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Effect of bipolar-plates design on corrosion,mass and heat transfer in proton-exchange membrane fuel cells and water electrolyzers:A review
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作者 Jiuhong Zhang Xiejing Luo +2 位作者 Yingyu Ding Luqi Chang Chaofang Dong 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1599-1616,共18页
Attaining a decarbonized and sustainable energy system,which is the core solution to global energy issues,is accessible through the development of hydrogen energy.Proton-exchange membrane water electrolyzers(PEMWEs)ar... Attaining a decarbonized and sustainable energy system,which is the core solution to global energy issues,is accessible through the development of hydrogen energy.Proton-exchange membrane water electrolyzers(PEMWEs)are promising devices for hydrogen production,given their high efficiency,rapid responsiveness,and compactness.Bipolar plates account for a relatively high percentage of the total cost and weight compared with other components of PEMWEs.Thus,optimization of their design may accelerate the promotion of PEMWEs.This paper reviews the advances in materials and flow-field design for bipolar plates.First,the working conditions of proton-exchange membrane fuel cells(PEMFCs)and PEMWEs are compared,including reaction direction,operating temperature,pressure,input/output,and potential.Then,the current research status of bipolar-plate substrates and surface coatings is summarized,and some typical channel-rib flow fields and porous flow fields are presented.Furthermore,the effects of materials on mass and heat transfer and the possibility of reducing corrosion by improving the flow field structure are explored.Finally,this review discusses the potential directions of the development of bipolar-plate design,including material fabrication,flow-field geometry optimization using threedimensional printing,and surface-coating composition optimization based on computational materials science. 展开更多
关键词 bipolar-plates flow design mass and heat transfer CORROSION water electrolyzers fuel cells
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Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions
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作者 Xue-Ping Du Guang-Lei Yu +3 位作者 Ya-Cheng Xu Zhi-Jie Chen Nai-Liang Li Huan-Guang Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1333-1345,共13页
The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper stud... The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure drop.These results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions. 展开更多
关键词 Spiral-wound heat exchanger Sloshing conditions Two-phase flow MULTI-COMPONENT heat and mass transfer
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Modeling of Coupled Heat and Mass Transfer in a Trapezoidal Porous Bed on a Grid
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作者 Kokou N’Wuitcha Gagnon Koffi Apedanou +1 位作者 Yendoubé Lare Kossi Napo 《Open Journal of Fluid Dynamics》 CAS 2023年第1期1-15,共15页
We investigate heat and mass transfer in an isosceles trapezoidal cavity, filled with charcoal considered as a granular porous medium. The Darcy-Brinkman-Forchheimer flow model is coupled to the energy and mass equati... We investigate heat and mass transfer in an isosceles trapezoidal cavity, filled with charcoal considered as a granular porous medium. The Darcy-Brinkman-Forchheimer flow model is coupled to the energy and mass equations with the assumption of non-thermal equilibrium. These equations are discretized by the finite volume method with an offset mesh and then solved by the line-by-line method of Thomas. The coupling between pressure and velocity is obtained by Semi-Implicit Method for Pressure Linked Equations. (SIMPLE) algorithm. The results show that the temperature in the cavity increases when the inclination angle of the sides walls decreases. The 15° inclination is selected as being able to offer better thermal performance in the cookstove combustion chamber. 展开更多
关键词 heat and mass transfer Isosceles Trapezoidal Cavity Porous Medium Finite Volume Method SIMPLE Algorithm
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Influence of Anisotropic Permeability and Soret Effect on the Convective Heat and Mass Transfer through a Porous Cavity Saturated by a Non-Newtonian Fluid
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作者 Dieudonné Kouke Julien Yovogan 《Engineering(科研)》 2023年第12期843-866,共24页
