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Inter-stage performance and energy characteristics analysis of electric submersible pump based on entropy production theory
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作者 Hui Wang Yang Yang +5 位作者 Bin Xi Wei-Dong Shi Chuan Wang Lei-Lei Ji Xiang-Yu Song Zhao-Ming He 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1354-1368,共15页
The electric submersible pump(ESP) is a crucial apparatus utilized for lifting in the oil extraction process.Its lifting capacity is enhanced by the multi-stage tandem structure, but variations in energy characteristi... The electric submersible pump(ESP) is a crucial apparatus utilized for lifting in the oil extraction process.Its 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. 展开更多
关键词 Electric submersible pump(ESP) entropy production theory Energy characteristics Inter-stage differences
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Blade Wrap Angle Impact on Centrifugal Pump Performance:Entropy Generation and Fluid-Structure Interaction Analysis
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作者 Hayder Kareem Sakran Mohd Sharizal Abdul Aziz Chu Yee Khor 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期109-137,共29页
The centrifugal pump is a prevalent power equipment widely used in different engineering patterns,and the impeller blade wrap angle significantly impacts its performance.A numerical investigation was conducted to anal... The centrifugal pump is a prevalent power equipment widely used in different engineering patterns,and the impeller blade wrap angle significantly impacts its performance.A numerical investigation was conducted to analyze the influence of the blade wrap angle on flow characteristics and energy distribution of a centrifugal pump evaluated as a low specific speed with a value of 69.This study investigates six impellermodels that possess varying blade wrap angles(95°,105°,115°,125°,135°,and 145°)that were created while maintaining the same volute and other geometrical characteristics.The investigation of energy loss was conducted to evaluate the values of total and entropy generation rates(TEG,EGR).The fluid-structure interaction was considered numerically using the software tools ANSYS Fluent and ANSYSWorkbench.The elastic structural dynamic equation was used to estimate the structural response,while the shear stress transport k–ωturbulence model was utilized for the fluid domain modeling.The findings suggest that the blade wrap angle has a significant influence on the efficiency of the pump.The impeller featuring a blade wrap angle of 145°exhibits higher efficiency,with a notable increase of 3.76%relative to the original model.Variations in the blade wrap angle impact the energy loss,shaft power,and pump head.The model with a 145°angle exhibited a maximum equivalent stress of 14.8MPa and a total deformation of 0.084 mm.The results provide valuable insights into the intricate flow mechanism of the centrifugal pump,particularly when considering various blade wrap angles. 展开更多
关键词 Centrifugal pump blade wrap angle entropy generation theory fluid-structure interaction hydraulic performance
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The Source of Groundwater Recharge Based on Entropy Theory in the Arid Areas of North China 被引量:1
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作者 CHEN Jiansheng XU Yi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期390-391,共2页
Objective Any natural system is constantly exchanging material, energy and information with the environment, and all tkese processes follow the basic law of thermodynamics, with no exception of groundwater recharge a... Objective Any natural system is constantly exchanging material, energy and information with the environment, and all tkese processes follow the basic law of thermodynamics, with no exception of groundwater recharge and discharge process. On the basis of the principle of the first law of thermodynamics, the reverse geochemical simulation method is widely used in the study of groundwater recharge, runoff and drainage process. However, some studies only consider the material conservation in theprocess, but ignore the probability of the transformation. 展开更多
关键词 The Source of Groundwater Recharge Based on entropy theory in the Arid Areas of North China
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Improved HVSR site classification method for free-field strong motion stations validated with Wenchuan aftershock recordings 被引量:16
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作者 Wen Ruizhi Ren Yefei Shi Dacheng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2011年第3期325-337,共13页
Local site conditions play an important role in the effective application of strong motion recordings.In the China National Strong Motion Observation Network System(NSMONS),some of the stations do not provide boreho... Local site conditions play an important role in the effective application of strong motion recordings.In the China National Strong Motion Observation Network System(NSMONS),some of the stations do not provide borehole information,and correspondingly,do not assign the site classes yet.In this paper,site classification methodologies for free-field strong motion stations are reviewed and the limitations and uncertainties of the horizontal-to-vertical spectral ratio(HVSR) methods are discussed.Then,a new method for site classification based on the entropy weight theory is proposed.The proposed method avoids the head or tail joggle phenomenon by providing the objective and subjective weights.The method was applied to aftershock recordings from the 2008 Wenchuan earthquake,and 54 free-field NSMONS stations were selected for site classification and the mean HVSRs were calculated.The results show that the improved HVSR method proposed in this paper has a higher success rate and could be adopted in NSMONS. 展开更多
