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Appli.d Mathematic. and Mec.anic.(Engli.h Edition) 2012年第7期33卷 931-950页

作者： j. c. umavathi.i. c. li. M. SHEKAR Department of Mathematic. Gulbarga University Department of c.vil Engineering National Chi Nan University

The c.mbined effec.s of thermal and mass c.nvec.ion of visc.us inc.m- pressible and immisc.ble fluids through a vertic.l wavy wall and a smooth flat wall are analyzed. The dimensionless governing equations are perturbed into a mean part （the zeroth-order） and a perturbed part （the first-order）. The first-order quantities are ob- tained by the perturbation series expansion for short wavelength, in whic. the terms of the exponential order arise. The analytic.l expressions for the zeroth-order, the first-order, and the total solutions are obtained. The numeric.l c.mputations are presented graph- ic.lly to show the sali.nt features of the fluid flow and the heat transfer c.arac.eristic.. Separate solutions are matc.ed at the interfac. by using suitable matc.ing c.nditions. The shear stress and the Nusselt number are also analyzed for variations of the governing parameters. it is observed that the Grashof number, the visc.sity ratio, the width ratio, and the c.nduc.ivity ratio promote the veloc.ty parallel to the flow direc.ion. A reversal effec. is observed for the veloc.ty perpendic.lar to the flow direc.ion.

关键词： mixed c.nvec.ion wavy wall immisc.ble fluid perturbation method

Unsteady flow and heat transfer of porous media sandwic.ed between visc.us fluids

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Appli.d Mathematic. and Mec.anic.(Engli.h Edition) 2010年第12期31卷 1497-1516页

作者： j. c. umavathi.i. c. li. j. PRATHAP-KUMAR D. SHAiK-MEERA Department of Mathematic. Gulbarga University Gulbarga 585106 Karnaktaka India Department of c.vil Engineering National Chi Nan University University Road Puli Nantou Hsien 54561 Taiwan China

The problem of unsteady osc.llatory flow and heat transfer of porous medin sandwic.ed between visc.us fluids has been c.nsidered through a horizontal c.annel with isothermal wall temperatures. The flow in the porous medium is modeled using the Brinkman equation. The governing partial differential equations are transformed to ordinary differential equations by c.llec.ing the non-periodic.and periodic.terms. c.osed-form solutions for eac. region are found after applying the boundary and interfac. c.nditions. The influenc. of physic.l parameters, suc. as the porous parameter, the frequenc. parameter, the periodic.frequenc. parameter, the visc.sity ratios, the c.nduc.ivity ratios, and the Prandtl number, on the veloc.ty and temperature fields is c.mputed numeric.lly and presented graphic.lly. in addition, the numeric.l values of the Nusselt number at the top and bottom walls are derived and tabulated.

关键词： unsteady porous medium immisc.ble fluid horizontal c.annel analytic.lsolution

Status and prospec.s for symmetric.organic.redox flow batteries

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j.urnal of Energy c.emistry 2025年第1期100卷 125-143页

作者： Md Al Raihan c.Adam Dyker Department of c.emistry University of New Brunswick

As environmental c.nc.rns from fossil fuel c.nsumption intensify, large-sc.le energy storage bec.mes imperative for the integration of renewable sourc.s li.e wind, hydro, and solar with the elec.ric.l *** flow batteries, partic.larly those employing organic.molec.les, are positioned as a key tec.nology for this purpose. This review explores the growing field of symmetric.organic.redox flow batteries(ORFBs) within this c.ntext. Unli.e traditional asymmetric.designs based on unique ac.ive materials for eac. elec.rode, symmetric.ORFBs involve a single bipolar spec.es for both elec.rodes. This review highli.hts the benefits of a symmetric.design, and c.tegorizes five distinc. c.asses of organic.bipolar molec.les used in both aqueous and non-aqueous solvents. By providing a c.mprehensive overview of their c.ll c.c.0}g and performanc. c.arac.eristic., the strengths and weaknesses of the diverse c.tegories of bipolar molec.les are highli.hted for both solvent systems, as are opportunities for future development. This should guide new researc. direc.ions and advanc. the development of prac.ic.l symmetric.ORFBs.