In this work, an analytical study is carried out on double-diffusive natural convection through a horizontal anisotropic porous layer saturated with a non-Newtonian fluid by using the Darcy model with the Boussinesq a... In this work, an analytical study is carried out on double-diffusive natural convection through a horizontal anisotropic porous layer saturated with a non-Newtonian fluid by using the Darcy model with the Boussinesq approximations. The horizontal walls of the system are subject to vertical uniform fluxes of heat and mass, whereas the vertical walls are assumed to be adiabatic and impermeable. The Soret effect is taken into consideration. Based on parallel flow approximation theory, the problem is solved in the limit of a thin layer and documented the effects of the physical parameters describing this investigation. 展开更多
关键词 Soret Number heat and mass transfer Non-Newtonian Fluid ISOTROPY Ani-sotropy Supercritical Rayleigh Number
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Heat and Mass Transfers in a Two-Phase Stratified Turbulent Fluid Flow in a Geothermal Pipe with Chemical Reaction
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作者 Eric M. Nyariki Mathew N. Kinyanjui Jeconia O. Abonyo 《Journal of Applied Mathematics and Physics》 2023年第2期484-513,共30页
This research focused on the study of heat and mass transfers in a two-phase stratified turbulent fluid flow in a geothermal pipe with chemical reaction. The derived non-linear partial differential equations governing... This research focused on the study of heat and mass transfers in a two-phase stratified turbulent fluid flow in a geothermal pipe with chemical reaction. The derived non-linear partial differential equations governing the flow were solved using the Finite Difference Method. The effects of various physical parameters on the concentration, skin friction, heat, and mass transfers have been determined. Analysis of the results obtained indicated that the coefficient of skin friction decreased with an increase in Reynolds number and solutal Grasholf number, the rate of heat transfer increased with an increase in Eckert number, Prandtl number, and angle of inclination, and the rate of mass transfer increased with increase in Reynolds number, Chemical reaction parameter and angle of inclination. The findings would be useful to engineers in designing and maintaining geothermal pipelines more effectively. 展开更多
关键词 TWO-PHASE Turbulence Non-Newtonian INCLINATION heat transfer mass transfer STRATIFIED
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Analysis and modeling of alumina dissolution based on heat and mass transfer 被引量:3
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作者 詹水清 李茂 +2 位作者 周孑民 杨建红 周益文 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1648-1656,共9页
A comprehensive heat and mass transfer model of dissolution process of non-agglomerated and agglomerated alumina particles was established in an aluminum reduction cell. An appropriate finite difference method was use... A comprehensive heat and mass transfer model of dissolution process of non-agglomerated and agglomerated alumina particles was established in an aluminum reduction cell. An appropriate finite difference method was used to calculate the size dissolution rate, dissolution time and mass of alumina dissolved employing commercial software and custom algorithm based on the shrinking sphere assumption. The effects of some convection and thermal condition parameters on the dissolution process were studied. The calculated results show that the decrease of alumina content or the increase of alumina diffusion coefficient is beneficial for the increase of size dissolution rate and the decrease of dissolution time of non-agglomerated particles. The increase of bath superheat or alumina preheating temperature results in the increase of size dissolution rate and the decrease of dissolution time of agglomerated particles. The calculated dissolution curve of alumina(mass fraction of alumina dissolved) for a 300 k A aluminum reduction cell is in well accordance with the experimental results. The analysis shows that the dissolution process of alumina can be divided into two distinct stages: the fast dissolution stage of non-agglomerated particles and the slow dissolution stage of agglomerated particles, with the dissolution time in the order of 10 and 100 s, respectively. The agglomerated particles were identified to be the most important factor limiting the dissolution process. 展开更多
关键词 aluminum reduction cell alumina particles dissolution process heat and mass transfer finite difference method
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RHEOLOGICAL CHARACTERISTICS,POWER CONSUMPTION,MASS AND HEAT,TRANSFER DURING XANTHAN GUM FERMENTATION 被引量:4
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作者 赵学明 胡宗定 +2 位作者 A.W.Nienow C.A.Kent S.Chatwin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1994年第4期15-27,共13页
