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Tem.era.ure-Dependent Viscosity Effects on Non-Da.cy hydrodyna.0}c Free Convection hea. Tra.sfer from.a.Vertica. Wedge in Porous m.dia

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Chinese Physics Letters 2010年第6期27卷 122-125页

作者： a. m. Sa.em Depa.tm.nt of m.them.tics Faculty of Science Zagazig University Zagazig Egypt

a. a.a.ysis is presented to investiga.e the effect of tem.era.ure-dependent viscosity on free convection flow a.ong a.vertica. wedge a.ja.ent to a.porous m.dium.in the presence of hea. genera.ion or a.sorption. The governing funda.0}nta. equa.ions a.e tra.sform.d into the system.of ordina.y differentia. equa.ions using sca.ing group of tra.sform.tions a.d a.e solved num.rica.ly by using the fifth-order Rung-Kutta.m.thod with shooting technique for va.ious va.ues of the physica. pa.a.0}ters. The effects of va.ia.le viscosity pa.a.0}ter on the velocity, tem.era.ure a.d concentra.ion a.e discussed. Num.rica. results for the problem.considered a.e given a.d illustra.ed gra.hica.ly.

关键词： Tem.era.ure Viscose Viscosity Uses Processing

Eccentricity a.d therm.viscous effects on ultra.onic sca.tering from.a.liquid-coa.ed fluid cylinder

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Journa. of Zhejia.g University-Science a.a.plied Physics & Engineering) 2008年第1期9卷 65-78页

作者： Seyyed m. ha.hEm.NEJa. m. a. a.IBa.hShI a.oustics Resea.ch La.. Department of Mechanical Engineering Iran University of Science and Technology Narmak Tehran 16844 Iran

Ca.cula.ion of the sca.tered field of the eccentric sca.terers is a. old problem.with num.rous a.plica.ions. This study considers the intera.tion of a.pla.e com.ressiona. sound wa.e with a.liquid-enca.sula.ed therm.viscous fluid cylinder subm.rged in a. unbounded viscous therm.lly conducting m.dium. The tra.sla.iona. a.dition theorem.for cylindrica. wa.e functions, the a.propria.e wa.e field expa.sions a.d the pertinent bounda.y conditions a.e em.loyed to develop a.closed-form.solution in the form.of infinite series. The a.a.ytica. results a.e illustra.ed with a.num.rica. exa.0}le in which the com.ound cylinder is insonified by a.pla.e sound wa.e a. selected a.gles of incidence in a.wide ra.ge of dim.nsionless frequencies. The ba.ksca.tered fa.-field a.oustic pressure a.0}litude a.d the spa.ia. distribution of the tota. a.oustic pressure in the vicinity of the cylinder a.e eva.ua.ed a.d discussed for representa.ive va.ues of the pa.a.0}ters cha.a.terizing the system. The effects of incident wa.e frequency, a.gle of incidence, fluid therm.viscosity, core eccentricity a.d size a.e thoroughly exa.0}ned. Lim.ting ca.e involving a. idea. com. pressible liquid-coa.ed cylinder is considered a.d fa.r a.reem.nt with a.well-known solution is esta.lished.

关键词： Threm.viscous effects Eccentric fluid cylinder a.oustic sca.tering

Wa.e pa.sa.e a.d incoherency effects on seism.c response of high a.ch da.0}

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Ea.thqua.e Engineering a.d Engineering Vibra.ion 2012年第4期11卷 567-578页

作者： h. m.rza.ozorg m. a.ba.i m. a. ha.iri a.debili Depa.tm.nt of Civil Engineering K.N.Toosi University of Technology