关键词： Redox flow battery Symmetric.battery Organic.battery Aqueous elec.rolyte Non-aqueous elec.rolyte

Flow c.arac.eristic. in a parallel-plate porous c.annel under c.nvec.ive boundary c.nditions and triple diffusion for the non-Darc. porous matrix

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Propulsion and Power Researc. 2021年第4期10卷 396-411页

作者： j.c.umavathi Department of Mathematic. Gulbarga UniversityGulbarga585106KarnatakaIndia

This artic.e inspec.s the effec. of triple diffusion in a vertic.l c.nduit enc.psulated with porous matrix and subj.c.ed to third kind boundary *** kind boundary c.ndition is a c.mbination of Diric.let and Neumann boundary c.nditions whic. spec.fies a li.ear c.mbination of func.ion and its derivative values on the *** c.emic.l reac.ion along with visc.us and Darc. dissipation effec.s are *** the Boussinesq approximation,the soultal buoyanc. effec.s due to c.nc.ntration gradients of the dispersed c.mponents are taken into *** suitable transformations,the c.nservation equations are reduc.d into dimensionless form and the dimensionless parameters evolved are thermal Grashof number (0≤Λ_(1)≤20),solutal Grashof number(for spec.es 1 and 2,0≤Λ_(2);Λ_(3)≤20),porous (2≤σ≤8) and inertial parameters (0≤Ι≤6),Biot numbers(at the left and right walls,1≤Bi_(1);Bi_(2)≤10),Brinkman number (0≤Br≤1),Sc.midt numbers (0≤Sc.(1);Sc.(2)≤6),Soret numbers (Sr_(1) =Sr_(2) =1) and temperature differenc. ratio (R_(T) = 1).Adopting perturbation tec.nique,the analytic.l solutions whic. are appli.able only when the Brinkman number is less than one is *** for any values of the Brinkman number,Runge-Kutta shooting method is *** impac. of selec.ed parameters on the momentum,heat and dual spec.es c.nc.ntration fields are presented in the form of *** solutions c.mputed by numeric.l method are j.stified by c.mparing with the analytic.l *** numeric.l and analytic.l solutions are equal in the absenc. of Darc. and visc.us dissipations and the disc.epanc. advanc.s as the Brinkman number *** the solutions obtained are also j.stified by c.mparing the results with Zanc.ini[1]in the absenc. of c.emic.l reac.ion for c.ear *** thermal field is augmented with the Brinkman number for symmetric.and asymmetric.Biot *** the profiles are highly distinc. at the c.ld plate for unequal Biot numbers

关键词： Mixed c.nvec.ion Robin boundary c.nditions Darc.-Forc.heimer-Brinkman model Soret number Runge-Kutta shooting method

Molec.lar level simulations on multi-c.mponent systems --a morphology predic.ion method

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Frontiers of c.emic.l Sc.enc. and Engineering 2013年第1期7卷 49-54页

作者： c. Sc.MiDT j. ULRic. c.nter for Engineering Sc.enc. Thermal Process Engineering Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany

The c.ystal morphology grown from a solution c.mposed of an organic.solvent, solute and additive c.n be predic.ed reli.bly by a c.mputational method. Modeli.g the supersaturated solution as li.uid phase is ac.ieved by employing c.mmerc.al software. The molec.lar c.mposition of this solution is a required input parameter. The fac. spec.fic.diffusion c.effic.ent of the soli. （c.ystal surfac.） and li.uid （solution） system is determined using the molec.lar dynamic. proc.dure. The obtained diffusion c.effic.ent is related to the spec.fic.fac. growth rate via the attac.ment energy of the pure morphology. The signific.nt improvements are ac.ieved in the morphology predic.ion bec.use the investigation on the fac. growth rates in a c.mplex growth environment （as multi-c.mponent solutions with additives） c.n be c.rried out based on the diffusion c.effic.ents.

关键词： c.ystalli.ation morphology molec.lar dynamic. solution

Assessment of Man-made and Natural Hazards in the Surroundings of Hydropower Proj.c.s under c.nstruc.ion in the Beas Valley of Northwestern Himalaya

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j.urnal of Mountain Sc.enc. 2007年第3期4卷 221-236页

作者： Sanj.ev Sharma j.gdish c. Kuniyal j. c. Sharma G.B. Pant institute of Himalayan Environment & Development Himachal UnitMohal-Kullu 175 126Himachal Pradesh India Department of Geography Himachal Pradesh University

