental research on the contact force of the bi-directional pig in oil and gas pipeline

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Petroleum Science 2023年第1期20卷 474-481页

作者： Xiao-Xiao Zhu Chun-ming fu Yu-Tao Wang Shi-ming Zhang College of Mechanical and Transportation Engineering China University of Petroleum-BeijingChangpingBeijing102249China

The migration process of the pig in oil and gas pipeline is a complex dynamic *** the pigging operation,the variation of friction force caused by the nonlinear contact between the sealing disc and the pipe wall is the key factor affecting the dynamic characteristics of the pig *** present,the existed pigging models for predicting pigging behavior regard friction as an invariant *** research indicates that the friction force of the pig varies with the contact force and the lubrication ***,the assumption that the friction force is constant cannot reflect the friction dynamic characteristics of the pig during pigging,and will also affect the accuracy of the pigging *** the variation of friction force of pig under different conditions is the basis of establishing the transient dynamic model of a *** a result,in this paper,a method of direct measurement of contact force between the pig and the pipeline is presented,the contact force,the friction force,as well as the friction coefficient of the pig are obtained from the *** results in this paper can help to establish a more accurate dynamic model of pig.

关键词： Pipeline pig Sealing disc Contact force Friction coefficient Experimental rig

Thermodynamic analysis of the compositional control of inclusions in cutting-wire steel

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International Journal of Minerals,Metallurgy and Materials 2014年第7期21卷 647-653页

Data from a thermodynamic database and the calculation software FactSage were used to investigate the phase diagrams of the MnO？CaO？SiO2？Al2O3 system in cutting-wire steel and the effects of oxide components on the low-melting-point （LMP） zone in the cor-responding phase diagrams. furthermore, the activities of oxide components in the quaternary system at an Al2O3 content of 25wt%were calculated. The contents of dissolved [Al] and [O] in liquid steel in equilibrium with LMP inclusions in the MnO-CaO-SiO2-Al2O3 system were optimized. The results show that the MnO-CaO-SiO2-Al2O3 system possesses the largest LMP zone （below 1400℃） at an Al2O3 content of 25wt%and that the CaO content should be simultaneously controlled in the range of 40wt%to 45wt%. The activities of the oxide components CaO, MnO, and SiO2 should be restricted in the ranges of 0 to 0.05, 0.01 to 0.6, and 0.001 to 0.8, respectively. To obtain LMP inclusions, the [Al] and [O] contents in cutting-wire steel must be controlled within the ranges of 0.5 ×10^-6 to 1.0 ×10^-5 and 3.0 ×10^-6 to 5.0 × 10^-5, respectively.

关键词： wire steel curing inclusions thermodynamic calculations activity oxides

Efficient Decarboxylative/Defluorinative Alkylation for the Synthesis of gem-Difluoroalkenes through an SN2’-Type Route

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Chinese Journal of Chemistry 2022年第3期40卷 323-328页

作者： Wei-Long Xing Jia-Xin Wang ming-Chen fu Yao fu Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyiChEMUniversity of Science and Technology of ChinaHefeiAnhui 230026China

An efficient decarboxylative/defluorinative alkylation for synthesizing gem-difluoroalkenes is described,providing a general method for installation of the challenging alkyl fragments containing a-electron-withdrawing groups into a-trifluoromethyl *** studies suggest that this process involves an SN2,-type synthetic route in the absence of transition-metal catalysts or ***,this protocol can easily be scaled up,and successfully applied to the modification of biologically active molecules,thus complementing methodologies that give access to structurally versatile gem-difluoroalkenes.

关键词： Decarboxylation!Defluorination Alkylation C-C coupling Carboxylic acids

Grain size effect on the assembly quality of micro-scaled barrel formed by microforming

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Advances in Manufacturing 2024年第1期12卷 19-32页

作者： Dien Hu Jieyichen Fang Feng Zeng ming-Wang fu Department of Mechanical Engineering Research Institute of Advanced ManufacturingThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China Xiamen Yulong Machinery Co.Ltd. Xiamen361023FujianPeople’s Republic of China

In this research,a method employing micro-extrusion was designed to produce the micro-scaled barrel-shaped parts with complex geometrical features to study the feasibility of the proposed microforming method and its grain size effect on the formability of the complicated internal features in terms of deformation behavior,material evolution,accuracy of dimensions and final components *** results reveal that the deformation behavior is highly affected by grain size and becomes unpredictable with increased grain *** addition,assembly parameters including feature dimension,tolerance and coaxiality also vary with grain size,and the variation of grain size needs to be accommodated by different assembly types,viz.,clearance fit or transition *** the microstructural evolution aspect,it was identified there were two dead zones and four shear bands,and the formation of these deformation zones was barely affected by the variation in grain *** bulges,cracks,and fracture induced voids were observed on the surface of the final components,tailoring the microstructure of the working material with finer grains could significantly avoid these *** study advances the understanding of forming microparts by extrusion processes and provides guidance for microforming of similar microparts.