Xanthan gum fermentation is probably the most complex fermentation process in terms ofrheological property variations and associated mixing,power consumption,mass and heat transferproblems.In order to obtain these dat... Xanthan gum fermentation is probably the most complex fermentation process in terms ofrheological property variations and associated mixing,power consumption,mass and heat transferproblems.In order to obtain these data,fermentations of Xanthomonas campestris were carried outon pilot scale bioreactor with different D/T ratios and different feeding strategies(batch andfed-batch).It was discovered that the rheology of xanthan fermentation broth is of paramountimportance to the above characteristics.The aerated power consumption and power number are both afunction of aeration rate during the initial stage of the fermentation when the viscosity is low andthe Reynolds number high.However when the becames viscous and Reynolds unmber≤10~3,thegas velocity does not show any effect on the power number.The oxygen mass transfer coefficientsand the overall heat transfer coefficients are both dependent on the impeller speed,the apparentviscosity of the broth and the D/T ratio.These data taken from practical 展开更多
关键词 XANTHAN FERMENTATION RHEOLOGY power consumption mass transfer heat transfer
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Numerical Simulation of Three-dimensional Heat and Mass Transfer in Spray Cooling of Converter Gas in a Venturi Scrubber 被引量:3
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作者 LU Tao WANG Kuisheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期745-754,共10页
In order to predict the pressure drop, collection efficiency, velocity, temperature and mole fraction of vapor in an industrial venturi scrubber with water spraying for converter gas cooling, a three-dimensional model... In order to predict the pressure drop, collection efficiency, velocity, temperature and mole fraction of vapor in an industrial venturi scrubber with water spraying for converter gas cooling, a three-dimensional model of heat and mass transfer with phase change is established. The gas flow and liquid droplets are treated as a continuous phase with a Eulerian approach and as a discrete phase with a Lagrangian approach, respectively. The coupled problem of heat, force, and mass transfers between gas flow and liquid droplets is solved by a commercial computational fluid dynamics(CFD) package, FLUENT. The numerical results show that the water injections have an important influence on the distributions of pressure, velocity, temperature, and mole fraction of vapor, especially for the spraying region in the throat. In the spraying region, the pressure drop is higher and the velocity is lower than in other regions due to the gas-droplet drag, while the temperature is lower because the droplet absorbs large amounts of heat from the high temperature gas and the mole fraction of vapor is higher due to the phase change of the liquid droplet. A number of cases with different Water-to-gas volume flow ratios and baffle openings were simulated. The dependence of pressure drop, velocity, temperature, mole fraction of vapor, and collection efficiency on both the water-to-gas volume flow ratio and baffle opening are analyzed. The good agreements between simulation results and experiment data of pressure drop, temperature, and collection efficiency validate the model. The model should facilitate optimization of the venturi scrubber design in order to give better performance with lower pressure drops and higher collection efficiency. 展开更多
关键词 numerical simulation heat and mass transfer spray cooling converter gas venturi scrubber
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A review on metal additive manufacturing:modeling and application of numerical simulation for heat and mass transfer and microstructure evolution 被引量:4
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作者 Chuan-ming Liu Hua-bing Gao +3 位作者 Li-yu Li Jian-dong Wang Chun-huan Guo Feng-chun Jiang 《China Foundry》 SCIE CAS 2021年第4期317-334,共18页
Metal additive manufacturing technology has been widely used in prototyping,parts manufacturing and repairing.Metal additive manufacturing is a multi-scale and multi-physical coupling process with complex physical phe... Metal additive manufacturing technology has been widely used in prototyping,parts manufacturing and repairing.Metal additive manufacturing is a multi-scale and multi-physical coupling process with complex physical phenomena of heat and mass transfer and microstructure evolution.It is hard to directly observe the dynamic behavior and microstructure evolution of molten pool during additive manufacturing.Therefore,numerical simulation of additive manufacturing process is significant since it can efficiently and pertinently predict and analyze the physical phenomena in the process of metal additive manufacturing,and provide a reference for technological parameters selection.In this review,the research progress of numerical simulation of metal additive manufacturing is discussed.Various aspects of numerical simulation models are reviewed,including:(1)Introduction of basic control method and physical description of numerical simulation models;(2)Comparison of various heat and mass transfer models based on different physical assumptions(heat conduction model;heat flux coupling model;discrete powder particle heat flux coupling model);(3)Applications of various microstructure evolution models[phase field(PF),cellular automata(CA),and Monte Carlo(MC)].Finally,the development trend of numerical simulation of metal additive manufacturing,including the thermal-flow-solid coupling model and deep learning for numerical model,is analyzed. 展开更多