关键词 site classification strong motion recording entropy weight theory horizontal-to-vertical spectrum ratio Wenchuan earthquake aftershock head-tail joggle
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Bedload Sediment Rate Prediction for the Sand Transport Along Coastal Waters in Ocean Management Strategy 被引量:2
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作者 Saeed KHORRAM 《China Ocean Engineering》 SCIE EI CSCD 2020年第6期840-852,共13页
Interactions among different landforms and varied complicated physical processes cause sediment transport in coastal regions being the interest of ocean management planning studies. In coastal zones, the derivation of... Interactions among different landforms and varied complicated physical processes cause sediment transport in coastal regions being the interest of ocean management planning studies. In coastal zones, the derivation of the bedload sediment transport rate and the flow velocity distribution is done by entropy theory which assumes the modified spatiotemporal disorder power index(MSTDPI) and the time-averaged flow velocity(as a random variable). Studying the deposition trend of bedload sediment transport rate for the sand particle(BLSTRS) and estimating the coastal erosion rate as a case study, the Makran coast is selected. To analyze the spatiotemporal patterns, the disorder power index(entropy-power) method is applied in this study where the monthly data of six Makran coastal sections from January 1970 to December 2015 are used. The studied data are mainly focused on the correlation of the flow rate of the sediment from the Makran River, and the spatiotemporal patterns of BLSTRS.Despite their meaningful spatiotemporal variability, it is not very easy to explain how the abovementioned variables perform together;the entropy-power index allows a better understanding of the combined performance of such parameters as the flow velocity and sediment transport by showing clearer signals for the assessment of coastal engineering issues at very large(coastal) scales. 展开更多
关键词 flow velocity SPATIOTEMPORAL entropy theory coastline zone
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ENTROPY THEORY AND PARAMETERIZATION OF NONUNIFORM DISTRIBUTION OF PRECIPITATION 被引量:1
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作者 张正秋 李维亮 《Acta meteorologica Sinica》 SCIE 1998年第3期334-344,共11页
In this paper a parameterization of nonuniform distribution of precipitation has been made from the aspect of the maximum entropy theory.Results from theory and observation show that, the density function of precipita... In this paper a parameterization of nonuniform distribution of precipitation has been made from the aspect of the maximum entropy theory.Results from theory and observation show that, the density function of precipitation depth on the subgrid scale over the grid area of a climate model is the function of the gamma distribution.On this basis,the relative coverage of snow in the region occupied by vegetation in the grid area of a model is parameterized.Meanwhile the calculated results from the parameterizations are also compared with those from the empirical formulas by some other meteorologists.Results show that it is feasible to parameterize the nonuniform distribution of precipitation over the grid area at the angle of entropy theory. 展开更多
关键词 entropy theory grid area precipitation distribution PARAMETERIZATION
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Thermodynamic properties of ZnSe under pressure and with variation in temperature
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作者 Najm Ul Aarifeen A Afaq 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期144-147,共4页
The thermodynamic properties of Zn Se are obtained by using quasi-harmonic Debye model embedded in Gibbscode for pressure range 0–10 GPa and for temperature range 0–1000 K. Helmholtz free energy, internal energy, en... The thermodynamic properties of Zn Se are obtained by using quasi-harmonic Debye model embedded in Gibbscode for pressure range 0–10 GPa and for temperature range 0–1000 K. Helmholtz free energy, internal energy, entropy,Debye temperature, and specific heat are calculated. The thermal expansion coefficient along with Gruneisen parameter are also calculated at room temperature for the pressure range. It is found that internal energy is pressure dependent at low temperature, whereas entropy and Helmholtz free energy are pressure sensitive at high temperature. At ambient conditions,the obtained results are found to be in close agreement to available theoretical and experimental data. 展开更多
关键词 density functional theory Helmholtz energy Debye temperature entropy
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The Entropies Evaluation of the High-entropy System and its Determination of Operating Entropy 被引量:8