关键词： Microformed part Size effect Extrusion Microstructural evolution Dimensions Assembly accuracy

Effect of Al content in molten steel on interaction between MgO-C refractory and SPHC steel

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Journal of Iron and Steel Research International 2024年第4期31卷 838-848页

作者： fu-bin Gao fu-ming Wang Xiang Zhang Tian-yu Du Xin-hua Wangg School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Handan Iron and Steel Company Hegang GroupHandan 056015HebeiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The effect of Al content in molten steel on the interaction between SPHC steel(0.005-0.068 wt.%Al,and 19×10^(-4)-58×10^(-4)wt.%O)and MgO-C refractory(11.63 wt.%C)was ***-metallic inclusions in the steel were examined at various periods(0,5,15,30,45,and 60 min)as well as the MgO-C interface after 60 min of corrosion at 1600℃.The results show that when MgO-C refractory comes into contact with SPHC steel,the refractory interface consists of three layers arranged from the innermost to the outermost,including the original refractory layer,the dense MgO layer,and the iron infiltration *** carbon in the MgO-C refractories and the Al content in the molten steel undergo a reaction with the MgO in the refractories,resulting in an increase in Mg concentration in the *** Al content in the molten steel from 0.005 to 0.068 wt.%causes a spinel layer to appear at the interface,and the disappearance time of Al_(2)O_(3) inclusions in the steel decreases from 60 to 30 min,while the average MgO content in inclusions ***,controlling the Al content in the molten steel and the smelting duration can help regulate the formation of spinel inclusionsinthe steel.

关键词： MgO-C refractory SPHC steel Inclusion-Spinel Al-killed steel Interfacial reaction

Laboratory-scale column study for remediation of TCE-contaminated aquifers using three-section controlled-release potassium permanganate barriers

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Journal of Environmental Sciences 2013年第5期25卷 971-977页

作者： Baoling Yuan Fei Li Yanmei Chen ming-Lai fu Institute of Municipal and Environmental Engineering College of Civil EngineeringHuaqiao University College of Civil Engineering Fuzhou University Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences

A laboratory-scale study with a sand column was designed to simulate trichloroethylene（TCE） pollution in the aquifer environment with three-section controlled-release potassium permanganate（CRP） *** main objective of this study was to evaluate the feasibility of CRP barriers in remediation of TCE in aquifers in a long-term and controlled *** particles with a 1：3 molar ratio of KMnO 4 to stearic acid showed the best controlled-release properties in pure water,and the theoretical release time was 138.5 *** results of TCE removal in the test column indicated that complete removal efficiency of TCE in a sand column by three-section CRP barriers could be reached within 15 *** molar ratio of KMnO 4 to TCE in the three-section CRP barriers was 16：1,which was much lower than 82：1 as required when KMnO 4 solution is used directly to achieve complete destruction of *** result revealed that the efficiency of CRP for remediation of TCE was highly improved after encapsulation.

关键词： chlorinated solvent encapsulation groundwater KMnO 4 permeable reactive barrier sand column

Formation Control for Water-Jet USV Based on Bio-Inspired Method

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China Ocean Engineering 2018年第1期32卷 117-122页

作者： fu ming-yu WANG Duan-song WANG Cheng-long College of Automation Harbin Engineering University

The formation control problem for underactuated unmanned surface vehicles(USVs) is addressed by a distributed strategy based on virtual leader strategy. The control system takes account of disturbance induced by external environment. With the coordinate transformation, the advantage of the proposed scheme is that the control point can be any point of the ship instead of the center of gravity. By introducing bio-inspired model, the formation control problem is addressed with backstepping method. This avoids complicated computation, simplifies the control law,and smoothes the input signals. The system uniform ultimate boundness is proven by Lyapunov stability theory with Young inequality. Simulation results are presented to verify the effectiveness and robust of the proposed controller.

关键词： water-jet USV bio-inspired model backstepping formation control

Multi-Behavior fusion Based Potential Field Method for Path Planning of Unmanned Surface Vessel

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China Ocean Engineering 2019年第5期33卷 583-592页

作者： fu ming-yu WANG Sha-sha WANG Yuan-hui College of Automation Harbin Engineering University

The problem of the unmanned surface vessel (USV) path planning in static and dynamic obstacle environments is addressed in this paper. Multi-behavior fusion based potential field method is proposed, which contains three behaviors: goal-seeking, boundary-memory following and dynamic-obstacle avoidance. Then, different activation conditions are designed to determine the current behavior. Meanwhile, information on the positions, velocities and the equation of motion for obstacles are detected and calculated by sensor data. Besides, memory information is introduced into the boundary following behavior to enhance cognition capability for the obstacles, and avoid local minima problem caused by the potential field method. Finally, the results of theoretical analysis and simulation show that the collision-free path can be generated for USV within different obstacle environments, and further validated the performance and effectiveness of the presented strategy.

关键词： USV path planning potential field method multi-behavior fusion activation conditions local minima

High order symplectic conservative perturbation method for time-varying Hamiltonian system

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Acta Mechanica Sinica 2012年第3期28卷 885-890页

作者： ming-Hui fu Ke-Lang Lu Lin-Hua Lan Department of Applied Mechanics and Engineering Sun Yat-sen University510275 GuangzhouChina

This paper presents a high order symplectic con- servative perturbation method for linear time-varying Hamil- tonian system. Firstly, the dynamic equation of Hamilto- nian system is gradually changed into a high order pertur- bation equation, which is solved approximately by resolv- ing the Hamiltonian coefficient matrix into a ＂major compo- nent＂ and a ＂high order small quantity＂ and using perturba- tion transformation technique, then the solution to the orig- inal equation of Hamiltonian system is determined through a series of inverse transform. Because the transfer matrix determined by the method in this paper is the product of a series of exponential matrixes, the transfer matrix is a sym- plectic matrix; furthermore, the exponential matrices can be calculated accurately by the precise time integration method, so the method presented in this paper has fine accuracy, ef- ficiency and stability. The examples show that the proposed method can also give good results even though a large time step is selected, and with the increase of the perturbation or- der, the perturbation solutions tend to exact solutions rapidly.

关键词： Time-varying Hamiltonian system High ordermultiplicative perturbation Symplectic conservation expo-nential matrix Precise time integration method