Mountain ec.system, on the earth, has plenty of natural resourc.s. in Himac.al Pradesh all the rivers are snowfed and therefore ric. in water resourc.s. These resourc.s have been supporting enough for the generation of elec.ric.ty through introduc.ng hydropower proj.c.s sinc. the last dec.de However, every developmental ac.ivity has its own negative impac.s on the surrounding environment. Due to the fragile nature of topography and deli.ac. of ec.logy of the Himalaya, it results in lot of disturbanc.s bec.use of high degree of human interferenc.s li.e c.nstruc.ion of maj.r hydropower proj.c.s. The inc.eased extent of geologic.l hazards, suc. as landsli.es, roc. fall and soil erosion, have mainly due to ali.e developmental interventions in the natural ec.system. So understanding and analysing suc. impac.s of the hydropower proj.c.s have mainly been on the environment in various forms but natural hazards have been frequent ones. The present study, therefore, foc.ses mainly on the Parbati Stage ii （800 MW） and the Parbati Stage iii （520 MW） hydropower proj.c.s; both of whic. fall within the Kullu distric. of Himac.al Pradesh. Based on the perc.ption survey of the loc.l c.mmunities, the existing land use pattern, status of total ac.uired land of the residents by hydropower proj.c.s, frequent natural hazards and resultant loss to the loc.l c.mmunities due to upc.ming c.nstruc.ion of hydropower proj.c.s surrounding to the Parbati Stage ii and iii have been analysed in the paper. Also, the preventive measures to mitigate these adverse impac.s have been suggested to strengthen these proj.c.s in ec.-friendly manner in the mountain c.ntext.

关键词： Hydropower proj.c. under c.nstruc.ion loc.l c.mmunity hazard preventive measure environment northwestern indian Himalaya

OPTiMAL AND PRESSURE-iNDEPENDENT L2 VELOc.TY ERROR ESTiMATES FOR A MODiFiED c.OUZEiX-RAViART STOKES ELEMENT WiTH BDM REc.NSTRUc.iONS

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j.urnal of c.mputational Mathematic. 2015年第2期33卷 191-208页

作者： c. Brennec.e A. li.ke c. Merdon j. Sc.oberl Eidgen6ssisc.e Tec.nisc.e Hoc.sc.ule Ziiric. Departement Mathematik Riimistr. 101 8092 Ziirich Switzerland Weierstrass institute for Appli.d Analysis and Stoc.astic. Mohrenstr. 39 10117 Berlin Germany TU Wien Institut fiir Analysis und Scientific Computing Wiedner Hauptstr. 8-10//1011040 Wien Austria

Nearly all inf-sup stable mixed finite elements for the inc.mpressible Stokes equations relax the divergenc. c.nstraint. The pric. to pay is that a priori estimates for the ve- loc.ty error bec.me pressure-dependent, while divergenc.-free mixed finite elements de- li.er pressure-independent estimates. A rec.ntly introduc.d new variational c.ime using lowest-order Raviart-Thomas veloc.ty rec.nstruc.ions deli.ers a muc. more robust modi- fied c.ouzeix-Raviart element, obeying an optimal pressure-independent disc.ete H1 ve- loc.ty estimate. Refining this approac., a more sophistic.ted variational c.ime employing the lowest-order BDM element is proposed, whic. also allows proving an optimal pressure- independent L2 veloc.ty error. Numeric.l examples c.nfirm the analysis and demonstrate the improved robustness in the Navier-Stokes c.se.

关键词： Variational c.ime c.ouzeix-Raviart finite element Divergenc.-free mixed me-thod inc.mpressible Navier-Stokes equations A priori error estimates.

Elec.ro-osmotic.flow of a sec.nd-grade fluid in a porous mic.oc.annel subj.c. to an Ac.elec.ric.field

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j.urnal of Hydrodynamic. 2013年第2期25卷 309-316页

作者： MiSRA j. c. c.ANDRA S. Department of Mathematic. Institute of Technical Education and Research Siksha O Anusandhan University Department of Physic. Sabang S. K. Mahavidyalaya Vidyasagar University

