Journal of Porous Media,17(2):129–142(2014) NUMERICAL STUDY ON TURBULENCE EFFECTS IN POROUS BURNERS
M.E.Nimvari,1M.Maerefat,1,?M.K.El-Hossaini,2&N.F.Jouybari1
1Department of Mechanical Engineering,Tarbiat Modares University,P.O.Box14115-143, Tehran,Iran
2Energy Research Centre,Research Institute of Petroleum Industry,P.O.Box14665-137,Tehran, Iran
?Address all correspondence to M.Maerefat E-mail:maerefat@modares.ac.ir
Original Manuscript Submitted:1/31/2013;Final Draft Received:8/27/2013
This paper presents numerical simulation of combustion of air/methane mixture in a cylindrical porous burner while the turbulence between the pores of porous medium has been considered via an explicit model.Results of both laminar and turbulence models are presented and compared for different equivalence ratios and several pore diameters.The turbulent kinetic energy increases along the burner due to the turbulence created by the solid matrix with a sudden jump at the
?ame front due to the thermal expansion.Also,because of the higher diffusion due to the turbulence,the reactants become more preheated,leading to an increase in the burning speed in comparison to the laminar results.Higher burning speed
in turbulence cases decreases the?ame temperature and shifts the maximum temperature location toward downstream
of the burner.It is found that at higher equivalence ratios,the effects of turbulence become more signi?cant.Taking into account the turbulence effects results in burning speeds which are in good agreement with the experimental data. Although the increase of pore diameter in the laminar model decreases the burning speed due to lower volumetric heat transfer between the phases,higher effective diffusion results in higher burning speed in the turbulence model.
KEY WORDS:porous burner,turbulence,combustion,burning speed,temperature
1.INTRODUCTION
Most of the reported studies on porous burner have con-sidered laminar?ow regime inside the porous media. Investigations showed that transient regime takes place inside the porous media for pore-based Reynolds num-bers(Re p)larger than110and fully turbulent regime occurs for Re p larger than300(Dybbs and Edwards, 1984).It is evident that for a?uid with a?xed vis-cosity and mean?uid speed,the transition may be ob-tained at Re p lower than110in the random structure of the porous medium(Lage,1998).Obviously,important parameters such as?ame thickness,gas and solid tem-peratures,species concentration distribution,and burn-ing speed are all affected by the turbulence within the porous burner(Lage,1998;Kamal and Mohamad,2005).Discrepancy between calculated results and experimen-tal data for gas and solid temperatures and burning speed has been reported in the literature(Hsu et al.,1993;Hsu and Matthews,1993;Hackert et al.1999;Malico et al., 2000;Maerefat et al.,2011).This discrepancy is more signi?cant at higher equivalence ratios corresponding to higher burning speeds.Hsu and Matthews(1993)and El-Hossaini et al.(2008)have predicted burning speed and pollutant emissions versus equivalence ratio numerically and found that the deviation from the experimental results increases as the equivalence ratio of mixture approaches the stoichiometric value.This was attributed to the more pronounced turbulence effects as the burning speed in-creases near the stoichiometric mixture,which was not considered in their laminar model.Pore scale laminar cal-culation of Hackert et al.(1999)showed that indepen-
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NOMENCLATURE
c F Forchheimer coef?cient W k molecular weight of the k th
cμ,c1,c2constants in the k?εmodel species(kg kmol?1)
c k constant in the extra production term W mean molecular weight of the
for k?εmodel mixture(kg kmol?1)
C pf constant pressure heat capacity z,r cylindrical coordinates(m)
of the?uid(J kg?1K?1)Y k mass fraction of the k th species
C pk constant pressure heat capacity
of the k th species(J kg?1K?1)Greek Symbols
D deformation rate tensor(s?1)εdissipation rate of k(m2s?3)
D kN binary diffusion coef?cient(m2s?1)μ?uid dynamic viscosity(kg m?1s?1)
D disp dispersion mass diffusivity(m2s?1)μt?macroscopic turbulent viscosity
d p por
e diameter(m)(kg m?1s?1)
h v volumetric heat transfer coef?cientν?uid kinematic viscosity(m2s?1)
(W m?3K?1)νt?macroscopic turbulent kinematic
h k speci?c enthalpy of the k th viscosity(m2s?1)
species(kJ kmol?1)ρf?uid density(kg m?3)
I turbulent intensity(u′/ˉu)σStephan–Boltzmann constant(W m?2K?4)
I(?r,?s)radiation intensity(W m?2sr?1)σT turbulent Prandtl number for T f
K permeability(m2)σk turbulent Prandtl number for k
K conductivity tensor(W m?1K?1)σεturbulent Prandtl number forε
k a absorption coef?cient(m?1)σs scattering coef?cient(m?1)
k turbulent kinetic energy(m2s?2)?porosity
k f?uid thermal conductivity(W m?1K?1)Φscattering phase function(sr?1)
k s solid thermal conductivity(W m?1K?1)˙ωk molar rate of production of the k th species k disp dispersion thermal conductivity per unit volume(kmol m?3s?1)
(Wm?1K?1)?solid angle(sr)
Nu v volumetric Nusselt number,h v d2p/k f
P pressure(Pa)Special Characters
R universal gas constant(kJ kmol?1K?1)φgeneral variable
Re p Reynolds number based on pore diameter,φ′?uctuation from time average ofφρf u D d p/μ?φ?i intrinsic average ofφSc t turbulent Schmidt numberˉφtime average ofφ
T s solid temperature(K)()s/f solid/?uid
T f?uid temperature(K)()eff effective value
T temperature(K)()b blackbody
u velocity vector(m s?1)()in inlet value
u D Darcy or super?cial velocity(m s?1)()out outlet value
dent of volume averaging or pore scale modeling,devi-ation from experimental data would exist,especially at higher equivalence ratios.In order to eradicate the dis-crepancy,several researchers(Hsu et al.,1993;Howel et al.,1996;Hackert et al.,1999;Kamal and Mohamad,2005)concluded that turbulence models or at least tran-sient calculations would be needed to accurately model combustion in porous media at high equivalence ratios. Lim and Matthews(1998)showed that better agreement between numerical predictions and experimental results
Journal of Porous Media
Numerical Study on Turbulence Effects in Porous Burners131
would be obtained if the effects of turbulence on combus-tion in porous media are considered.Their work has been conducted on the basis of an extension of the standard k?εmodel of Jones and Launder(1972)with discard-ing theεequation using an appropriate length scale.The standard k?εmodel does not account for the additional viscous and form drag effects imposed by the solid ma-trix to the?ow,while the undeniable role of the solid matrix in?uid?ow and enhancement or quenching of turbulence and modi?cation of the turbulent energy spec-trum distribution in porous media has been expressed by several researchers(Schreck and Kleis,1993;Hall and Hiatt,1994;Wharton et al.,2005;Horton and Pokrajac, 2009).In the model of Lim and Matthews(1998),turbu-lence generation due to the porous matrix has been con-sidered and assumed to be a function of axial velocity and mean pore diameter of the porous matrix.Hall and Hi-att(1994)showed that the levels of turbulence intensities normalized by the area mean velocity ranged from0.05 to0.6for Re p numbers in the range of17to200that usu-ally occur in conventional porous burners.Measurement of turbulence intensities by Wharton et al.(2005)for re-acting and nonreacting?ows showed that combustion has signi?cant effects on the?ow characteristics and turbu-lence intensity in the porous https://www.doczj.com/doc/c914090847.html,ing a microscopic perspective,Dong et al.(2008)have numerically studied turbulent two-phase?ow in a combustion chamber of an internal combustion engine in which a porous media is embedded as a heat regenerator.The results showed that the spray/porous interaction has substantial in?uences on the fuel–air mixture formation and homogenization in the combustion chamber,which could be very advantageous in engine applications.The results also are useful for nu-merical modeling of liquid fuel porous burners where the vaporization of liquid fuel droplets takes place in the porous burner by the high temperature solid matrix.
In recent years,due to the essential in?uence of the turbulence on porous media processes,the study of tur-bulence characteristics in porous media has received ex-tensive attention by researchers in the?eld(Antohe and Lage,1997;Nakayama and Kuwahara,1999;Pedras and de Lemos,2001;Teruel and Rizwan-uddin,2009).To treat the turbulent?ows through porous media mathe-matically,most researchers follow a traditional macro-scopical approach for low Re p?ows in the porous me-dia,in which the governing equations are obtained by a volume-averaging over a representative elementary vol-ume(REV).A common modeling approach is to apply time averaging for handling the turbulence,and space av-eraging for handling the morphology to the microscopic equations.Almost all of the models derived to simu-late turbulence in porous media are based on the clear ?uid k?εmodel being modi?ed to consider the effect of solid matrix.The diversity of these models is due to not only the averaging order,but also the different def-initions of the macroscopic turbulence quantities,such as the turbulent kinetic energy(TKE)and the dissipa-tion rate(Teruel and Rizwan-uddin,2009).Furthermore, these models have been employed extensively for non-reacting?ows(Yarahmadi et al.,2010,Nimvari et al., 2012),and only few researches included the reacting tur-bulent?ow in the porous media.de Lemos(2009)has presented one-dimensional simulation of turbulent com-bustion of an air/methane mixture in porous burner using the turbulence model proposed by Pedras and de Lemos (2001).As an extension to his work,de Lemos(2010) has modi?ed the Arrhenius expression so that it would be applied to turbulent combustion in the porous me-dia.The results showed that the double decomposition concept(de Lemos,2006)applied to Arrhenius expres-sion results in additional terms,which could be associ-ated with the mechanism of dispersion and turbulence in porous media.Recently Yarahmadi et al.(2011)numeri-cally simulated the porous burner,experimentally studied by Trimis and Durst(1996),using the turbulence model proposed by Pedras and de Lemos(2001).Their results showed that the turbulence model predicts gas and solid temperature closer to the experimental data of Trimis and Durst(1996).