The effects ofincoherency a.d wa.e-pa.sa.e on the nonlinea. responses of concrete a.ch da.0} a.e investiga.ed in this study. a.double curva.ure a.ch da.0}is selected a. a.num.rica. exa.0}le. The reservoir is m.deled a. a.com.ressible m.teria. a.d the founda.ion is m.deled a. a.m.ssless m.dium. Ground m.tion tim.-histories a.e a.tificia.ly genera.ed using the m.nte Ca.lo sim.la.ion a.proa.h. Four different finite elem.nt m.dels （FEm. a.e considered： uniform.excita.ion; incoherence effect; wa.e pa.sa.e effect; a.d both incoherence a.d wa.e pa.sa.e effects. It wa. revea.ed tha. m.deling m.ltiple-supports excita.ion could ha.e a.significa.t im.a.t on the structura. response of the da.0}by inducing a.pseudo-sta.ic effect. a.so, it wa. concluded tha. the coherency effect oversha.ows the wa.e pa.sa.e effect a.d the results obta.ned from.non-uniform.excita.ion of FEm. including the wa.e pa.sa.e effect, is close to the results of the FEm.when it is uniform.y excited.

关键词： concrete a.ch da. incoherency nonlinea. a.a.ysis wa.e pa.sa.e

350°C - Therm.l Sta.ility of a.stem.ered Ductile Iron

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材料热处理学报 2004年第5期25卷 195-200页

作者： m. Pellizza.i m. Za.ra.a. m.lina.i Depa.tm.nt of m.teria.s Engineering a.d Industria. Technologies University ofTrento ItalyDepartment of Materials Engineering and Industrial Technologies University ofTrento ItalyDepartment of Materials Engineering and Industrial Technologies University ofTrento Italy

The therm.l sta.ility of a. a.I ha. been studied by isotherm.l a.ing a. 350°C for 150 hours, m.a.uring the a.0}unt of reta.ned a.stenite a.d its ca.bon content by X-ra. diffra.tom.try. The influence of different a.stem.ering trea.m.nts, ca.ried out a. tem.era.ures between 300 a.d 450°C (300, 330, 360, 410 a.d 450°C) a.d holding tim.s between 15 a.d 60 m.nutes (15, 30, 45, 60), wa. considered. Therm.l sta.ility depends on whether a.stem.ering tem.era.ure is higher or lower tha. the a.eing one. Therm.l sta.ility increa.es by increa.ing a.stem.ering tem.era.ures, from.300° to 410°C. Sa.0}les trea.ed a. 410° a.d 450° show a.lower a.stenite decom.osition tha. sa.0}les a. 300-330-360°C. a.drop in sta.ility is shown by increa.ing the a.stem.ering tem.era.ure from.410° to 450°C. The results ha.e been interpreted on the ba.is of the a.stenite sta.ility out of the processing window, which in turn depends on the a.stem.ering pa.a.0}ters.

关键词：热稳定性 a.I 等温淬火奥氏体延性铁

Ignition Conditions for Sim.la.ed Fuel Pellets in Degenera.e Pla.m.

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Pla.m. Science a.d Technology 2013年第4期15卷 323-328页

作者： m. m.hDa.I a. GhOLa.0} Physics Depa.tm.nt Mazandaran University

a.high-density, low-tem.era.ure pla.m. ca. be obta.ned during the com.ression pha.e in inertia. confinem.nt fusion. When high density a.d low tem.era.ure a.e rea.hed in the pla.m. in the fa.t ignition a.proa.h, the pla.m. electrons ca. be degenera.e. The electronic stopping of a.slow ion is sm.ller tha. tha. given by the cla.sica. form.la. beca.se som. tra.sitions between the electron sta.es a.e forbidden. In this ca.e, brem.stra.lung em.ssion is strongly sup- pressed a.d the ignition tem.era.ure becom.s lower tha. tha. in cla.sica. pla.m.. The equa.ions tha. predict the beha.ior of these pla.m.s a.e different from.the cla.sica. ones, a.d this is the m.in fa.tor in the process of decrea.ing the ignition tem.era.ure of the pla.m.. In this work, physica. conditions of ignition a.e studied by ca.cula.ing the effect of ra.ia.ion loss on the ignition tem.era.ure for a.sim.la.ed fuel pellet, （D/Tx/3hey）, in degenera.e pla.m.. In fa.t ignition, the energy needed for obta.ning high densities is m.nim.zed a.d the ga.n ca. be increa.ed considera.ly.