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作者 SONG Hua\|ling\+1,\ ZHAI Cong\|min 2,\ LIU Li\|juan 21.School of management, Hebei University of Technology Cornelis Reiman, Tianjin 300130, China Department of Management, Monash University, Australia 2.School of management, Hebei University of T 《Systems Science and Systems Engineering》 CSCD 2000年第3期315-323,共9页
This article applies the basic principles of the general and special entropy, puts forward the concept of High\|entropy system and its entropies. Sometimes, the entropy functions have been defined, and their mathemati... This article applies the basic principles of the general and special entropy, puts forward the concept of High\|entropy system and its entropies. Sometimes, the entropy functions have been defined, and their mathematical models have been constructred, and methods of quantification. Specially. Taking the Mining System as an example, the quantification method of the operating entropy is given under the synthetic action of the man\|made entropy, machine entropy, natural entropy and environmnet entropy. Therefore it enriches the theoretical and applied systems of the general and special entropy. 展开更多
关键词 general and special entropy theories high\|entropy system operating entropy manmade entropy natural entropy environment entropy
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Insight on Viscoelasticiy of Ti16.7Zr16.7Hf16.7Cu16.7Ni16.7Be16.7 High Entropy Bulk Metallic Glass
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作者 Ji-chao QIAO Jean-marc PELLETIER +1 位作者 Ning LI Yao YAO 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第1期19-23,共5页
High entropy bulk metallic glasses show promising mechanical and physical properties.Dynamic mechanical properties of Ti_(16.7)Zr_(16.7)Hf_(16.7)Cu_(16.7)Ni_(16.7)Be_(16.7)high entropy bulk metallic glass ... High entropy bulk metallic glasses show promising mechanical and physical properties.Dynamic mechanical properties of Ti_(16.7)Zr_(16.7)Hf_(16.7)Cu_(16.7)Ni_(16.7)Be_(16.7)high entropy bulk metallic glass were investigated by mechanical spectroscopy(or called dynamic mechanical analysis).The main(α)relaxation was observed in the framework of the loss modulus G″,which is related to the dynamic glass transition behaviour for the glassy materials.From physical model point of view,dynamic mechanical properties of the Ti_(16.7)Zr_(16.7)Hf_(16.7)Cu_(16.7)Ni_(16.7)Be_(16.7)high entropy bulk metallic glass show good agreement compared with the quasi-point defects theory. 展开更多
关键词 high entropy bulk metallic glass viscoelasticity mechanical spectroscopy quasi-point defect theory
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Optimization of Group Multiattribute Decision-Making Model in Commercial Space Investment
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作者 张一鸣 侯俊杰 钟少文 《Journal of Shanghai Jiaotong university(Science)》 EI 2023年第6期831-840,共10页
A group multiattribute decision-making model was proposed by implementing prospect theory,multi-attribute decision-making,group decision-making and entropy methods for the optimization in commercial space investment.F... A group multiattribute decision-making model was proposed by implementing prospect theory,multi-attribute decision-making,group decision-making and entropy methods for the optimization in commercial space investment.First,the decision-making function was decided using prospect theory by the preference of each expert to reach the comprehensive prospect value based on different investment options;second,expert decision weights were reached according to entropy method;third,the expert group decision-making information was congregated according to the group decision-making congregation algorithm to reach the most optimized investment option;finally,an example was given to demonstrate the feasibility and effectiveness of the method.This model com-prehensively takes the advantages of many methods to congregate experts'experiences and avoid the subjective influences,thus providing a scientific decision-making approach for the commercial space investment. 展开更多
关键词 commercial space investment multiattribute decision-making group decision-making prospect theory entropy theory
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Prediction of extreme wind velocity at the site of the Runyang Suspension Bridge 被引量:6
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作者 Yang DENG You-liang DING Ai-qun LI Guang-dong ZHOU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2011年第8期605-615,共11页
This paper presents a distribution free method for predicting the extreme wind velocity from wind monitoring data at the site of the Runyang Suspension Bridge (RSB), China using the maximum entropy theory. The maximum... This paper presents a distribution free method for predicting the extreme wind velocity from wind monitoring data at the site of the Runyang Suspension Bridge (RSB), China using the maximum entropy theory. The maximum entropy theory is a rational approach for choosing the most unbiased probability distribution from a small sample, which is consistent with available data and contains a minimum of spurious information. In this paper, the theory is used for estimating a joint probability density function considering the combined action of wind speed and direction based on statistical analysis of wind monitoring data at the site of the RSB. The joint probability distribution model is further used to estimate the extreme wind velocity at the deck level of the RSB. The results of the analysis reveal that the probability density function of the maximum entropy method achieves a result that fits well with the monitoring data. Hypothesis testing shows that the distributions of the wind velocity data collected during the past three years do not obey the Gumbel distribution. Finally, our comparison shows that the wind predictions of the maximum entropy method are higher than that of the Gumbel distribution, but much lower than the design wind speed. 展开更多