关键词 additive manufacturing numerical simulation heat and mass transfer microstructure evolution
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Simultaneous effects of chemical reaction and Ohmic heating with heat and mass transfer over a stretching surface: A numerical study 被引量:2
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作者 S.R.Mishra M.M.Bhatti 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第9期1137-1142,共6页
In this article, we have considered the simultaneous influence of ohmic heating and chemical reaction on heat and mass transfer over a stretching sheet. The effects of applied magnetic field are also taken into consid... In this article, we have considered the simultaneous influence of ohmic heating and chemical reaction on heat and mass transfer over a stretching sheet. The effects of applied magnetic field are also taken into consideration while the induced magnetic field is not considered due to very small magnetics Reynolds number. The governing flow problem comprises of momentum, continuity, thermal energy and concentration equation which are transformed into highly nonlinear coupled ordinary differential equations by means of similarity transforms, which are then, solved numerically with the help of Successive Linearization method(SLM) and Chebyshev Spectral collocation method. Numerical values of skin friction coefficient, local Nusselt number, and Sherwood number are also taken into account with the help of tables. The physical influence of the involved parameters of flow velocity, temperature and concentration distribution is discussed and demonstrated graphically. The numerical comparison is also presented with the existing published results and found that the present results are in excellent agreement which also confirms the validity of the present methodology. 展开更多
关键词 Ohmic heating heat and mass transfer Chemical reaction Successive linearization method
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Laminar Forced Convection Heat and Mass Transfer of Humid Air across a Vertical Plate with Condensation 被引量:3
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作者 李成 李俊明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期944-954,共11页
Condensation of humid air along a vertical plate was numerically investigated, with the mathematical model built on the full boundary layer equations and the film-wise condensation assumption. The velocity, heat and m... Condensation of humid air along a vertical plate was numerically investigated, with the mathematical model built on the full boundary layer equations and the film-wise condensation assumption. The velocity, heat and mass transfer characteristics at the gas-liquid interface were numerical analyzed and the results indicated that it was not reasonable to neglect the condensate film from the point of its thickness only. The condensate film thickness, interface temperature drop and the interface tangential velocity affect the physical fields weakly. However, the subcooling and the interface normal velocity were important factors to be considered before the simplification was made. For higher wall temperature, the advective mass transfer contributed much to the total mass transfer. Therefore, the boundary conditions were the key to judge the rationality of neglecting the condensate film for numerical solutions. The numerical results were checked by comparing with experiments and correlations. 展开更多
关键词 CONDENSATION binary mixture convective heat and mass transfer
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Simulation of Heat and Mass Transfer in a Grain Pile on the Basis of a 2D Irregular Pore Network 被引量:3
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作者 Pengxiao Chen Kai Huang +3 位作者 Fenghe Wang Weijun Xie Shuo Wei Deyong Yang 《Fluid Dynamics & Materials Processing》 EI 2019年第4期367-389,共23页