Motivated by the foregoing,in the present study the effects of turbulence on the reacting?ow in cylindrical porous burner have been studied numerically.Transport equations are written in their time and volume-averaged form and a volume-based statistical turbulence model is applied to simulate turbulence generation due to the porous matrix.Local thermal non equilibrium between the gas and the solid phases is considered.Thus,separate energy equations are solved for the two phases.The radia-tive part of the solid phase energy equation is obtained us-ing the discrete ordinate https://www.doczj.com/doc/c914090847.html,E,gas and solid tem-peratures,and burning speed pro?les are presented at dif-ferent equivalence ratios and several pore diameters and compared with the results of laminar calculations and also with the available experimental data.
2.PROBLEM CONSIDERED AND GOVERNING
EQUATIONS
The geometry of the problem is schematically shown in Fig.1,where a two layer porous burner is assumed with
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FIG.1:Schematic of the studied porous burner inert porous material and negligible catalytic effects.The burner is two-dimensional and has an axisymmetric cir-cular cross section with10cm diameter and10.16cm length.These dimensions have been used in order to vali-date the present numerical results against the experimen-tal data reported by Chaf?n et al.(1991)and also numer-ical results of Hsu et al.(1993)and Lim and Matthews (1998).The porous burner consists of two zones:preheat-ing zone made of partially stabilized zirconia(PSZ)and a combustion zone with larger pore size also made of PSZ with constant material properties shown in Table1(Barra et al.,2003).The GRI3.0chemical reaction mechanism is used for the combustion of the methane.The GRI3.0 consists of53species with325elementary chemical re-actions.The thermophysical properties of the gas mixture are a function of temperature and species concentration and are calculated using the CHEMKIN subroutines of Kee et al.(1993).Gaseous radiation has been neglected in comparison to the solid radiation,thus radiation has been considered only between the particles that comprise the porous matrix.The air/methane mixture is treated as incompressible ideal gas and the density of the mixture is determined using the perfect gas equation.There are two approaches to simulate the premixed?ame:(i)burner stabilized?ame in which the inlet velocity is speci?ed and the?ame location is then part of the calculation,and (ii)free propagating?ame in which the?ame location is speci?ed and the inlet velocity will be an eigenvalue and must be determined as a part of the solution(Dia-mantis et al.,2002).The second approach is followed in one-dimensional simulation in order to evaluate appropri-ate initial condition for two-dimensional simulation in the present study.
2.1Macroscopic Continuity and Momentum
Equations
Flow in the porous burner is described by the Forch-heimer’s extended Darcy equation together with the macroscopic turbulence model proposed by Pedras and de Lemos(2001).Under axisymmetric geometry,New-tonian?uid,steady and turbulence?ow assumptions,the continuity and momentum equations are as follows(de Lemos,2006):
?·(ρfˉu D)=0(1) where the Dupuit–Forchheimer relationship,ˉu D=??ˉu?i,has been used and?ˉu?i identi?es the intrinsic av-erage of the local time-averaged velocity vectorˉu(de Lemos,2006).
TABLE1:Solid property data used for computations(Barra et al.,2003)
Preheating zone(upstream)Combustion zone(downstream)
Porous media PSZ with25.6pore/cm PSZ with3.9pore/cm
Porosity0.8350.87
Extinction coef?cient1707m?1376m?1
Conductivity0.2W/m K0.1W/m K
Scattering albedo0.80.8
Coeff.of Eq.(12)C0.6380.146
Coeff.of Eq.(12)m0.420.96
Radiation emissivity 1.0
Density510kg/m3
Heat capacity824J/kg K
Journal of Porous Media
Numerical Study on Turbulence Effects in Porous Burners 133
?·(ρf
ˉu D ˉu D
?
)
=??(??ˉP ?i
)+?·(μ?ˉu D )+?·(?ρf ?′′?i )?[μ?K ˉu D +c F ?ρf |ˉu D |ˉu D
√K ](2)
where ?ρf ?′′?i
is the macroscopic Reynolds stress tensor (MRST)modeled as ?ρf ??u ′u ′?i =ρf νt ?2?D ?v ?23?ρf ?k ?i
I (3)
where
?ˉD ?v =12[?(??ˉu ?i )+[?(??ˉu ?i )]T ](4)is the macroscopic deformation tensor and νt ?is the
macroscopic turbulent kinematic viscosity that is mod-eled similar to the case of the clear ?uid ?ow (de Lemos,2006);
νt ?=μt ?/ρf =c μ?k ?i 2/?ε?i
(5)
The last two terms in Eq.(2)are known as the Darcy
and the Forchheimer drags.These terms represent the vis-cous and net pressure forces felt by the ?uid after passing through the porous matrix.
2.2Macroscopic Equations for Turbulence Transport equations for TKE,?k ?i
=?u ′·u ′?i /2,and
dissipation rate,?ε?i =ν??u ′′?i ,are pre-sented by Eqs.(6)and (7),respectively (de Lemos,2006).?·(ˉu D ?k ?i )=?·[(ν+νt ?σk
)?(??k ?i
)]
+P i
+?G i k ???ε?i
(6)?·(ˉu D ?ε?i )=?·[(ν+νt ?σε
)?(??ε?i
)]
+(c 1P i
?c 2??ε?i )?ε?i
?k ?i +?G i ε(7)where P i =??u ′u ′?i
:?ˉu D is the production rate of ?k ?i
due to gradients of ˉu D .These macroscopic turbu-lence model equations present two extra source terms:G i k =c k ?k ?i |ˉu
D |/√K and G i
ε=c k c 2?ε?i |ˉu D |/√K ,which represent internal production of the TKE and its dissipation rate due to the presence of solids (de Lemos,2006).
2.3Macroscopic Gas and Solid Energy
Equations
Macroscopic energy equations are obtained for both the ?uid and solid phases by also applying time and volume average operators to the instantaneous local equations.As in the laminar ?ow case,volume integration is performed over an REV .After including the heat released due to the
combustion reaction,one gets for both phases ?ρf C pf ??T f
?i ?t +(ρf C pf ˉu D ??M ∑k =1ρf C pk ×D kN ??Y k ?i )·??T f ?i =?·[K e?,f ·??T f ?i ]
+h v (?T s ?i ??T f ?i )+?M ∑k =1
h k ?˙ω
k ?i
(8)
0=?·[
K e?,s ·??T s ?i ]?h v (?T s ?i ??T f ?i )
??q rad (9)
where K e?,f and K e?,s are the effective conductivity ten-sors for the ?uid and the solid,respectively,given by K e?,f =[?k f +?ρf C P ,f νt ?
σT
+k disp ]
I (10)
K e?,s =[(1??)k s ]I (11)
In the solid phase energy equation,?q rad is the gradient
of thermal radiation from the solid.Radiation ?ux is cal-culated by using the radiative transfer equation (RTE)in a cylindrical enclosure with absorbing–emitting–scattering medium.In Eqs.(8)and (9),the heat transferred between the
two phases has been modeled by means of a volumetric
heat transfer coef?cient.So far,several numerical and ex-perimental researches have been done to calculate this co-ef?cient for different geometries and different ?ow condi-tions.The volumetric heat transfer coef?cient between the
gas and the solid is estimated from the experimental cor-relation of Younis and Viskanta (1993)given by Eq.(12)where C and m are constant values,given in Table 1.h v =k f Nu v /d 2p ;Nu v =C Re m p (12)The experimental correlation [Eq.(12)]is valid for the Re p range accounted in the present study regardless of
the ?ow regime (Younis and Viskanta,1993).Volume 17,Number 2,2014
134Nimvari et al.
2.4RTE
To determine the radiative heat ?ux,the solid and
?uid phases are considered as a single continuum ho-mogeneous phase where the RTE is solved.The heat source/sink term ?q rad ,in the solid phase that appears in Eq.(9),is calculated from Eq.(13):
?q rad =k a (4πI b ?∫
4πI d ?)(13)Radiative intensity is obtained by solving the RTE
[Eq.(14)]
dI (?r ,?s )
ds
=?[k a (?r )+σs (?r )]I (?r ,?s )+S (?r ,?s )(14)where the source function,S (?r ,?s )is S (?r ,?s )=k a (?r )I b (?r )+σs (?r )4π∫4π
I (?r ,?s ′)Φ(?s ′,?s )d ?′(15)
The radiation intensity I (?r ,?s )is a function of position and direction.In Eq.(14),the expression on the left-hand side
represents the gradient of the intensity in the speci?ed di-rection ?s .The ?rst term on the right-hand side represents intensity loss due to absorption and out-scattering.The two source terms in Eq.(15)represent intensity gained due to emission and in-scattering.The porous medium is assumed to be gray,homogeneous,and isotopic scattering (Φ=1)(Modest,2003).
2.5Species Concentration The transport equation for the species read by Eq.(16)as reported by de Lemos (2006):
?ρf ??Y k
?i ?t +?·(ρf ˉu D ?Y k ?i )=??·(ρf D e?
×??Y k ?i )+?W k ?˙ωk ?i
(16)The effective mass transport tensor D e?is de?ned as D e?=[
D kN +νt ?
Sc t
+D disp ]I (17)In Eqs.(10)and (17),k disp and D disp are the dispersion effects on the temperature and species distributions,re-spectively.Since the main purpose of the present study is to investigate the effects of turbulence on the combustion
in the porous media,the dispersion effects are neglected;
hence,the last terms on the right-hand side of Eqs.(10)and (17)are not considered.
Density ρf in the above equations is determined from
the perfect gas equation for a mixture of perfect gases:
ρf =P W
f
(18)where P is the absolute pressure,R is the universal gas
constant,and W is the mean molecular weight of the mix-ture.