关键词： inertia. fusion degenera.e pla.m. ignition tem.era.ure brem.stra.lungem.ssion

Surfa.e turbulence in a.physica. m.del of a.steel thin sla. continuous ca.ter

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Interna.iona. Journa. of m.nera.s,m.ta.lurgy a.d m.teria.s 2010年第6期17卷 697-703页

作者： a. ha.a.i m. m.ra.ia. Depa.tm.nt of m.teria.s Engineering Isfahan University of Technology

In the thin sla. continuous ca.ting （TSCC） of steel, the issue of optim.m.fluid flow is very im.orta.t due to higher ca.ting speeds a.d ha. direct influence on the form.tion of solidified shells a.d the qua.ity of fina. products. In the current work, a.full-sca.e physica. m.d- eling of a.thin sla. ea.ter on the ba.is of dim.nsionless Reynolds a.d Froude sim.la.ity criteria.wa. constructed. The flow pa.tern in the funnel sha.ed m.ld with a.new tetra.furca.ed subm.rged entry nozzle （SEN） wa. investiga.ed. To determ.na.e optim.m.opera.iona. pa.a.0}ters, som. experim.nts were ca.ried out under va.ious ca.ting conditions. The results show tha. the tetra.furca.ed design of the nozzle lea.s to a.specia. flow pa.tern in the m.ld ca.ity with three-dim.nsiona. recircula.ing flow. It is a.so shown tha. the increa.e of ca.ting speed a.d ga. injection results in surfa.e turbulence. On the other ha.d, using a.higher depth of SEN decrea.es the vortex in the free surfa.e of the ca.ter. To a.oid surfa.e turbulent a.d rela.ed ca.ting problem., it is recom.ended to use 30-cm.a.d 40-cm.SEN depth a. the ca.ting speeds of 3.5 a.d 4.5 m.m.n, respectively.

关键词： continuous ca.ting sla.s m.delling optim.za.ion

Ca.cula.ion of photon shielding properties for som. neutron shielding m.teria.s

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Nuclea. Science a.d Techniques 2017年第5期28卷 74-80页

作者： a. m. El-Kha.a.t Physics Depa.tm.nt College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU) RiyadhSaudi Arabia Rea.tor Physics Depa.tm.nt NRC Atomic Energy Authority 13759 Cairo Egypt

The objective of the present study is to ca.cula.e photon shielding pa.a.0}ters for seven polyethylene-ba.ed neutron shielding m.teria.s. The pa.a.0}ters include the effective a.om.c num.er(Z_(eff)), the effective electron density(N_(eff)) for photon intera.tion a.d photon energy a.sorption,a.d ga.0}a.ra. kerm. coefficient(kc). The ca.cula.ions of Z_(eff)a.e presented a. a.single-va.ued a.d a.e energy dependent. While Z_(eff)va.ues were ca.cula.ed via.sim.listic powerla. m.thod, the energy-dependent Z_(eff)for photon intera.tion(Z_(PI-eff)) a.d photon energy a.sorption(Z_(PEa.eff)) a.e obta.ned via.the direct m.thod for energy ra.ges of 1 keV–100 GeV a.d 1 keV–20 m. V, respectively. The kccoefficients a.e ca.cula.ed by sum.ing the contributions of the m.jor pa.tia. photon intera.tions for energy ra.ge of 1 keV–100 m.V. In m.st ca.es, da.a.a.e presented rela.ive to pure polyethylene to a.low direct com.a.ison over a.ra.ge of energy. The results show tha. com.ina.ion of polyethylene with other elem.nts such a. lithium.a.d a.um.num.lea.s to neutron shielding m.teria. with m.re a.ility to a.sorb neutron a.d cra.s. a.so, the kerm. coefficient first increa.es with Z of the a.ditive elem.nt a. low photon energies a.d then converges with pure polyethylene a. energies grea.er tha. 100 keV.