关键词 Extreme wind velocity Maximum entropy theory Probability density function Structural health monitoring(SHM)
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Attribute reduction in interval-valued information systems based on information entropies 被引量:9
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作者 Jian-hua DAI Hu HU +3 位作者 Guo-jie ZHENG Qing-hua HU Hui-feng HAN Hong SHI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第9期919-928,共10页
Interval-valued data appear as a way to represent the uncertainty affecting the observed values. Dealing with interval-valued information systems is helpful to generalize the applications of rough set theory. Attribut... Interval-valued data appear as a way to represent the uncertainty affecting the observed values. Dealing with interval-valued information systems is helpful to generalize the applications of rough set theory. Attribute reduction is a key issue in analysis of interval-valued data. Existing attribute reduction methods for single-valued data are unsuitable for interval-valued data. So far, there have been few studies on attribute reduction methods for interval-valued data. In this paper, we propose a framework for attribute reduction in interval-valued data from the viewpoint of information theory. Some information theory concepts, including entropy, conditional entropy, and joint entropy, are given in interval-valued information systems. Based on these concepts, we provide an information theory view for attribute reduction in interval-valued information systems. Consequently, attribute reduction algorithms are proposed. Experiments show that the proposed framework is effective for attribute reduction in interval-valued information systems. 展开更多
关键词 Rough set theory Interval-valued data Attribute reduction entropy
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A moment-based stochastic edge-based smoothed finite element method for electromagnetic forming process
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作者 YANG Qin WANG Bing +1 位作者 LI She CUI XiangYang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2020年第9期1739-1750,共12页
In this paper, a novel stochastic method named as the moment-based stochastic edge-based finite element method(MSES-FEM)is proposed to deal with the uncertain electromagnetic problems. First, electromagnetic and mecha... In this paper, a novel stochastic method named as the moment-based stochastic edge-based finite element method(MSES-FEM)is proposed to deal with the uncertain electromagnetic problems. First, electromagnetic and mechanical field are formulated by smoothed Galerkin Weak Form under edge-based smoothed finite element method(ES-FEM) scheme. The moment analysis is then applied to obtain the first four moments of the responses and to observe the effects of each random variable on electromagnetic field responses. The maximum entropy theory is employed to calculate the probability density functions(PDFs) of the responses. A quasi-static electromagnetic problem and a practical electromagnetic forming problem(EMF) are performed. The proposed method successfully solves stochastic electromagnetic forming analysis under the uncertain parameters. Numerical results obtained by the proposed MSES-FEM are quite satisfactory with the ones by the Monte Carlo simulation(MCS). 展开更多
关键词 MSES-FEM electromagnetic forming problem the moment analysis the maximum entropy theory probability density function
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Pseudo-derivative evolutionary algorithm and convergence analysis
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作者 Yang Yu Zhongjie Wang +1 位作者 Huaglory Tianfield Chengchao Lu 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2018年第5期92-107,共16页
In this paper,a novel evolutionary algorithm(EA),called pseudo-derivative EA(called PDEA),is proposed.The basic idea of PDEA is to use pseudo-derivative,which is obtained based on the information produced during the e... In this paper,a novel evolutionary algorithm(EA),called pseudo-derivative EA(called PDEA),is proposed.The basic idea of PDEA is to use pseudo-derivative,which is obtained based on the information produced during the evolution,and to help search the solution of optimization problem.The pseudo-derivative drives the search process in a more informed direction.That makes PDEA different from the random optimization methods.The convergence of PDEA is first analyzed based on systems theory.The convergence condition of PDEA is then derived though this condition is too strong to be satisfied.Next,this condition is relaxed based on the entropy theory.Finally,performances of PDEA are evaluated on the benchmark functions and an adaptive liquid level control system of a surge tank.The numeric simulation results show that PDEA is capable of finding the solutions to the optimization problems with good accuracy,reliability,and speed. 展开更多
关键词 Evolutionary algorithm convergence analysis entropy theory pseudoderivative.
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