Further,the constants used in Eqs.(5),(6),(7),(10),
and (17)of the macroscopic k ?εmodel are the same given by Jones and Launder (1972)for clear medium (?=1and K →∞),except c F and c k which are in relation to the turbulence in porous media (Pedras and de
Lemos,2001).They read
c μ=0.09,c 1=1.44,c 2=1.92,σk =1.0,
σε=1.3,σT =0.9,Sc t =0.7,c F =0.55,c k =0.28(19)
3.BOUNDARY CONDITIONS The inlet boundary conditions are assumed to be ?at pro-?les for axial velocity,turbulence quantities,gas tem-perature,and species concentration.The mechanism of heat transfer between the solid matrix and the surround-ing takes place by radiation.u =u in ,v =0,T f =T f,in ,k =3(u in I )2/2,
ε=k 3/2,Y k =Y k,in ,k =1,2,...,M (1??)k s
?T s ?z
+(1??)εin σ(T 4s ?T 4
0)=0(20)
At the exit,the fully developed condition is speci?ed for all variables except the solid temperature.?u ?z =?v ?z =?k ?z =?ε?z =?T f ?z =?Y k ?z
=0,(1??)k s ?T s ?z +(1??)εout σ(T 4s ?T 40)=0(21)Here,T 0is the ambient temperature,I is the inlet turbulent intensity,and εis the emissivity of the solid matrix.These
values are equal to 298K,0.05%,and 1.0,respectively.
At the axis,symmetric condition is imposed for all variables.v =
?u =?k =?ε=?T f =?T s =?Y k =0(22)Journal of Porous Media
Numerical Study on Turbulence Effects in Porous Burners135 At the burner wall,the usual no-slip and impenetrabil-
ity conditions are applied to the velocity components in
momentum equation and the gradient of the other vari-
ables normal to the surface are set to zero.
v=u=?k
?r
=
?ε
?r
=
?T f
?r
=
?T s
?r
=
?Y k
?r
=0(23)
The burner surfaces are assumed to be gray,emitting and re?ecting diffusely.Therefore,the intensity boundary condition for outgoing direction is
I(?r)=εI b(?r)+1?ε
π
∫
?s·n<0
I(?r,?s)|?s·n|d?(24)
where n,ε,and?are unit vector normal to the surface, emissivity,and solid angle,respectively(Modest,2003).
4.NUMERICAL SIMULATION
The numerical method employed for discretizing the gov-erning equations is the control-volume approach with a collocated grid.The governing equations are solved by an in-house FORTRAN code.The hybrid scheme,Up-wind Differencing Scheme(UDS)and Central Differenc-ing Scheme(CDS),is used for interpolating the con-vection?uxes.The well-established SIMPLE algorithm (Patankar,1980)is followed for handling the pressure–velocity coupling.Standard wall functions have been employed to calculate the?ow in the proximity of the walls at turbulent?ow condition.To solve the chemical species systems of conservation equations together with the gas?ow energy equation,the explicit Runge–Kutta–Chebyshev scheme of Verwer(1996)is used.While the solid energy equation is solved through?nite volume dis-cretization,the thermal radiation is modeled using the dis-crete ordinate method(DOM).Individual algebraic equa-tion sets are solved by the strongly implicit procedure (SIP)of Peric and Ferziger(1990).The maximum residue allowed for convergence check is set to10?6,being the variables normalized by appropriate reference values.The solution procedure is thus as follows:
1.At the?rst step,one-dimensional conservation equa-
tions are solved in order to obtain approximate values of gas temperature and species concentra-tions.These values are used as initial values in two-dimensional solutions,signi?cantly reducing the computational costs.
https://www.doczj.com/doc/c914090847.html,ing the above-mentioned initial values,thermo-
physical properties are calculated.
3.The?ow?eld is calculated from the momentum
equation.
4.Turbulent kinetic energy and dissipation rate equa-
tions are solved and the value of turbulent viscosity is updated.
5.To ascertain gas temperature pro?les and species
concentrations,transient solutions of energy and species continuity equations are carried out
6.Radiative heat transfer and energy conservation
equations of the solid matrix are solved;new tem-perature pro?les and species concentrations are ob-tained,and the thermophysical properties are up-dated.
7.The calculation procedure is repeated from step3,
until the required accuracy is achieved.
The calculations started on coarse grid of about12–20 points in the?ow direction and an adaptive procedure is used to re?ne the grid points(Kee et al.,1993).
5.RESULTS AND DISCUSSION
The use of two layer porous burner with different charac-teristics allows the stabilization of the?ame over a range of inlet velocities for each equivalence ratio.This range of stable velocities is investigated and clearly demonstrated in the literature(Chaf?n et al.,1991;Barra et al.,2003; Smucker and Ellzey,2004).In this way,for each equiva-lence ratio,minimum and maximum velocities exist that correspond to?ash back and blow-off limit,respectively. The results of laminar and turbulence models are com-pared at the maximum velocity(blow-off limit)for each equivalence ratio in the present study.
Figure2represents TKE distribution at the centerline of burner for the combustion of stoichiometric mixture. The TKE pro?le shows a sudden jump at the?ame front and then remains almost constant afterward with the slight reduction at the end of burner.This trend is in accor-dance with the results of simulation reported by de Lemos and Pevim(2012).The porous burner characteristics and ?ame location are assumed to be the same as de Lemos and Pevim(2012)in order to verify the present results. For a?at velocity pro?le quickly formed inside the porous media,the velocity gradient is trivial and the production rates of TKE are mostly due to the solid matrix.As in-troduced in the TKE equation[Eq.(6)],the correlation
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136Nimvari et
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FIG.2:Dimensionless turbulent kinetic energy(k?) along the burner;present work versus result of de Lemos and Pevim(2012)
determined for this generation term varies asˉu D.Ther-mal expansion in combustion results in a lower?uid den-sity and higher?ow velocity.Therefore,the velocity takes large values in the combustion zone compared to the ve-
locity in the preheat zone,which encourages the G i
k term.
Thus,TKE reaches higher values in the combustion zone. The under-prediction of present results in the combustion zone refers to lower velocity due to lower temperature predicted by the detailed combustion mechanism used in the present study.In the work of de Lemos and Pevim (2012)the single-step global mechanism has been used to model the complete combustion of methane,resulting in higher temperature and consequently higher TKE at the combustion zone.The reduction of TKE at the end of burner is due to lower temperature,and hence lower velocity,because of radiation to the downstream cold en-vironment which is absent in the study of de Lemos and Pevim(2012).
Figure3illustrates the values of TKE at the center-line of the porous burner in different equivalence ratios. As shown in Fig.3,the amount of the TKE decreases in the lower equivalence ratios because of the lower burning speeds.The generation of turbulence in the porous me-dia reduces with the decrease of burning speed in lower equivalence ratios.This effect has been considered in the
numerical modeling by decreasing the G i
k term in the
TKE equation.For the equivalence ratio0.5,Re p is
al-
FIG.3:TKE for different equivalence ratios at the cen-terline of the burner
most60and the regime of the?ow is laminar(Dybbs and Edwards,1984);the corresponding curve shown in Fig.3has negligible amount of TKE.Therefore,for low speed?ows,the levels of the TKE will remain low even if a turbulence model is applied.This result emphasizes the correctness and stability of the developed turbulence code.For the equivalence ratio1.0,Re p is almost four times greater,entering a range where intrapore turbulence is usually assumed to be signi?cant(de Lemos,2009).As shown in Fig.3,for the equivalence ratio1.0,the TKE is signi?cant and it is necessary to use a turbulence model.
There is large inconsistency in burning speed between the experimental results and those of the previous re-searches(Hsu and Matthews,1993;Hackert et al.,1999;
El-Hossaini et al.,2008),which considered?ow to be laminar.The burning speed as a function of equivalence ratio is shown in Fig.4for both laminar and turbulence models.The computed values have been compared with the experimental results of Chaf?n et al.(1991).Compar-ison is also made with the one-dimensional laminar cal-culation of Hsu and Matthews(1993)and the turbulent simulation of Lim and Matthews(1998).In Fig.4,the volumetric heat transfer coef?cient is assumed to be con-stant and equal to107W/m3K,the same as used by Hsu and Matthews(1993)and Lim and Matthews(1998)for authentic comparison.In other cases,the volumetric heat transfer coef?cient has been calculated by Eq.(12).Al-
Journal of Porous Media
Numerical Study on Turbulence Effects in Porous Burners
137
FIG.4:Comparison of the present results with the ex-perimental data of Chaf?n et al.(1991)and numerical re-sults of Hsu and Matthews(1993)and Lim and Matthews (1998)for burning speed
though the results of laminar?ow are far from the experi-mental data,especially at high equivalence ratios,they are in good agreement with the laminar calculations of Hsu and Matthews(1993),further evidence for validation of calculations in the present study.As shown in Fig.4,the results of burning speed are essentially equal when using laminar or turbulence models in the lean mixtures,which corroborates the observation made above(Fig.3)about negligible TKE in low velocity?ows.For equivalence ratio less than0.65,the velocity and Re p inside porous burner is low and the turbulence effect is trivial.An in-crease in the equivalence ratio leads to higher burning speed and higher Re p inside porous burner.For an equiva-lence ratio more than0.65,the computed values compare well with the turbulence simulation of Lim and Matthews (1998).As illustrated in Fig.4,the offset between nu-merical and experimental results decreases in turbulence simulation.For the gas phase,heat release from the com-bustion is mostly balanced by diffusion in a thin reaction zone,and the diffusion is balanced by convection in the preheat zone of the?ame(Diamantis et al.,2002).