The so-called pore network model has great advantages in describing the process of heat and mass transfer in porous media.In order to construct a random two-dimensional(2D)irregular pore network model for an unconsoli... The so-called pore network model has great advantages in describing the process of heat and mass transfer in porous media.In order to construct a random two-dimensional(2D)irregular pore network model for an unconsolidated material,image processing technology was used to extract the required topological and geometric information from a 2D sample of soybean particles,and a dedicated algorithm was elaborated to merge some adjacent small pores.Based on the extracted information,a 2D pore network model including particle information was reconstructed and verified to reflect the pore structure of discrete particles.This method was used to reconstruct a random 2D irregular pore network model of wheat.Accordingly,a multi-scale heat and mass transfer model was implemented to simulate the drying of wheat.The simulation results were consistent with the experimental results,which indicates that the reconstructed irregular pore network model can effectively simulate the real pore structure inside unconsolidated porous media.The present approach may be regarded as the foundation for establishing in the future a three-dimensional pore network model and studying the heat and mass transfer process in a grain pile. 展开更多
关键词 MATLAB pore network heat and mass transfer thiessen polygon
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Mixed convective heat and mass transfer analysis for peristaltic transport in an asymmetric channel with Soret and Dufour effects 被引量:5
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作者 F.M.Abbasi A.Alsaedi T.Hayat 《Journal of Central South University》 SCIE EI CAS 2014年第12期4585-4591,共7页
The present investigation addresses the simultaneous effects of heat and mass transfer in the mixed convection peristaltic flow of viscous fluid in an asymmetric channel. The channel walls exhibit the convective bound... The present investigation addresses the simultaneous effects of heat and mass transfer in the mixed convection peristaltic flow of viscous fluid in an asymmetric channel. The channel walls exhibit the convective boundary conditions. In addition, the effects due to Soret and Dufour are taken into consideration. Resulting problems are solved for the series solutions. Numerical values of heat and mass transfer rates are displayed and studied. Results indicate that the concentration and temperature of the fluid increase whereas the mass transfer rate at the wall decreases with increase of the mass transfer Biot number. Furthermore, it is observed that the temperature decreases with the increase of the heat transfer Biot number. 展开更多
关键词 peristaltic transport heat and mass transfer Soret and Dufour effects convective boundary conditions
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Effects of Combined Heat and Mass Transfer on Entropy Generation due to MHD Nanofluid Flow over a Rotating Frame 被引量:1
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作者 F.Mabood T.A.Yusuf +2 位作者 A.M.Rashad W.A.Khan Hossam A.Nabwey 《Computers, Materials & Continua》 SCIE EI 2021年第1期575-587,共13页
The current investigation aims to explore the combined effects of heat and mass transfer on free convection of Sodium alginate-Fe_(3)O_(4) based Brinkmann type nanofluid flow over a vertical rotating frame.The Tiwari ... The current investigation aims to explore the combined effects of heat and mass transfer on free convection of Sodium alginate-Fe_(3)O_(4) based Brinkmann type nanofluid flow over a vertical rotating frame.The Tiwari and Das nanofluid model is employed to examine the effects of dimensionless numbers,including Grashof,Eckert,and Schmidt numbers and governing parameters like solid volume fraction of nanoparticles,Hall current,magnetic field,viscous dissipation,and the chemical reaction on the physical quantities.The dimensionless nonlinear partial differential equations are solved using a finite difference method known as Runge-Kutta Fehlberg(RKF-45)method.The variation of dimensionless velocity,temperature,concentration,skin friction,heat,and mass transfer rate,as well as for entropy generation and Bejan number with governing parameters,are presented graphically and are provided in tabular form.The results reveal that the Nusselt number increases with an increase in the solid volume fraction of nanoparticles.Furthermore,the rate of entropy generation and Bejan number depends upon the magnetic field and the Eckert number. 展开更多
关键词 Nanofluid flow entropy generation heat and mass transfer viscous dissipation chemical reaction
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An Unsteady Oscillatory Flow of Generalized Casson Fluid with Heat and Mass Transfer:A Comparative Fractional Model 被引量:1
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作者 Anis ur Rehman Farhad Ali +3 位作者 Aamina Aamina Anees Imitaz Ilyas Khan Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2021年第2期1445-1459,共15页
