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Inter-stage performance and energy characteristics analysis of electric submersible pump based on entropy production theory

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Petroleum Science 2024年第2期21卷 1354-1368页

作者： Hui Wang Yang Yang Bin Xi wei-dong shi Chuan Wang Lei-Lei Ji Xiang-Yu Song Zhao-Ming He College of Hydraulic Science and Engineering Yangzhou UniversityYangzhou225009JiangsuChina College of Electrical and Mechanical Engineering Nanchang Institute of TechnologyNanchang330044JiangxiChina College of Mechanical Engineering Nantong UniversityNantong226019JiangsuChina National Research Center of Pumps Jiangsu UniversityZhenjiang212013JiangsuChina Zhejiang Zhenxing Petrochemical Machinery Co. Ltd.Ruian325204ZhejiangChina Department of Mechanical Engineering of Texas Tech University Lubbock79411TXUSA

The electric submersible pump(ESP) is a crucial apparatus utilized for lifting in the oil extraction *** lifting capacity is enhanced by the multi-stage tandem structure, but variations in energy characteristics and internal flow across stages are also introduced. In this study, the inter-stage variability of energy characteristics in ESP hydraulic systems is investigated through entropy production(EP) analysis,which incorporates numerical simulations and experimental validation. The EP theory facilitates the quantification of energy loss in each computational subdomain at all ESP stages, establishing a correlation between microscopic flow structure and energy dissipation within the system. Furthermore, the underlying causes of inter-stage variability in ESP hydraulic systems are examined, and the advantages and disadvantages of applying the EP theory in this context are evaluated. Consistent energy characteristics within the ESP, aligned with the distribution of internal flow structure, are provided by the EP theory, as demonstrated by our results. The EP theory also enables the quantitative analysis of internal flow losses and complements existing performance analysis methods to map the internal flow structure to hydraulic losses. Nonetheless, an inconsistency between the energy characterization based on EP theory and the traditional efficiency index when reflecting inter-stage differences is identified. This inconsistency arises from the exclusive focus of the EP theory on flow losses within the flow field, disregarding the quantification of external energy input to the flow field. This study provides a reference for the optimization of EP theory in rotating machinery while deeply investigating the energy dissipation characteristics of multistage hydraulic system, which has certain theoretical and practical significance.

关键词： Electric submersible pump(ESP) Entropy production theory Energy characteristics Inter-stage differences

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Theory and Experimental Verification on Cymbal-shaped Slotted Valve Piezoelectric Pump

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 212-219页

作者： Jun Huang Yi-Chao Zhu wei-dong shi Jian-Hui Zhang National Research Center of Pumps Jiangsu University College of Mechanical and Electrical Engineering Guangzhou University

Valve piezoelectric pumps usually have larger flow rate than that of valveless ones. However, the traditional cantilever valve easily induces stress concentration which impacts the reliability of pumps. Therefore, a cymbal-shaped slotted check valve is proposed to be applied in a piezoelectric pump in order to reduce the stress concentration of the valve and thus improve the reliability of the piezoelectric pump. The structure and working principle of the piezoelectric pump are analyzed; the stress analysis of the cymbal-shaped slotted valve diaphragm is conducted. In addition, finite element software is employed to analyze the difference of the Von-Mises stress between the cymbal-shaped slotted diaphragm and the slotted flat diaphragm. The simulation results show that, the Von-Mises stress of cymbal-shaped slotted diaphragm is smaller than that of the slotted flat one. Furthermore, the cymbal-shaped slotted valve piezoelectric pump is also fabricated, and flow rate experiment is performed. The experimental results indicate that the flow rate of piezoelectric pump working in low frequencies(0 Hz < f< 50 Hz) is larger than that working in high frequencies(200 Hz < f< 2000 Hz). When driven at voltage of 160 V and frequency of 5 Hz, the pump reaches its maximum flow rate of 6.6 g/min. The experimental results validate the feasibility of the cymbal-shaped slotted check valve. This research can effectively solve the problem of stress concentration of valve piezoelectric pumps and is helpful for improving the reliability of them.

关键词： Cymbal-shaped slotted Piezoelectric pump Valve Stress

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Study on Applying Optimal Path to Land Valuation

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Geo-Spatial Information Science 2006年第1期9卷 49-54页

作者： WANG wei dong Fei shi Lite CAO Fang State Key Laboratory of Information Engeering in Surveying. Mapping and Remote Sensing. Wuhan University 129 Luoyu Road Wuhan 430079 China

As an important role in the urban land price system, the basic land price appraisal directs and refleets all kinds of land price in the real estate market. Using geographic information systems （GIS） with algo rithms and powerful analysis functions to valuate land will improve the rationality and convenience of land valu- ation. The objective of the study on basic land price using the optimal path algorithm is to decrease the man made error, enhance automatization, avoid make inconvenience by roadblock object.