Turbulence effect causes an additional diffusion coef?-cient in momentum,gas energy,and species conservation equations.Enhancement of the effective diffusion coef?-cient in the gas energy equation leads to more preheat-ing of the reactants which causes higher burning speed at the blow-off limit.For the laminar model the under-prediction of the blow-off limit at the stoichiometric mix-ture is about45%in comparison to the experimental data. However,almost one-third of the under-prediction error is diminished by including turbulence effects.The remain-ing deviation from the experimental data can be attributed to partial pore blockage in real porous medium of exper-imental burner as mentioned by Wharton et al.(2005) and Lim and Matthews(1998),and also uncertainty in thermophysical characteristics of porous medium such as convective heat transfer coef?cient in volume averaged simulation(Hsu and Matthews,1993;Lim and Matthews, 1998;Diamantis et al.,2002)used in the numerical sim-ulation of the present study and those used in the experi-ment of Chaf?n et al.(1991).The measured burning speed for the stoichiometric mixture is185cm/s,while lami-nar and turbulence calculations lead to104and133cm/s for the stoichiometric mixture,respectively.The higher preheating in turbulence simulation is consistent with the ?ndings of de Lemos(2009),in which the inlet velocity was?xed and the?ame location was a part of numerical solution.Therefore,?ame moves upstream toward the en-trance of the porous burner when the extra preheating due to turbulence is considered.
Figure5shows axial temperature of the two cases of laminar and turbulence models together with available experimental data.Two different porous media materi-als,yttria-stabilized zirconia/alumina composite(YZA) (Mathis and Ellzey,2003)and PSZ(Chaf?n et al.,
1991), FIG.5:Veri?cation of temperature pro?les on the porous burner centerline for equivalence ratio0.7
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138Nimvari et al.
were used in the referred experimental works.We used PSZ in numerical simulation because of the availability of material properties.In the experimental work of Chaf-?n et al.(1991),a ?ame holder was constructed to sta-bilize the reaction zone in the ceramic.It consisted of a water-cooled brass ring inserted between two sections of the porous ceramic.The ?ame was stabilized just down-stream of the ?ame holder and heat was extracted from the burner ?ame holder in order to maintain a stable reaction.This is the reason for the lower temperature of the reac-tion zone in the experimental data of Chaf?n et al.(1991),which is presented in https://www.doczj.com/doc/c914090847.html,ing the turbulence model causes a reduction in the peak ?ame temperature as com-pared with the laminar case and shows a better agreement with the experimental data.Although the porous materi-als of the experimental data of Mathis and Ellzey (2003)are different from the materials of the present numerical model,the temperature pro?les are in good agreement.The calculated gas temperature pro?les are shown in Fig.6for laminar and turbulence models at different equivalence ratios.The dependency of the peak tempera-tures on equivalence ratio is obvious.The highest temper-ature is obtained at the stoichiometric mixture.The gas temperature at the beginning of the preheating zone is al-most independent of the equivalence ratio,but a slightly higher temperature is observed just before ?ame at the stoichiometric combustion.For equivalence ratio 0.5,the velocity is low and the value of TKE is negligible.There-fore,macroscopic turbulent viscosity,which is
respon-
FIG.6:Gas temperature pro?les of porous burner for different equivalence ratios at the centerline of the burner sible for the turbulence effects in numerical solution,is negligible and hence no detectable difference is found be-tween laminar and turbulence gas temperatures.Increas-ing of the equivalence ratio leads to the increase of ve-locity,causes an enhancement of macroscopic turbulent viscosity.Turbulence effects encourage the effective con-ductivity of ?uid and lead to more preheat of the reactants as mentioned above.Although the enhancement of the ef-fective conductivity causes more preheat of the reactants,higher inlet velocity leads to increase of the bulk convec-tion of the cold inlet reactant (Diamantis et al.,2002).Consequently,the temperature obtained by the turbulence model is slightly lower in the preheat zone.In the com-bustion zone,conduction is balanced by combustion heat release.Since turbulence intensi?es conduction,the heat release is dispersed in both preheat and post-combustion zones (Yarahmadi et al.,2011).So,for the turbulence model,the peak temperature of ?ame is lower than that of the laminar model.The maximum temperature difference between laminar and turbulence models is 100and 140K for equivalence ratios 0.7and 1,respectively.The signif-icant effect of the lower and ?atter gas temperatures in turbulence model leads to the reduction of NO formation,which strongly depends on the gas temperature (Williams et al.,1992).Location of the maximum temperature in the turbulence model is slightly shifted toward downstream of the burner.Since increasing of the inlet velocity in the turbulence model leads to a comparably smaller residence time in the combustion region,some of the reversible re-actions take place at the downstream of the burner (Bren-ner et al.,2000)and consequently the location of the peak temperature is shifted toward downstream.A reduction in the temperature is observed at the end of the burner inde-pendent of the equivalence ratio and mathematical model due to the radiation from the solid particle to the cold en-vironment.The solid temperature at the end of the burner is higher in the laminar model,which results in higher ra-diation heat transfer to the environment in comparison to the turbulence model.Therefore,the reduction of the gas temperature is higher in the laminar model because of the higher heat exchange between phases.Consequently,the temperature difference between the turbulence and lami-nar models reduces at the end of the burner.
Figure 7shows the solid temperature pro?les at the centerline of the porous burner in the case of stoichio-metric mixture for both laminar and turbulence models.In both models,the solid temperature is higher than the gas temperature upstream of the reaction zone due to solid
conduction and solid to solid radiation from the combus-tion zone to the preheat zone.Immediately downstream of
Journal of Porous Media
Numerical Study on Turbulence Effects in Porous Burners
139
FIG.7:Solid temperature pro?les of porous burner at the centerline of the burner for stoichiometric mixture
the reaction zone,the gas temperature exceeds the solid temperature.
Closeness between the gas and solid temperatures in each region depends upon the volumetric heat transfer coef?cient(h v),which is in?uenced signi?cantly by the mean pore diameter(d p)through an inverse relationship according to Eq.(12).Thus,the gas and solid tempera-ture pro?les are very close in the present burner,as a re-sult of the small mean pore diameter corresponding to the high volumetric heat transfer coef?cient.Meanwhile,the volumetric heat transfer equation highly depends on the Re p as shown in Eq.(12).So,by increasing the maximum burning speed in the turbulence model,the value of vol-umetric heat transfer coef?cient increases.However,due to the closeness between solid and gas temperatures in the present simulation,the increasing of volumetric heat transfer coef?cient does not affect the solid temperature. Therefore,by decreasing the gas temperature due to tur-bulence(Fig.6),the corresponding solid temperature re-duces as shown for the base case simulation in Fig.7.
The effect of turbulence in enhancing the volumetric heat transfer coef?cient becomes highlighted when h v de-creases to0.2h v.As shown in Fig.7,by decreasing the h v to0.2h v the solid and gas temperatures are not close any-more and turbulence increases the solid temperature.This trend is opposite of the base case in the present study,sim-ulation performed by h v,and explains the disagreement between the results of the present study and Yarahmadi et al.(2011).The difference between gas and solid tempera-tures is higher in the study of Yarahmadi et al.(2011)due to lower h v and turbulence increases the solid tempera-ture.
The pore diameter,as an important factor in the per-formance of the porous burner,has been investigated ex-tensively in the literature(Hsu et al.,1993;Mishra et al.,2006).TKE for different values of pore diameters is shown in Fig.8.Existence of a solid matrix forces larger eddies than its representative length d P to be dissipa-tive into the interstitial eddy of the pore region.Conse-quently,the size of the largest eddy in the porous media would be the same order of pore sizes.The conventional thought on?ows in porous media is that the turbulent length scales are approximately equal to the mean pore diameter(Wharton et al.,2005).So,the TKE increases rapidly with the increasing of the pore size as shown in Fig.8.In this way,more mechanical energy converts to turbulence energy and use of a turbulence simulation in order to better understand the combustion process is nec-essary.
The burning speeds for laminar and turbulence simu-lations are given in Table2for different pore diameters. Unlike the laminar model,increasing of the pore diameter leads to an increase in the burning speed in the turbulence model.The trend of turbulence results is in good agree-ment with the experimental data of Hsu et al.(1993),in which higher burning speed has been obtained in
higher FIG.8:TKE pro?le for different pore diameters at the centerline of the burner
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140Nimvari et al.
TABLE 2:Comparison of burning speeds of laminar and turbulence models
Burning speed (cm/s)
Pore diameter Laminar model Turbulence model
0.5d p 9496
d p 88121
2d p 80135
pore diameter.In laminar simulation,an increase in the pore size decreases the speci?c surface area and,corre-spondingly,decreases the overall volumetric heat transfer coef?cient between gas and solid phases.Then there is
low preheat of reactants which decrease the burning speed (Sahraoui and Kaviany,1994).Increasing of the burning speed with the increase of pore size in turbulence cases is due to enhancement of the effective diffusion coef?-cient which remedies the reduction of heat exchange ef-fect between two phases.Because of negligible TKE at small pore sizes (as shown in Fig.8),both laminar and turbulence models result in almost equal burning speeds.The difference between laminar and turbulence results in-creases with
the increase of TKE at higher pore sizes.Corresponding pro?les for the gas temperature are pre-sented in Fig.9.For the small pore sizes,the turbulence effect is trivial and no detectable difference between lam-inar and turbulence temperatures is found.With the in-FIG.9:Comparison laminar and turbulence gas temper-ature distributions at the centerline of the burner for dif-ferent pore diameters
crease of pore size,laminar temperature increases slightly
due to reduction in the heat exchange between phases.Despite heat exchange reduction at higher pore sizes,en-hancement of diffusion due to turbulence causes the gas
temperature to be decreased in turbulence calculation.
Turbulence effects are encouraged at higher pore sizes
and consequently the burning speed increases.Therefore,
the residence time of the gas mixture is reduced and the location of peak temperature is shifted more downstream of the porous burner,as shown in Fig.9.