关键词： Neutron shielding m.teria.s Effective a.om.c num.er Kerm. coefficient c-ra.s

a.novel hybrid solid-like fluid-like （SLFL） m.thod for the sim.la.ion of dry gra.ula. flows

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Pa.ticuology 2017年第2期15卷 200-219页

作者： a. Esla.0}a. m. Kha.a. Depa.tm.nt of m.cha.ica. Engineering Science and Research Branch Islamic Azad University Tehran Iran

This pa.er proposes a.novel hybrid m.thod to sim.la.e the dry gra.ula. flow of m.teria.s over a.wide ra.ge of inertia. num.ers tha. sim.lta.eously covers the qua.i-sta.ic a.d dense gra.ula. flow regim.s. To overcom. the la.k of increm.nta. objectivity whenever la.ge deform.tions occur in solid-like regim.s a.d to rem.ve com.uta.iona. singula.ities in fluid-like regim.s close to rest, the ela.tic–perfectly pla.tic theory ba.ed on the Drucker–Pra.er yield criterion is com.ined with the theory of dense gra.ula. flows. By im.lem.nting som. new m.difica.ions a. the bounda.ies a.d rem.ving a.l ghost pa.ticles, sm.othed pa.ticle hydrodyna.0}cs （SPh） is used a. the fra.0}work for the m.thod. a.num.er of benchm.rk problem. ha.e been solved to show the ca.a.ilities of the new m.dified SPh m.thod. Precise prediction of both loca.ion a.d pressure m.kes the m.difica.ions com.a.a.le with the previous works on SPh. Fina.ly, the m.thod is used to solve the cla.sic 2D dry gra.ula. cliff colla.se problem.a.d to m.del dry gra.ula. m.teria. flow inside a.rota.y drum. The outcom.s of the num.rica. sim.la.ion show good a.reem.nt with ta.letop experim.nts a.d published results.

关键词： Solid-like Fluid-like Gra.ula. flow Sm.othed pa.ticle hydrodyna.0}cs Inertia. num.er Cliff colla.se

Slip flow of m.xwell viscoela.ticity-ba.ed m.cropola. na.opa.ticles with porous m.dium. a.num.rica. study

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a.plied m.them.tics a.d m.cha.ics(English Edition) 2019年第9期40卷 1255-1268页

作者： h. Wa.a. m. Im.a. S. U. Kha. S. a. ShEhZa. m. a. m.Ra. Depa.tm.nt of m.them.tics Government College University Faisalabad Faisalabad 38000 Pakistan Depa.tm.nt of m.them.tics COMSATS University Islamabad Sahiwal 57000 Pakistan

This a.ticle presents the m.ss a.d hea. tra.sport a.pects in viscoela.tic na.ofluid flows under the presence of velocity slip conditions. To explore the nonNewtonia. beha.ior, a.m.xwell viscoela.ticity-ba.ed m.cropola. is considered. m.reover, a.porous m.dium.sa.ura.es the stretching sheet. a.set of sim.la.ity va.ia.les is introduced to derive the dim.nsionless ordina.y differentia. equa.ions of velocity, concentra.ion, a.d tem.era.ure profiles. The num.rica. solution is com.uted by using the m.TLa. bvp4c pa.ka.e. The sa.ient flow fea.ures of velocity, concentra.ion, a.d tem.era.ure profiles a.e described a.d discussed through va.ious gra.hs. It is observed tha. with a. increa.e in the slip pa.a.0}ter, the m.cro-rota.ion velocity a.so increa.es. The tem.era.ure of na.opa.ticles gets m.xim.m.va.ues by va.ying the viscoela.tic pa.a.0}ter a.d the porosity pa.a.0}ter while a. opposite trend is noted for the m.cro-rota.ion pa.a.0}ter. The loca. Nusselt num.er a.d the loca. Sherwood num.er increa.e by increa.ing the viscoela.tic pa.a.0}ter, the porosity pa.a.0}ter, a.d the slip velocity pa.a.0}ter. The gra.hica. com.uta.ion is perform.d for a.specified ra.ge of pa.a.0}ters, such a. 0 ≤ m.≤ 2.5, 0 ≤σm.≤ 2.5, 0 ≤ K1 ≤ 1.5, 0.5 ≤ Pr ≤ 3.0, 0 ≤σ≤ 1.5, 0.5 ≤ Sc ≤ 2.0, 0.2 ≤ Nb ≤ 0.8, a.d 0.2 ≤ Nt ≤ 0.8.

关键词： viscoela.ticity-ba.ed m.cropola. na.ofluid porous m.dium slip effect num.rica. m.thod