关键词： GIS optimal path shortest path land price appraisal land valuation basic land price

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Overexpression of a Foreign Bt Gene in Cotton Affects the Low-Molecular-weight Components in Root Exudates

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Pedosphere 2007年第3期17卷 324-330页

作者： YAN wei-dong shi wei-Ming LI Bao-Hai ZHANG Min State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing210008 （China）

Most research in the past using genetically modified crops (GM crops) has focused on the ecological safety of foreign gene (i.e., the gene flow), gene products (for example, Bt (Bacillus thuringiensis) protein), and the safety of transgenic food for humans. In this study, changes in both the species and amounts of low-molecular-weight components in cotton (Gossypium hirsutum L.) root exudates after foreign Bt gene overexpression were investigated under different nutritional conditions. Transgenic cotton containing Bt (Bt-cotton), supplemented with all the mineral nutrients, secreted more organic acids than the wild-type cotton (WT). When nitrogen was removed from the full-nutrient solution, the amount of organic acids secretion of Bt-cotton was lesser than that of WT. The roots of the transgenic cotton secreted lesser amounts of amino acids and soluble sugars than the WT roots in the full-nutrient solution. Deficiencies of P and K caused a large increase in the total amino acid and soluble sugar secretions of both Bt-cotton and WT, with larger increases observed in Bt-cotton. Because transferring the foreign Bt gene into cotton can result in alterations in the components of the root exudates, with the effect varying depending on the nutritional status, the cultivation of genetically modified crops, such as Bt-cotton, in soil environments should be more carefully assessed, and the possible effects as a result of the alterations in the root exudate components should be considered.

关键词： gene overexpression low-molecular-weight components nutritional status root exudates transgenic cotton

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Hydroxylation of 3-nitrotyrosine by hydroxyl radical

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Chinese Chemical Letters 2007年第5期18卷 542-544页

作者： Jun Chen dong wei Qun shi Yu Fen Zhao Yan Mei Li Key Laboratory of Bioorganic Phosphorous Chemistry ＆ Chemical Biology （Ministry of Education） Department of Chemistry Tsinghua University Beijing 100084 China

Hydroxylation of 3-nitrotyrosine （3-NT） and 3-NT containing peptide Gly-nitroTyr-Gly in aqueous solution by hydroxyl radical were investigated with gamma irradiation. The structures of the hydroxylated products were confirmed by electrospray ionization mass spectrometry and ^1H NMR spectrometry. The reactivity of 3-nitrotyrosine has been investigated using density functional theory （DFT） calculation.

关键词： 3-Nitrotyrosine Hydroxyl radical DFT Selective hydroxylation

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Synthesis,Biological Evaluation and Molecular Modeling of Cyclic Tetrapeptide Based Inhibitors HDAC

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Chemical Research in Chinese Universities 2012年第6期28卷 1011-1016页

作者： LI Xiao-hui wei Ying-dong WANG shi-miao WANG Meng-nan HUANG Da-wei XIU Zhi-long School of Life Science and Biotechnology Dalian University of Technology Dalian 116024 P. R. China

Histone deacetylases（HDACs） are considered to be among the most promising targets for the development of anti-cancer drugs,and HDAC inhibitors（HDACIs） have become a promising class of anti-cancer *** explore whether thioacetyl group as the zinc binding group（ZBG） and a slight change in the hydrophobicity of the recognition domain of HDACIs could alter their activities,we synthesized a series of cyclo[-L-Am7（SAc）-Aib-L-Phe（n-Cl）D-Pro-] and evaluated their HDAC-inhibitory and antiproliferative *** results show that these peptides could inhibit HDAC at 10-9 mol/L level,and could selectively inhibit the proliferation of three human cancer cell lines with IC 50 at 10-6 mol/L *** study was conducted to examine the mechanisms by which these peptides interact with *** appeared that a zinc ion in the active site of HDAC was coordinated by the carbonyl oxygen atom of the ZBG in the *** the ZBG domain of all the peptides and the surface recognition domain of cyclo[-L-Am7（SAc）-Aib-L-Phe（o-Cl）-D-Pro-] and that of cyclo[-L-Am7（SAc）-Aib-L-Phe（m-Cl）-D-Pro-] interacted with HDAC2 via hydrogen *** interaction has been considered to provide favorable contributions to stabilizing the complexes,and the introduction of a chlorine atom at the aromatic ring on the L-Phe position of these peptides affected the interaction between each of these inhibitors and the enzyme,resulting in slight change in the structure of the surface recognition domain of the peptides.