6.CONCLUSION Numerical simulations of combustion including the ef-fects of turbulence in a two layer cylindrical porous burner are investigated.Flow in the porous burner is de-scribed by the Forchheimer’s extended Darcy equation and a volume-based statistical turbulence model is ap-plied to simulate the turbulence generation due to the porous matrix.The combustion reaction has been mod-eled bythe GRI 3.0chemical reaction mechanism and ra-diative heat transfer has been considered by the discrete ordinate method.The effects of equivalence ratio and pore diameter on the TKE,burning speed,and gas and solid temperatures are studied.Based on the results,the fol-lowing conclusions are drawn:–Due to the thermal expansion in the combustion pro-cess and consequently higher velocity,the amount of TKE is higher in the combustion zone.
–While the effects of turbulence are negligible in the combustion of lean mixtures below 0.65,turbulence plays a more important role with the increasing of the equivalence ratio due to higher burning speed.–The burning speed calculated from the turbulence model at the equivalence ratios above 0.65is in bet-ter agreement with the experimental data.In equiva-lence ratios below 0.65,the burning speed is lower and the ?ow regime is laminar;therefore,no de-tectable difference between laminar and turbulence results is observed.–Promoting the heat and mass diffusion due to turbu-lence results in more dissipation of heat released in the combustion to the downstream and upstream re-gions.Therefore,the maximum temperature in the turbulence simulation is lower than that in the lami-nar model.
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Numerical Study on Turbulence Effects in Porous Burners141
–Higher burning speed in the turbulence model de-creases the residence time of the gas mixture and the location of maximum temperature is shifted toward downstream of the burner.
–The larger the pore size,the higher the values of TKE.Increasing the pore size decreases the burning speed in laminar simulation due to lower volumetric heat transfer coef?cient between the phases.Increas-ing the pore size increases the burning speed when turbulence effects are included.Higher diffusion due to turbulence overwhelms the lower volumetric heat transfer coef?cient in higher pore sizes and results in greater burning speed.
–It is concluded that turbulence effects are important and must be considered in higher equivalence ratios or larger pore diameters,and neglecting turbulence in these cases leads to results far from experiments. REFERENCES
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Journal of Porous Media
如何有效地进行跨文化沟通 由于各国的文化存在着多样性的特点，无论是表层的语言、礼仪，还是中层次的建筑、饮食、礼仪或者处于核心层次的民族价值观、思维等等。这就决定我们在进行跨文化沟通的时候会遇到障碍和冲突，如何能有效地跨文化沟通具有十分重要的意义。 在进行跨文化沟通的时候存在障碍的原因是多种多样的，具体来说，文化差异层面的有 1.价值取向.2.思维模式.3.社会规范；另外也取决于沟通双方是否有培养文化差异的意识。 具体来说，可以用文化维度这个概念对跨文化进行分析，它主要有以下5个维度： 第一维度，个人身份的认同，具体来说就可以分为个人主义文化和集体主义文化两大类。个人主义文化的主要特征有：1.关键单位是个人。个人主义文化重视个人自由。2.对物体空间和隐私有更高的要求。3.沟通倾向于直接、明确和个人化。4.商业看作是一种竞争性的交易。集体主义的特征有 1.关键的单位是集体。个人的行动和决策的起点是群体。2.空间和私隐都没有关系重要。3.沟通时直觉式的、复杂的和根据印象进行的。4.商业是相互关联、相互协作的，认为促成结果的是关系而不是合同。以美国文化和中国文化为例，美国文化是具有典型的个人主义色彩，中国文化具有典型的个人主义色彩。 第二维度，权威指数，指国家或社会与人之间的平等程度。具体来说就是高权距离文化和低权距离文化。高权文化往往会导致沟通受到各种限制，因为高权力距离文化倾向于具有严格的层级权力文化结构，下级往上沟通会严重受阻，著名的“玻璃天花板”现象描述的就是在高权距离文化的影响下，组织对外国工作者的排斥。相反，在低权力距离文化影响的组织中，有权力和没权力的人之间的距离更短，沟通可以向上进行叶可以向下进行，更倾向于扁平化、和更民主的层级结构。低权力距离文化正趋于发展的趋势。 第三维度，性别角色权利。具体来说就性别角色在事业、控制和权力的控制程度。 第四维度，对时间的态度，这侧重于区分对目标的长期投入或短期投入。以美国和日本为例。美国喜欢把经商比喻为“打猎”，日本则把经商比喻为“种植水稻”。这可以看出，美国侧重于短期投入要立竿见影的效果，日本则侧重于长期的投资来获取长线的发展。 第五维度，对不确定性的指数。不确定性指数高的国家对含蓄和不确定性因素的接受和容忍程度高，具体体现在法律发条的伸展度等地方。不确定性指数低的国家，对事物的要求高度精确，喜好制定严格的标准和法律。 在现实交流中，这五个维度往往不会单独出现，而是交叉混合，这也和文化的一体性和交融性有着密切的关系。 综合的来说，我们常遇到跨文化沟通障碍有以下几种： 1.自我文化中心主义。这种障碍原因在于，在与人沟通时，习惯性的从自我的文化观念、价值观念、道德体系作标准来看待他人的行为。这种障碍通常会造成漠不关心距离，例如对沟通对方的要求（如特殊的节假日不工作）不加理睬；回避距离，例如因不了解对方的文化礼仪而回避与沟通对方的交流；蔑视距离，例如因不了解对方的宗教生活而对他的行为就行无理干预与批评。 2.文化霸权主义。在进行跨文化沟通时，沟通双方的地位往往不平等。处于
外教一对一英语口语的重要性 随着2008北京奥运、2010上海世博会，中国与国际融合的脚步加快，而英语作为搭建国际化沟通的重要桥梁，受到中国社会各界尤其是企业界的追捧。从长远来看，双语人才，尤其是英语人才，不论在企业国际化人才架构中，还是在中国国际化和平崛起的进程中，都是不可或缺的“基础设施”。外教1对1的培训能很快的提高口语水平，加速双语人才进程。 正是在这样一个国际化浪潮汹涌澎湃的背景下，外教1对1培训的重要性和紧迫性再次被突显，而英语培训过程中经常出现的“缺乏方向”、“缺乏标准”和“缺乏绩效考核”成为企业挥之不去的心病。正是因为这样，我们就不难理解为何“让英语培训机构按企业特定岗位的语言需求培养人才，真正实现企业英语培训与岗位语言胜任能力的无缝对接”、“如何借助第三方语言测评机构的专业力量完善企业英语培训外包机制”、“如何更有效地向英语培训机构下订单”等话题会被企业HR们所关心和热议。 在很多有经验的HR看来，外教英语1对1培训更多是源于改善或提高员工岗位语言胜任能力的直接需求，而企业只有将培训需求和考核标准量化后，才能精准地向英语培训机构提出“订制人才”的标准和要求，这也就是我们常听到的“订单式培训”。在企业内部英语培训的外包操作上，记者最近也注意到越来越多涉外企业的HR们倾向采用“第三方语言测评机构+英语培训机构”的二元培训模式。
那么，HR们又是如何借助英语外教1对1推进企业英语培训的需求下单、绩效考核及效果评估的？首先，企业借助第三方测评机构的专业化力量和专家资源，例如北京的速恩英语，先设计好公司各部门相应的岗位英语胜任标准，然后在培训之前组织相关岗位员工通过相应的英语考试测评，将考试测评的成绩与既定的岗位英语胜任标准进行比照，找出能力与胜任之间的差距，并以此量化成培训需求和向英语培训机构下培训订单的考核标准；其次，英语培训机构根据企业培训订单的培训需求和考核标准，量身定做相应的培训方案，对参训人员进行培训；最后，在培训结束时，再次组织参训人员参与英语测评考试，通过培训前、培训后两次成绩对照以检验“本次英语培训的是否达到既定的预期”、“员工的英语胜任能力通过培训是否得到改善或提高”，做到企业内部英语培训可量化考核和整体绩效评估，避免主观判断。
《跨文化沟通》作业评讲 根据重庆电大制定的教学实施意见和本课程考试要求，为帮助同学们学习和跨文化沟通的理论知识、培养沟通能力和技巧，本课程的作业都采用主观性问题。下面就作业要求作一些简单提示提示内容来自重庆电大），供同学们完成作业时参考。 跨文化沟通作业（1）讲评 论述分析：请看下面的一段话，并按照题目要求进行回答。 在奥地利工作的美国子公司人员有时误认为奥地利人不喜欢他们，因为奥地利人对他们总是一本正经。殊不知，奥地利人不象美国人那样随便，待人直呼其名。由于文化习俗不同，海外子公司人员之间产生误解在所难免。许多美国人不理解，为什么法国人和德国人午餐时喝酒?为什么许多欧洲人不愿意上夜班?为什么海外子公司要赞助企业内的职工委员会或向当地幼儿园教师捐款?对美国人来说，这些活动纯粹是浪费，但对于熟悉当地文化的人来说，这些是非常必要的。 一般来说，在不同文化的融合过程中，会由于以下两个因素而受到阻碍。 一、人们不能清楚地认识自己的文化。有句古诗说：“不识庐山真面目，只缘身在此山中”。人们之所以不能真正的认识自己的文化，也是因为他们总是身处于自己的文化之中。由于从小受到特定文化的熏陶，使其认为在其文化背景下发生的事都是理所当然的，是一种世人皆知的道理。当问起他所处的文化有何特征，有何优缺点时，从未接触过其他文化的人是回答不出来的。他们只能说，从来都是这样。并且，当遇到文化差异时，他们就会用自己认为正常的标准去判断，而对其他的文化标准大惑不解。 如果把其他的文化拿来做比较时，这些问题就可以迎刃而解了。没有比较就没有不同。如果我们不能很好的了解自己的文化，也就无所谓进化。因为我们总是认为自己是对的，而无视其他文化的优势之处。因而也就不能从其他的文化吸取有利于自己发展的东西。 二、对其他的文化认识不够。同样的道理，当我们对其他的文化不能很好的理解时，也会对文化的融合造成障碍。如前所述，当外来文化有利于本土文化发展时就会被吸收。要想达到文化融合就要首先发现外来文化有无有利之处。如果对外来文化的理解上发生扭曲，或者了解片面，就不能公正地判断其是否有利于自身的发展。如果一种优势文化被理解为对其有威胁，它很可能就会被拒之门外。 但是由于我们习惯于从自己的文化角度去审视其他的文化就不会很全面。所以在理解其他文化时应该换个角度，从另一个不同的参照系去理解，并且要对其他文化采取一种超然独立的立场，给与足够的重视认识。 问题： 1、为什么会存在文化差异？ 2、文化差异对于沟通有何影响？