It is of high interest to study laminar flow with mass and heat transfer phenomena that occur in a viscoelastic fluid taken over a vertical plate due to its importance in many technological processes and its increased... It is of high interest to study laminar flow with mass and heat transfer phenomena that occur in a viscoelastic fluid taken over a vertical plate due to its importance in many technological processes and its increased industrial applications.Because of its wide range of applications,this study aims at evaluating the solutions corresponding to Casson fluids’oscillating flow using fractional-derivatives.As it has a combined mass-heat transfer effect,we considered the fluid flow upon an oscillatory infinite vertical-plate.Furthermore,we used two new fractional approaches of fractional derivatives,named AB(Atangana–Baleanu)and CF(Caputo–Fabrizio),on dimensionless governing equations and then we compared their results.The Laplace transformation technique is used to get the most accurate solutions of oscillating motion of any generalized Casson fluid because of the Cosine oscillation passed over the infinite vertical-plate.We obtained and analyzed the distribution of concentration,expressions for the velocity-field and the temperature graphically,using various parameters of interest.We also analyzed the Nusselt number and the skin friction due to their important engineering usage. 展开更多
关键词 AB and CF fractional derivatives generalized Casson fluid heat and mass transfer OSCILLATION
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Thermal Diffusion Effect on MHD Heat and Mass Transfer Flow past a Semi Infinite Moving Vertical Porous Plate with Heat Generation and Chemical Reaction 被引量:1
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作者 Gurivireddy P. Raju M. C. +1 位作者 Mamatha B. Varma S. V. K. 《Applied Mathematics》 2016年第7期638-649,共12页
The objective of present work is to study the thermo diffusion effect on an unsteady simultaneous convective heat and mass transfer flow of an incompressible, electrically conducting, heat generating/absorbing fluid a... The objective of present work is to study the thermo diffusion effect on an unsteady simultaneous convective heat and mass transfer flow of an incompressible, electrically conducting, heat generating/absorbing fluid along a semi-infinite moving porous plate embedded in a porous medium with the presence of pressure gradient, thermal radiation field and chemical reaction. It is assumed that the permeable plate is embedded in a uniform porous medium and moves with a constant velocity in the flow direction in the presence of a transverse magnetic field. It is also assumed that the free stream consists of a mean velocity, temperature and concentration over which are super imposed an exponentially varying with time. The equations of continuity, momentum, energy and diffusion, which govern the flow field, are solved by using a regular perturbation method. The behavior of the velocity, temperature, concentration, Skin-friction, rate of heat transfer and rate of mass transfer has been discussed for variations in the physical parameters. An increase in both Pr and R results a decrease in thermal boundary layer thickness. However, concentration decreases as Kr, Sc increase but it increases with an increase in both So and δ. 展开更多
关键词 heat Generation/Absorption Chemical Reaction MHD Thermal Radiation Thermal Diffusion heat and mass transfer Semi-Infinite Vertical Plate
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Heat and Mass Transfer in MHD Visco-Elastic Fluid Flow through a Porous Medium over a Stretching Sheet with Chemical Reaction 被引量:5
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作者 Saleh M. Alharbi Mohamed A. A. Bazid Mahmoud S. El Gendy 《Applied Mathematics》 2010年第6期446-455,共10页
This paper presents the study of convective heat and mass transfer characteristics of an incompressible MHD visco-elastic fluid flow immersed in a porous medium over a stretching sheet with chemical reaction and therm... This paper presents the study of convective heat and mass transfer characteristics of an incompressible MHD visco-elastic fluid flow immersed in a porous medium over a stretching sheet with chemical reaction and thermal stratification effects. The resultant governing boundary layer equations are highly non-linear and coupled form of partial differential equations, and they have been solved by using fourth order Runge-Kutta integration scheme with Newton Raphson shooting method. Numerical computations are carried out for the non-dimensional physical parameters. Here a numerical has been carried out to study the effect of different physical parameters such as visco-elasticity, permeability of the porous medium, magnetic field, Grashof number, Schmidt number, heat source parameter and chemical reaction parameter on the flow, heat and mass transfer characteristics. 展开更多