关键词： Histone deacetylase(HDAC) Histone deacetylase inhibitor(HDACI) Cyclic tetrapeptide Anti-cancer agent Antiproliferative activity Docking

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An approximate analytical model for unconventional reservoir considering variable matrix blocks and simultaneous matrix depletion

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Petroleum Science 2024年第1期21卷 352-365页

作者： Kai-Xuan Qiu Jia Li dong Feng shi-Ming wei Gang Lei Jiangmen Laboratory of Carbon Science and Technology Jiangmen529100GuangdongChina The Hong Kong University of Science and Technology(Guangzhou) Guangzhou511400GuangdongChina China University of Geosciences(Beijing) Beijing100083China China University of Petroleum(Beijing) Beijing102249China China University of Geosciences(Wuhan) Wuhan430074HubeiChina Shenzhen Research Institute China University of GeosciencesShenzhen518063GuangdongChina

In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture *** has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture *** addition,most of the existing models are solved analytically based on Laplace transform and numerical ***,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix *** simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the ***,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by ***,a relationship between oil rate and production time in real-time space is *** new model is verified against classical analytical *** the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,***,the new model also has an excellent agreement with the numerical *** model is then applied to two actual tight oil wells completed in western Canada sedimentary *** identifying the flow regime,the solution suitably matches the field production data,and the model parameters are *** these output parameters,we can accurately forecast the production and even estimate the petrophysical properties.

关键词： Analytical solution Unconventional reservoir Variable matrix Simultaneous flow

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Fabrication and evaluation of molecularly imprinted regenerated cellulose composite membranes via atom transfer radical polymerization

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Chinese Chemical Letters 2014年第2期25卷 273-278页

作者： Yi-Lin Wu Yong-Sheng Yan Jian-Ming Pan Xiao-Hui Dai wei-dong shi Min-Jia Meng School of Chemistry and Chemical Engineering Jiangsu University

A simple and effective method for surface molecularly imprinted composite membranes （MICMs） for artemisinin （Ars） based on regenerated cellulose membranes was first prepared through surface- initiated atom transfer radical polymerization （ATRP）, and the as-prepared MICMs were then evaluated as adsorbents for selective recognition and separation of Ars molecules. Batch rebinding studies were conducted to determine the specific adsorption equilibrium, kinetics and selective permeation performance. The adsorption capacity of MICMs toward Ars by the Langmuir isotherm model was 2.008 mgg-1, which was nearly 5.0 times higher than non-molecularly imprinted composite membranes （NICMs）. The kinetic property of MICMs was well-fitted by the pseudo-second-order rate equation. The selective permeation experiments were successfully investigated to prove the excellent selective permeation performance for Ars than the competitive analog （artemether）.

关键词： Molecularly imprinted compositemembranes Atom transfer radical polymerization Selective recognition Artemisinin

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Finite element analysis of high-pressure hose for radial horizontal wells in coalbed methane extraction

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Journal of Coal Science & Engineering(China) 2013年第2期19卷 182-186页

作者： wei-dong ZHOU wei shi Luo-Peng LI Jing-Shuang WANG Jun SUN College of Petroleum Engineering China University of Petroleum (East China) Dongying 257061 China

Based on the serial-parallel model of single-layer board and the lamination theory, the forces exerted on different layers of the high-pressure hose and the resulting deformations were analyzed when the hose was radially stretched. An equation was proposed to calculate the anisotropic elastic constant of the composite layer with the wound steel wires. Furthermore, the finite element analysis （FEA） model of the high-pressure hose was established, followed by a simulation of the forces that act on different layers, and their deformations. The simulation results show that the stress imposed on the inner reinforced layer and external reinforced layer of the high-pressure hose are approximately 150 MPa and 115 MPa, respectively, in the presence of inner pressure. The stress of the rubber coating and polyethylene coating is lower. The lowest stress occurs on the inner surface of the high-pressure hose and the rubber coating between the two composite layers. The deformation of the rubber layer in the inner surface of the high-pressure hose decreases gradually along the radial direction from the inner surface to the external surface. The deformation of the reinforced composite layer is less than that of the external surface of the rubber coating. The equivalent stress of the reinforced composite layer is higher than that caused by the inner pressure, due to the presence of both inner pressure and axial tension.

关键词： coalbed methane radial horizontal well high-pressure hose finite element analysis

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Searching for the optimal precondition procedure for mesenchymal stem/stromal cell treatment:Facts and perspectives

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World Journal of Stem Cells 2024年第6期16卷 615-618页

作者： Yu-dong Zhao Yong-Can Huang wei-shi Li Department of Orthopedic Peking University Third HospitalBeijing 100191China Shenzhen Engineering Laboratory of Orthopaedic Regenerative Technologies Orthopaedic Research CenterPeking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina

Mesenchymal stem/stromal cells are potential optimal cell sources for stem cell therapies,and pretreatment has proven to enhance cell vitality and *** a recent publication,Li et al explored a new combination of pretreatment ***,we present an editorial to comment on their work and provide our view on mesenchymal stem/stromal cell precondition.

关键词： Mesenchymal stem cell Precondition Hypoxia Inflammation

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