免费外教在线一对一英语口语课程，太平洋英语，三个月与老外畅谈无阻！https://www.doczj.com/doc/c914090847.html, 第1册A版 一、Greetings 问候语 1. Hello! / Hi! 你好！ 2. Good morning / afternoon / evening! 早晨（下午/晚上）好！ 3. I'm Kathy King. 我是凯西·金。 4. Are you Peter Smith? 你是彼得·史密斯吗？ 5. Yes, I am. / No, I'm not. 是，我是。/ 不，我不是。 6. How are you? 你好吗？ 7. Fine, thanks. And you? 很好，谢谢，你呢？ 8. I'm fine, too. 我也很好。 9. How is Amy / your wife / your husband? 爱米好吗？/你妻子好吗？/你丈夫好吗？ 10. She is very well, thank you. 她很好，谢谢。 11. Good night, Jane. 晚安，简。 12. Good-bye, Mike. 再见，迈克。 13. See you tomorrow. 明天见。 14. See you later. 待会儿见。 15. I have to go now. 我必须走了。 二、Expression In Class 课堂用语 16. May I come in? 我能进来吗？ 17. Come in, please. 请进。 18. Sit down, please. 请坐。 19. It's time for class. 上课时间到了。 20. Open your books and turn to page 20. 打开书，翻到第20页。 21. I'll call the roll before class. 课前我要点名。 22. Here! 到！ 23. Has everybody got a sheet? 每个人都拿到材料了吗？ 24. Any different opinion? 有不同意见吗？ 25. Are you with me? 你们跟上我讲的了吗？ 26. Have I made myself clear? 我讲明白了吗？ 27. Could you say it again? 你能再说一遍吗？ 28. Any questions? 有什么问题吗？ 29. That's all for today. 今天就讲到这里。 30. Please turn in your paper before leaving. 请在离开前将论文交上。 三、Identifying Objects 辨别物品 31. What's this? 这是什么？ 32. It's a pen. 是支笔。 33. Is this your handbag? 这是你的手提包吗？ 34. No, it isn't. / Yes, it is. 不，它不是。/是的，它是。 35. Whose pen is this? 这是谁的笔？ 36. It's Kate's. 是凯特的。
《葛底斯堡演讲》三个中文译本的对比分析 葛底斯堡演讲是林肯于19世纪发表的一次演讲,该演讲总长度约3分钟。然而该演讲结构严谨,富有浓郁的感染力和号召力,即便历经两个世纪仍为人们津津乐道,成为美国历史上最有传奇色彩和最富有影响力的演讲之一。本文通过对《葛底斯堡演讲》的三个译本进行比较分析,从而更进一步加深对该演讲的理解。 标签：葛底斯堡演讲,翻译对比分析 葛底斯堡演讲是美国历史上最为人们所熟知的演讲之一。1863年11月19日下午,林肯在葛底斯堡国家烈士公墓的落成仪式上发表献词。该公墓是用以掩埋并缅怀4个半月前在葛底斯堡战役中牺牲的烈士。 林肯是当天的第二位演讲者,经过废寝忘食地精心准备,该演讲语言庄严凝练,内容激昂奋进。在不足三分钟的演讲里,林肯通过引用了美国独立宣言中所倡导的人权平等,赋予了美国内战全新的内涵,内战并不仅是为了盟军而战,更是为了“自由的新生(anewbirthoffreedom)”而战,并号召人们不要让鲜血白流,要继续逝者未竞的事业。林肯的《葛底斯堡演讲》成功地征服了人们,历经多年仍被推崇为举世闻名的演说典范。 一、葛底斯堡演说的创作背景 1.葛底斯堡演说的创作背景 1863年7月1日葛底斯堡战役打响了。战火持续了三天,战况无比惨烈,16万多名士兵在该战役中失去了生命。这场战役后来成为了美国南北战争的一个转折点。而对于这个位于宾夕法尼亚州,人口仅2400人的葛底斯堡小镇,这场战争也带来了巨大的影响——战争遗留下来的士兵尸体多达7500具,战马的尸体几千具,在7月闷热潮湿的空气里,腐化在迅速的蔓延。 能让逝者尽快入土为安,成为该小镇几千户居民的当务之急。小镇本打算购买一片土地用以兴建公墓掩埋战死的士兵,然后再向家属索要丧葬费。然而当地一位富有的律师威尔斯(DavidWills)提出了反对意见,并立即写信给宾夕法尼亚州的州长,提议由他本人出资资助该公墓的兴建,该请求获得了批准。 威尔斯本打算在10月23日邀请当时哈佛大学的校长爱德华(EdwardEverett)来发表献词。爱德华是当时一名享有盛誉的著名演讲者。爱德华回信告知威尔斯,说他无法在那么短的时间之内准备好演讲,并要求延期。因此,威尔斯便将公墓落成仪式延期至该年的11月19日。 相比较威尔斯对爱德华的盛情邀请,林肯接到的邀请显然就怠慢很多了。首先,林肯是在公墓落成仪式前17天才收到邀请。根据十九世纪的标准,仅提前17天才邀请总统参加某一项活动是极其仓促的。而威尔斯的邀请信也充满了怠慢,
跨文化沟通 姓名：楚辰玺学号：15120299 案例的选择是一个叫做万里的土耳其学生，是我同学的好朋友，所以平时也有接触。他在中国呆了一年，然后走了，现在又在波兰求学。原来我问他说，为什么要离开中国呢。因他是一个熟练掌握七种语言的人，所以我很佩服他。也很不解。他说因为感觉在中国的生活很难受，感觉自己时时刻刻都很委屈。 后来他给我举了个例子，比如他问中国同学，你想要些什么，或者，你会争取奖学金么，或者是他作为领导问自己的手下，你的目标是什么。而以上种种给他的回答大多是摸棱两可，不置可否。后来我通过《跨文化沟通》一书中的高低语境解答了我的困惑。他的本意只是直来直去，比如他只是想知道自己的手下想要到达一个怎么的高度，或者有什么目标。但是他很直白，不含蓄。所以属于低语境的对话，而中国的文化，众所周知，属于高语境文化，是比较含蓄，委婉。他在这样的环境中会觉得自己是被排挤，被隐瞒的一方，觉得中国的人们不够坦诚，给他的印象很不好。i 我问他对于直接询问、回答和间接的委婉的询问和回答在他看来有什么区别，也就是我们所说的高语境文化和低语境文化。他说为什么不直接说呢？他表示不解，觉得即使说错了或者有冒犯也会得到原谅，不会为人们在意。我觉得这里有着中外文化交流之间冲突的一个矛盾点，中式的对话和交流相处在高语境文化下的重要因素是害怕受到惩罚，或者说有规则的舒服，也就是万里经常说的不自由，我认为是谨小慎微，超出了谨慎的程度，成为了一种惯例。 为了了解外国人与中国人的对话，我要了几张他和中国朋友的对话截图。因为万里是去过三个大洲，25个国家，他像我的朋友发出邀请，说一起去欧洲，我朋友是个女生，然后他说可以住在他家里。当时我还记得我朋友的男朋友很不开心。所以对于在我看来他们的思想和行为都是很自由的。他们更注重个人的发展，而不是集体主义。这个论据的寻求在BBC 的一个纪录片《中国老师来了》。着重体现了英国的教育制度与中国传统的教学制度的不同，比如对于纪律的要求，对于整齐划一的广播操的要求。都体现了在中国的教育体制传输的一种集体主义思想。 他们自己会更注重自己个人的发展，比如万里不舒服就很毅然的离开，他对这里的环境虽有眷恋但是并不可以影响自己的追求，还有他去过25个国家，对于自己的国家也没有很强烈的集体主义感。对于个人的发展要求和对自己的愿望的实现更迫切一些，对于一些对于个人无意义的比如集体的跑操活动，还有课堂上的一些硬性要求，为了培养中国学生的整齐划一的执行能力和集体主义的归属感。 在我咨询万里为什么离开中国，他的陈述中有一个高频词汇“自由”，他认为在中国的各种生活都不自由，在他看来，是一种思想自由和行为自由的不想当。他的想法中，除了早操还有固定的上课模式、固定的强制参加的活动、对于体测的要求等等。 而且在我对于所看到聊天记录的分析，他是一个很会适应当地的生活习俗的人，比如节日，前几天，十二月三十一号晚上，他给我的朋友发了元旦快乐。当时的对话是这样的。万里说：“新年快乐”我的朋友W说：“万里！新年快乐!你那里几点了。我这里11:41了。”万里说：“这里还是四点多，还有很长时间，但在中国已经新年了。”W说：“你能想到我，我很开心的。”万里：“嗯，当然想到你。我们是朋友。”加重语气又说：“好朋友。”这里的好朋友三个字引人深思，我朋友和他的交流的时间并不长，也是之前上过一节课，然后在一个小组，所以有了一定的交流。 在这里我想起上课时结合教材老师讲到的，外国学生对于在学校交流的伙伴，在课后就不管不顾不问候，所以这里有些许的疑问，所以我在询问他，是否真的是这样，对于你们在课
英语口语20个对话主题 英语口语对话主题（001）相貌 A: That girl looks very attractive, doesn’t she? B: do you think so? I don’t like girls who look like that. I like girls who aren’t too slim. If you like her, go and talk to her. A: I’d like to, but there’s her boyfriend. He’s very broad-shouldered. B: he’s huge! He must go to the gym to have a well-built body like that. A: do you prefer tall girls or short ones? B: I don’t mind, but I like girls with long hair. A: we have different tastes. I like girls with short hair. I like tall girls- probably because I’m so tall myself. B: have you ever dated a girl taller than you? A: no, never. I don’t think I’ve ever met a girl taller than me! Have you gained weight recently? B: yes, I have. Perhaps I should go to the gym, like t hat girl’s boyfriend. A: I ‘m getting a bit plump myself. Perhaps I’ll go with you. 英语口语对话主题（002）身体部分 A: I’m going to the beauty parlor. Do you want to come too? B: sure. Let’s go. What are you going to have done? A: I want to have a foot massage and haircut. B: a foot massage sounds like a great idea. They are very relaxing. I’d also like to have a mudpack on my face. It’s supposed to help with your complexion. A: good idea. We should also pedicures and manicures. B: this could become a very expensive trip to be beauty parlour! A: I think it’s a good idea to pamper yourself occasionally. Don’t you agree? B: oh, I agree. We both work hard and a little beauty treatment can relieve stress. A: maybe we should try a thai massage too. B: what’s specia l about a thai massage? A: that’s when the masseuse walk on your back and massage you with her feet. B: sounds painful! 英语口语对话主题（003）身体部位的运动 A: when you are in a restaurant you want the waiter to bring the bill, what do you do to attract his attention? B: I just make eye contact with him and nod my head. Then I tell him when he comes over to the table. Why do you ask? A: I went out with my girlfriend to a nice restaurant last night and I noticed that many people shouted for the bill.