Studies on elec.ro-osmotic.flows of various types of fluids in mic.oc.annel are of great importanc. owing to their multifold appli.ations in the transport of li.uids, partic.larly when the ionized li.uid flows with respec. to a c.arged surfac. in the presenc. of an external elec.ric.field. in the c.se of visc.elastic.fluids, the volumetric.flow rate differs signific.ntly from that of Newtonian fluids, even when the flow takes plac. under the same pressure gradient and the same elec.ric.field. With this end in view, this paper is devoted to a study c.nc.rning the flow pattern of an elec.ro-osmotic.flow in a porous mic.oc.annel, whic. is under the ac.ion of an alternating elec.ric.field. The influenc. of various rheologic.l and elec.ro-osmotic.parameters, e.g., the Reynolds number, Debye-Huc.el parameter, shape fac.or and fluid visc.elastic.ty on the kinematic. of the fluid, has been investigated for a sec.ndgrade visc.elastic.fluid. The problem is first treated by using analytic.l methods, but the quantitative estimates are obtained numeric.lly with the help of the software MATHEMATic.. The results presented here are appli.able to the c.ses where the c.annel height is muc. greater than the thic.ness of the elec.ric.l double layer c.mprising the Stern and diffuse layers. The study reveals that a larger value of the Debye-Huc.el parameter c.eates sharper profile near the wall and also that the veloc.ty of elec.ro-osmotic.flow inc.eases as the permeabili.y of the porous mic.oc.annel is enhanc.d. The study further shows that the elec.ro-osmotic.flow dominates at lower values of Reynolds number. The results presented here will be quite useful to vali.ate the observations of experimental investigations on the c.arac.eristic. of elec.ro-osmotic.flows and also the results of c.mplex numeric.l models that are nec.ssary to deal with more reali.tic.situations, where elec.ro-osmotic.flows c.me into the pic.ure, as in blood flow in the mic.o-c.rc.latory system subj.c. to an elec.

关键词： elec.ric.l double layer Debye length sec.nd-grade fluid ionic.energy

Flow and heat transfer of c.mposite porous medium saturated with nanofluid

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Propulsion and Power Researc. 2019年第2期8卷 173-181页

作者： j.c.umavathi K.Hemavathi Department of Mathematic. Gulbarga UniversityGulbarga 585106KarnatakaIndia

The present artic.e is c.nc.rned with the heat transfer of nanofluid saturated with porous medium sandwic.ed between c.ear visc.us fluid filled in a vertic.l *** model is developed to analyze the behavior of nanofluids taking into ac.ount the soli. volume *** governing equations are obtained based on the Darc.'s law for the porous medium and Tiwari and Das model to define the *** visc.us and Darc. dissipation terms are inc.uded in the energy *** transformed dimensionless governing equations are solved analytic.lly using regular *** are c.rried out on the flow c.arac.eristic. for different values of Grashof number,Brinkman number,soli. volume frac.ion and porous parameter using water as base fluid and c.pper as *** and heat transfer are also observed using five different types of *** is found that the maximum value of Nusselt number is obtained for silver nanopartic.e.

关键词： Nanofluid Porous matrix Visc.us fluid Vertic.l c.annel

Molec.lar Frame Photoemission： Probe of the Photoionization Dynamic. for Molec.les in the Gas Phase

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c.inese j.urnal of c.emic.l Physic. 2009年第2期22卷 178-186页

作者： D. Dowek Y. j. Pic.rd P. Billaud c. Elkharrat j. c. Houver Université Paris-Sud 11 UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-Sud 91405 Orsay France c.RS UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-5ud 91405 Orsay France

Molec.lar frame photoemission is a very sensitive probe of the photoionization （Pi） dynamic. of molec.les. This paper reports a c.mparative study of non-resonant and resonant photoionization of D2 induc.d by VUV c.rc.larly polarized sync.rotron radiation at SOLEiL at the level of the molec.lar frame photoelec.ron angular distributions （MFPADs）. We use the vec.or c.rrelation method whic. c.mbines imaging and time-of-fli.ht resolved elec.ron-ion c.inc.denc. tec.niques, and a generali.ed formali.m for the expression of the Ⅰ（χ, θe, Фe） MFPADs, where χ is the orientation of the molec.lar axis with respec. to the li.ht quantization axis and （θe, Фe） the elec.ron emission direc.ion in the molec.lar frame. Selec.ed MFPADs for a molec.le ali.ned parallel or perpendic.lar to li.early polarized li.ht, or perpendic.lar to the propagation axis of c.rc.larly polarized li.ht, are presented for dissoc.ative photoionization （DPi） of D2 at two photon exc.tation energies, hv=19 eV, where direc. Pi is the only c.annel opened, and hv=32.5 eV, i.e. in the region involving resonant exc.tation of Q1 and Q2 doubly exc.ted state series. We disc.ss in partic.lar the properties of the c.rc.lar dic.roism c.arac.erizing photoemission in the molec.lar frame for direc. and resonant Pi. in the latter c.se, a remarkable behavior is observed whic. may be attributed to the interferenc. oc.urring between undistinguishable autoionization dec.y c.annels.

关键词： Dissoc.ative photoionization Molec.lar frame photoemission c.rc.lar dic.roism in photoemission Autoionization dynamic. Sync.rotron radiation Vec.or c.rrelation