关键词 heat and mass transfer INCOMPRESSIBLE MHD VISCO-ELASTIC POROUS MEDIUM Chemical Reaction
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A Cell Model to Describe and Optimize Heat and Mass Transfer in Contact Heat Exchangers 被引量:2
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作者 Vadim Mizonov Nickolay Yelin Piotr Yakimychev 《Energy and Power Engineering》 2011年第2期144-149,共6页
A cell model to describe and optimize heat and mass transfer in contact heat exchangers for utilization of exhaust gases heat is proposed. The model is based on the theory of Markov chains and allows calculating heat ... A cell model to describe and optimize heat and mass transfer in contact heat exchangers for utilization of exhaust gases heat is proposed. The model is based on the theory of Markov chains and allows calculating heat and mass transfer at local moving force of the processes in each cell. The total process is presented as two parallel chains of cells (one for water flow and one for gas flow). The corresponding cells of the chains can exchange heat and mass, and water and gas can travel along their chains according to their transition ma-trices. The results of numerical experiments showed that the most part of heat transfer occurs due to moisture condensation from gas and the most intense heat transfer goes near the inlet of gas. Experimental validation of the model showed a good correlation between calculated and experimental data for an industrial contact heat exchanger if appropriate empirical equations were used to calculate heat and mass transfer coefficient. It was also shown that there exists the optimum height of heat exchanger that gave the maximum gain in heat energy utilization. 展开更多
关键词 Direct CONTACT heat EXCHANGER heat and mass transfer CONDENSATION State VECTOR Transition Matrix Optimization
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Geologic-Geophysical Indicators of the Deep Structure of Zones of Geothermal Anomalies for Allocation of Channels of the Deep Heat and Mass Transfer 被引量:4
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作者 R. A. Umurzakov H. A. Abidov G. Yu. Yuldashev 《Open Journal of Geology》 2017年第9期1452-1463,共12页
On the basis of the analysis of field thermogeochemical data along abnormal zones of a thermal stream in the Bukhara-Khiva, oil-and-gas region of the Turan (Tegermen, Chagakul, Shimoly Alat, Beshtepa) was succeeded to... On the basis of the analysis of field thermogeochemical data along abnormal zones of a thermal stream in the Bukhara-Khiva, oil-and-gas region of the Turan (Tegermen, Chagakul, Shimoly Alat, Beshtepa) was succeeded to obtain important data on a deep structure of sites. Data of gas-chemical and geothermal observations show about confinedness of abnormal concentration of methane to zones of the increased values of the temperature field the measured values of temperatures (Tegermen Square and others). On geoelectric section mines 2-D of inversion of the MT-field depth of 4000 m are lower, among very high-resistance the chemogenic and carbonate deposits of the Paleozoic is traced the subvertical carrying-out abnormal zone. This zone is identified as the channel of a deep heat and mass transfer with which hydrocarbon (HC) deposits are connected. It is shown that electro-investigation when using a geophysical complex can and has to become “advancing” at exploration by oil and gas. 展开更多
关键词 Anomaly of the Thermal Field Thermogeochemical Data JUVENILE Gases Channel heat and mass transfer DEEP Structure GEOELECTRIC Section Deposits of Oil and Gas
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Finite element solution of heat and mass transfer flow with Hall current,heat source,and viscous dissipation
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作者 S.SIVAIAH R.SRINIVASA-RAJU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第5期559-570,共12页
The aim of the paper is to investigate the effect of heat and mass transfer on the unsteady magnetohydrodynamic free convective flow with Hall current, heat source, and viscous dissipation. The problem is governed by ... The aim of the paper is to investigate the effect of heat and mass transfer on the unsteady magnetohydrodynamic free convective flow with Hall current, heat source, and viscous dissipation. The problem is governed by the system of coupled non-linear partial differential equations whose exact solution is difficult to obtain. Therefore, the problem is solved by using the Galerkin finite element method. The effects of the various parameters like Hall current, Eckert number, heat source parameter, Prandtl number, and Schmidt number on the velocity components, the temperature, and the concentration are also examined through graphs. 展开更多
关键词 heat and mass transfer Hall current viscous dissipation heat generation
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