《跨文化沟通》情景剧 第一幕 时间：早上 地点：某跨国公司会客大厅 人物：跨国公司子公司负责人——A日本人（饰演者：） B美国人（饰演者：） C中国人（饰演者：） D阿拉伯人（饰演者：） E泰国人（饰演者：） F英国人总裁（饰演者：） G接引日本人（饰演者：） — （旁白）某跨国大公司出现大危机，来自各国分公司的负责人纷纷赶回英国到总 部会面进行商务会谈。会谈时间定为早上9点， 现在是8点30分。 （CEO坐在办公室，一边批阅文件，一边等待其他子公司的负责人到来） 接引日本人：（“咚咚咚”敲门后开门）先生，有一部分子公司负责人已经到达会 场了。 英国人总裁：好的，谢谢，我这就过去。 接引日本人：（深深鞠躬后，退出办公室，并小声地关上门。） （旁白）此时，各子公司的负责人相继进入会场。 美国人B：（热情地走向第一个到达的日本人A，伸出手）你好，第一次见面。
日本人A：（朝向美国人B，弯腰鞠躬）阁下，你好，请多指教。 美国人B：（手悬在空中，略显尴尬）你好，你好。 日本人A：（见此状，连忙握手）抱歉，先生，实在抱歉。请多指教。（又弯腰鞠躬 一次） 阿拉伯人D：（D进入的同时E也到了，D看见老朋友E，高兴地到E面前，右手扶 住对方的左肩，左手搂抱对方腰部，然后，按 照先左后右的顺序，贴面三次，即左——右—— 左。在贴面的同时）艾赫兰——艾赫兰——艾 赫兰（即“你好”）最近怎么样啊！（后嘴里发 出亲吻的声音） 】 泰国人E：（虽然习惯了，但还是表现出很无奈的样子，后双手合十，举于胸前， 朝向三人，面带微笑）萨瓦滴卡。（转过身面向 D）还好，这把老骨头还能在商场战几年，哈哈 哈。 阿拉伯D：（D搂着E，朝向A、B也热情地迎上去，伸手）（“你好”）你们那边还 好吗 日本人A：（握手）你好啊。我还好。公司还能正常运转。 阿拉伯人D说话时眼睛紧紧盯着日本人A的眼睛，这让日本人A很不自在，很勉 强地看了一眼阿拉伯人，就把头低了下去。 美国人B：（握手）你好，阁下。我们这次来不就是为了让它变得更好吗 中国人C：（看了看手表，嘀咕了一句“还好只是迟到了一点点”后，整理整理服 装进入会场）抱歉，各位，你们好，我来晚了。
P4外在文化：外在文化指文化外显的一面,是可以感知、识别的,或可通过文字记载而获得，一切文化现象，即包括文化行为在内的各种文化事、物，都属于外在文化。 P4内在文化：内在文化指文化内隐的面，从文字记载中不能直接感知和识别，包括人们作出决定、完成任务、衡量事物的重要性和把知识概念化的方式以及怎样对于种种限制作出反应。 P4交互性文化：在沟通的平台上，双方都能对彼此言行中的文化暗示做出反应，并且以此来修正自己的行为，这样就形成了一种交互性文化。 P6文化：文化是群体成员连贯一致的、后天习得的、群体共享的观念，人们藉此决定事情的轻重缓急，就事情的适宜性表明自己的态度，并决定和支配后续的行为。 文化的三个特点： 1、连贯一致的：每一种文化，不管是，去的还是现在的，都具有一致性和完整性，即文化也是一种完整的宇宙观，如果群体成员从自己狭隘的宇宙观出发，就很有可能看不到在自己“统一的、持久的愿景”中所缺少的东西； 2、后天习得的：文化并不是天生的，而是通过学习掌握的。同样如果要了解其他文化，就要通过学习来掌握，不只是浅尝辄止，而要深入学习，并按其行为准则来规范自己的行为； 3、群体共享的观念：文化是为社会所共享的。社会成员在事物的含义的以及这种含义的归因上达成了共识。社会被共同的价值观所驱动，同一文化背景中的人员共享该文化的各种符号、标识。 文化的三个功能： 1、文化决定事情的轻重缓急。 2、文化决定态度，态度是通过学习而形成的，它是对事物的总体评价 3、文化支配行为，人们的行为直接受到价值观的支配，直接来源于对事物价值的判断 P16文化休克：文化休克指的是在一段时间里出现的一系列反应，是一种混乱感、一种心理甚至是生理上的问题，这些问题都是源于在其它文化中求生的欲望引发调整和改变自己的努力所带来的压力。 P18反文化休克：旅居国外的人回到祖国以后，常常会出现一段与在国外相似的调整和适应期，以及伴随而来的一些类似的症状。 P24刻板印象：当我们面对陌生的或者复杂的事物时，我们对其产生的固定的，僵化的印象。P27文化智力：一个人成功地适应新文化环境的能力。 P30跨文化沟通：通常是指不同文化背景的人之间发生的沟通行为。因为地域不同、种族不同等因素导致文化差异，因此，跨文化沟通可能发生在国际间，也能发生在不同的文化群体之间。 问题二P32高语境文化：，有较多的信息量由情景而不是语言方式来进行传达。特点：晦涩的，间接的，暗指的 低语境文化：大多数信息都是通过外在的语言方式来进行传达。特点：明确的，直接的，完全用词语表达 P36 问题三P43语言文化的关系：语言与文化的关系：语言与文化相互交织在一起，相互影响，密不可分。语言能够帮助我们同不同文化背景的人进行沟通，文化认知对语言的运用也十分必要。 1、语言反映环境，语言可以折射出我们的生活环境，我们用语言描述身边的事物。（如“雪”）同时环境影响词汇的发展； 2、语言体现价值观，在与来自其他文化背景的人沟通时，我们要把异国语言文化中的概念用适合国人价值观排序的方式准确翻译出来。进行思想沟通，文化知识与语言知识是同等重
（一）典型案例： 飞利浦照明公司某区人力资源的一名美国籍副总裁与一位被认为具有发展潜力的中国员工交谈。他很想听听这位员工对自己今后五年的职业发展规划以及期望达到的位置。中国员工并没有正面回答问题，而是开始谈论起公司未来的发展方向、公司的晋升体系，以及目前他本人在组织中的位置等等，说了半天也没有正面回答副总裁的问题。副总裁有些疑惑不解，没等他说完已经不耐烦了。同样的事情之前已经发生了好几次。 谈话结束后，副总裁忍不住想人力资源总监抱怨道：“我不过是想知道这位员工对于自己未来五年发展的打算，想要在飞利浦做到什么样的职位而已，可为什么就不能得到明确的回答呢？”“这位老外总裁怎么这样咄咄逼人？”谈话中受到压力的员工也向人力资源总监诉苦。 （二）案例中的文化差异对沟通产生的影响分析 在该案例中，副总裁是美国籍人，而那位员工则是中国籍。显然，对于出生于两个不同的国度的人，中美之间思维方式、生活习惯、文化背景、教育程度、文化差异等多个方面都存在着显著的差异。正是由于这些文化差异的存在，才使得双方在沟通交流的过程中产生一系列障碍。 案例中“中国员工并没有正面回答问题”，原因可能是多种多样的。 （１）语言障碍、没有理解透彻美国副总裁所说话语的原意。 中文和英文之间存在很大的差异，在我们学习英文的过程中我们可以体会到，对于一个中国人，要完全体会英文背后的文化是很困难的一件事。例如，“pull one's leg”本意是“开玩笑”，但我们很容易就理解成“拉后腿”的意思了。 （２）思维方式明显不相同。 假设这位中国员工从正面直接回答了副总的问题。比如，中国员工回答：“……想在五年之内作到营销部经理的职位。”很显然，按照中国人的传统心理，这样的回答违反了中国人一向谦虚、委婉的心理习惯。太直接反而暴露出自己很有野心，高傲自大的缺陷。谦虚也可以给自己留有后路，万一做不到那个理想的位子，也不至于丢面子，被人耻笑。恰恰相反，美国人一向简单明了，很直接，这也是他们一贯的思维方式。
《跨文化沟通》考点整理 一、名词解释 1．外在文化 2．内在文化 3．交易性文化 4．文化 5．高语境文化 6．低语境文化 7．个人主义 8．集体主义 9．权力距离 10．不确定性规避 11．不确定性容忍 12．男性化 13．女性化 14．副语言 15．空间语言 二、论述题及简答题考点 1．文化的三个特点（连贯一致、后天习得、群体共享）及三个功能（决定事情的轻重缓急、政治因素就事情的适宜性表明自己的态度、决定和支配后续的行为）P4~8 2．高语境文化与低语境文化P19~20 3．语言反映环境P28~29 4．语言体现价值观P29 5．如何选择正确的语言（语言因素、商业因素、、适当的流利程度）P32~35 6．五个范畴（结合小结P72~73、P91重点复习） 7．副语言P120~121 8．在面对面沟通中的非言语行为习惯（七个方面，重点看“口头沟通中的话语权”、“空间语言”、“沉默”三个部分，注意区分不同文化差异的行为习惯P121~137） 9．如何表达尊重：权势地位、服饰作为权威的象征P140~142 10．绩效奖励P150~152 11．界定问题并解决问题（注意高低语境文化与集体主义和个人主义方面的差异阐述）P176~177 12．冲突管理（注意高低语境文化与集体主义和个人主义方面的的不同理解以及低语境文化对冲突管理方法的排次）P177~180 13．冲突沟通的策略（五点）P180~182 14．谈判要素（四个方面）P190~199 15．谈判的阶段划分（四个阶段）P200~205 《跨文化沟通》论述题及简答题语言归纳 1．文化的三个特点（连贯一致、后天习得、群体共享）及三个功能（决定事情的轻重缓急、就事情的适宜性表明自己的态度、决定和支配后续的行为）P4~8 文化的三个特点：
1 What are your long range and short range goals and objectives, when and why did you establish these goals and how are you preparing yourself to achieve them? 你的长期目标和短期目标是什么?你什么时候、为什么确立这些目标?你是如何为实现这些目标做准备的? The long-term goal is to enter the management level after work, establish my own working team, plan and complete specific projects independently, and create more wealth for the company and individual. In order to achieve it my short-term goal is to gain working experience.Learn all kinds of basic professional skills and be able to skillfully use them. Obtain certificates and improve interpersonal skills .I have set these goals since I entered the university, because I want to be a useful person, who can support myself, honor my parents and give back to the society.长期目标是希望工作后能进入管理层，组建自己的工作团队，独立策划完成具体的项目，为公司和个人创造更多的财富。为了实现它，我的短期目标是学习各种基本职业技能并能熟练运用，考取证书，提高人际交往能力。从我刚进入大学的时候我就确立了这些目标，是因为我想成为一个有用的人，能养活自己，孝敬父母，回报社会。 2 What do you see yourself doing five years from now? 你认为五年后你自己会做什么? I entered the management level, established my own working team, planned and completed specific projects independently, and created more wealth for the company and individuals. 能进入管理层，组建自己的工作团队，独立策划完成具体的项目，为公司和个人创造更多的财富。 3 What are your long-range career objectives? 你的长期职业目标是什么? I entered the management level, established my own working team, planned and completed specific projects independently, and created more wealth for the company and individuals. 能进入管理层，组建自己的工作团队，独立策划完成具体的项目，为公司和个人创造更多的财富。 4 How do you plan to achieve your career goals? 你打算如何实现你的职业目标? In order to achieve my career goals, I think the answer is performance.If I can perform well in my current position, I will naturally win the trust of the management team and enter the next stage of my career.So, what I should do is to work hard and get good grades in my work.为了实现我的职业目标,我认为答案是绩效。如果我能在目前的岗位上表现出色，我自然会赢得管理团队的信任，并进入职业生涯的下一个阶段。所以，我要做的就是努力工作，在工作中取得好成绩。 5 Why did you choose the career for which you are preparing? 你为什么选择了你正在准备的职业? I really like the job description and the working duties on this position .And I can do a good job in this position.because My major, knowledge, ability and specialty are in line with the job requirements of this position.I think I will get a sense of accomplishment from the work of this position and grow rapidly. 我非常喜欢这个职位的工作描述和工作职责，我能做好这个职位。因为我的专业、知识、能力和专业都符合这个职位的工作要求。我觉得自己一定能从这个职位的工作中获得成就感，
话说宝玉在林黛玉房中说"耗子精"，宝钗撞来，讽刺宝玉元宵不知"绿蜡"之典，三人正在房中互相讥刺取笑。 杨宪益：Pao-yu，as we saw, was in Tai-yu?s room telling her the story about the rat spirits when Pao-chai burst in and teased him for forgetting the “green wax” allusion on the night of the Feast of Lanterns. 霍克斯: We have shown how Bao-yu was in Dai-yu?s room telling her the story of the magic mice; how Bao-Chai burst in on them and twitted Bao-yu with his failure to remember the …green wax? allusion on the night of the Lantern Festival; and how the three of them sat teasing each other with good-humored banter. 对比分析：杨宪益和霍克斯在翻译“耗子精”采用来了不同的处理方法，前者使用了异化”rat spirits”，后者用的是归化法”magic mice”,使用归化法更受英美读者的亲乃。但是二者同时采用了增译法，增添了the story，原文并没有。在翻译“宝玉不知绿烛之典”的“不知”，英文1用的是“forgetting”，而译文2用的是“with failure to ”，显然译文2更符合英美的表达习惯。 那宝玉正恐黛玉饭后贪眠，一时存了食，或夜间走了困，皆非保养身体之法。幸而宝钗走来，大家谈笑，那林黛玉方不欲睡，自己才放了心。 杨宪益：Pao-yu felt relieved as they laughed and made fun of each other, for he had feared that sleeping after lunch might give Tai-yu indigestion or insomnia that night, and so injure her health. Luckily Pao-chai?s arrival and the lively conversation that followed it had woken Tai-yu up. 霍克斯: Bao-yu had been afraid that by sleeping after her meal Dai-yu would give herself indigestion or suffer from insomnia through being insufficiently tired when she went to bed at night, but Bao-chai?s arrival and the lively conversation that followed it banished all Dai-yu?s desire to sleep and enabled him to lay aside his anxiety on her behalf. 对比分析：译文一对原文语序进行了调整，先说了“放心”，再说“担心”，但并不如不调整顺序的逻辑强。译文二只是用了一个“but”就把原文意思分层了两层，逻辑更加清晰，符合西方人注重逻辑的习惯。原文中的“谈笑”是动词，而两个译文版本都是译的“the lively conversation”，是名词，体现了汉语重动态，英文重静态的特点。 忽听他房中嚷起来，大家侧耳听了一听，林黛玉先笑道："这是你妈妈和袭人叫嚷呢。那袭人也罢了，你妈妈再要认真排场她，可见老背晦了。" 杨宪益：Just then, a commotion broke out in Pao-yu?s apartments and three of th em pricked up their ears. “It?s your nanny scolding Hai-jen,” announced Tai-yu. “There?s nothing wrong with Hai-jen, yet your nanny is for ever nagging at her. Old age has befuddled her.”
《傲慢与偏见》（节选一） Pride and Prejudice by Jane Austen (An Except from Chapter One) 译文对比分析 节选文章背景：小乡绅贝内特有五个待字闺中的千金，贝内特太太整天操心着为女儿物色称心如意的丈夫。新来的邻居宾利(Bingley)是个有钱的单身汉，他立即成了贝内特太太追猎的目标。 1.It’s a truth u niversally acknowledged, that a single man in possession of a good fortune, must be in want of a wife. 译文一：凡是有钱的单身汉，总想娶位太太，这已经成了一条举世公认的道理。译文二：有钱的单身汉总要娶位太太，这是一条举世公认的真理。 2.However little known the feelings or views of such a man may be on his first entering a neighborhood, this truth is so well fixed in the minds of the surrounding families that he is considered as the rightful property of some one or other of their daughters. 译文一：这样的单身汉，每逢新搬到一个地方，四邻八舍虽然完全不了解他的性情如何，见解如何，可是，既然这样的一条真理早已在人们心中根深蒂固，因此人们总是把他看作是自己某一个女儿理所应得的一笔财产。 译文二：这条真理还真够深入人心的，每逢这样的单身汉新搬到一个地方，四邻八舍的人家尽管对他的性情见识一无所知，却把他视为某一个女儿的合法财产。 3.”My dear Mr. benne” said his lady to him one day ,”have you heard that nether field park is let at last?” 译文一：有一天班纳特太太对她的丈夫说：“我的好老爷，尼日斐花园终于租出去了，你听说过没有？” 译文二：“亲爱的贝特先生”一天，贝纳特太太对先生说：“你有没有听说内瑟费尔德庄园终于租出去了：” 4.Mr. Bennet replied that he had not. 译文一：纳特先生回答道，他没有听说过。 译文二：纳特先生回答道，没有听说过。 5.”But it is,” returned she:” for Mrs. long has just been here, and she t old me all about it.” 译文一：“的确租出去了，”她说，“朗格太太刚刚上这来过，她把这件事情的底细，一五一十地都告诉了我。” 译文二：“的确租出去了，”太太说道。“朗太太刚刚来过，她把这事一五一十地全告诉我了。”