Chapter1ThermodynamicsandHeatTransfer
主要内容
ts:
heat(thermalenergy)、heattransfer、thermodynamics、total
amountofheattransfer、heattransferrate、heatflux、
conduction、convection、radiation
ons:
1)Thefirstlawofthermodynamics(conrvationofenergy
principle)
2)Heatbalanceequation:a)clodsystem;b)open
system(steady-flow)
3)Fourier’slawofheatconduction
4)Newton’slawofcooling
5)Stefan-Boltzmannlaw
主要专业词汇
heattransfer传热、热传递、传热学thermodynamics热力
学
caloric热素specificheat比热massflowrate质量
流率
latentheat潜热nsibleheat显热heatflux热流
密度
heattransferrate热流量totalamountofheattransfer总热
量
conduction导热convection对流radiation辐
射
thermalconductivity热导率thermaldiffusivity热扩散
率
convection/combinedheattransfercoefficient对流/综合换热
系数
emissivity发射率absorptivity吸收
率
simultaneousheattransfer复合换热
Chapter2HeatConductionEquation
主要内容
ts:
temperaturefield、temperaturegradient、heatgeneration、initial
condition、boundarycondition、steadytransientheattransfer、
uniformnonuniformtemperaturedistribution
ons:
1)Fourier’slawofheatconduction(§2-1)
2)Heatconductionequation(in
rectangularcylindricalsphericalcoordinates)
(§2-2、§2-3)
3)Boundaryconditions:(§2-4)
a)SpecifiedtemperatureB.C.
b)SpecifiedheatfluxB.C.[specialca(dt/dx=0):
insulation、thermalsymmetry];
c)ConvectionB.C.
d)RadiationB.C.
e)InterfaceB.C.
4)Averagethermalconductivitykave(§2-7)
5)Solutionofone-dimensional,steadyheatconductionin
planewalls、cylindersandspheres(k=const):
a)noheatgeneration,specifiedB.C.:T(x)orT(r)
(§2-5)
Q(x)orQ(r),Q=const
b)withheatgeneration,ectionB.C.:
(§2-6)
∆Tmax=To-Ts=gs2/2nk;q(x)=gx/n;Ts=T+gs/nh
characteristiclengthS,shapefactorn:
planewalls—s=L(halfthickness),n=1
cylinders——s=ro
,n=2
spheres——s=ro
,n=3
s:Solveaheattransferproblem
1)Mathematicalformulation(differentialequation&B.C.)
2)Generalsolutionofequation
3)ApplicationofB.C.s
4)Uniquesolutionoftheproblem
主要专业词汇
temperaturefielddistribution温度场分布temperature
gradient温度梯度
heatgeneration热生成(热源)initialboundarycondition初始
边界条件
transientheattransfer瞬态(非稳态)传热isothermal
surface等温面
Heatconductiondifferentialequation导热微分方程
trialanderrormethod试算法iterate迭代
convergence收敛
Chapter3SteadyHeatConduction
主要内容
ts:
multilayercompositewalloverallheattransfercoefficientU
thermalresistanceRt
thermalcontactresistanceRc
criticalradiusof
insulationRcr
finefficiencyfineffectiveness
ons:
✓Multiplayerplanewall、cylindersandspheres:
✓Fin:finequation——refertotheattachment.
1)Uniformcross-ction:refertotheattachment.
2)Varyingcross-ction:refertotheattachment.
主要专业词汇
thermalresistance热阻parallel并联inries串
联
thermalcontactresistance接触热阻compositewall复合壁
面
thermalgrea热脂cross-ction横截面temperatureexecess
过余温度
hyperbolic双曲线的exponent指数
fin肋(翅)片finba肋基fintip肋端
finefficiency肋效率fineffectiveness肋片有效度
Chapter4TransientHeatConduction
主要内容
ts:
lumpedsystemanalysischaracteristiclength(L
c
=V/A)
Biotnumber(Bi=hL
c
/k)Fouriernumber(τ=at/L)
ons:
Bi≤0,lumpedsystemanalysis(§4-1)
Bi>0,Heisler/GroberchartsORanalyticalexpressions
1-D:a)infinitelargeplanewalls,longcylindersandspheres(§
4-2)
b)mi-infinitesolids(§4-3)
multidimensional:productsolution(§4-4)
主要专业词汇
lumpedsystemanalysis集总参数法characteristiclength特征长度(尺寸)
dimension量纲nondimensionalize无量纲化dimensionlessquantity无量纲量
mi-infinitesolid半无限大固体complementaryerrorfunction误差余函数
ries级数productionsolution乘积解
Chapter5NumericalMethodsinHeatConduction
主要内容
ts:
controlvolume(energybalance)method、finitedifferencemethod、
discretization、node、spacestep、timestep、
meshBiotnumber、meshFouriernumber、mirrorimageconcept、
explicit/implicitmethod、stabilitycriterion(primarycoefficients0)
Numericalerror:1)discretization/truncationerror;2)round-offerror
s:
Numericalsolution:
1)Discretizationinspaceandtime(x,t);
2)Buildallnodes’finitedifferenceformulations(includinginteriorand
boundarynodes);
differencemethod
balancemethod(i.e.
ControlVolumemethod)
3)conduction;
method:GaussianElimination
ivemethod:Gauss-Seideliteration
主要专业词汇
controlvolume控制容积finitedifference有限差分
Taylorriexpression泰勒级数展开式
mirrorimageconcept镜像法Eliminationmethod消元法
direct/iterativemethod直接/迭代方法explicit/implicitmethod显式/隐式格式
stabilitycriterion稳定性条件primarycoefficients主系数
unconditionally无条件地algebraiceq.代数方程
discretization/truncationerror离散/截断误差round-offerror舍入误差
Chapter6、7ForcedConvectionandNatural
Convection
主要内容
ts:
Nu、Re、Gr、Pr
Force/naturalconvection、external/internalflow、velocity/thermalboundarylayer
flowregimes、laminar/turbulentflow
hydrodynamic/thermalentryregion、fullydevelopedregion
CriticalReynoldsNumber(Re
c
)、hydraulicdiameter(D
h
)、
filmtemperature(T
f
)、bulkmeanfluidtemperature(T
b
)
logarithmicmeantemperaturedifference(T
ln
)
volumeexpansioncoefficient(β=1/T)
effectivethermalconductivity(Keff
=KNu)
ons:
Dragforce:FD
=CfAρV2/2
Heattransferrate:Q=hA(Ts-T)
3.TypicalConvectionPhenomena:
1)Forcedconvection:externalflow——flowoverflatplates(§6-4)
——flowacrosscylindersandspheres(§6-5)
internalflow——flowintubes(§6-6)
2)Naturalconvection:flowoversurfaces(§7-2)
flowinsideenclosures(§7-3)
主要专业词汇
Force/naturalconvection自然/强制对流laminar/turbulentflow层/湍流
boundarylayer边界层laminarsublayer层流底层bufferlayer缓冲层
transitionregion过渡区flowregimes流态
inertia/viscousforce惯性/粘性力shearstress剪切应力
friction/dragcoefficient摩擦/阻力系数frictionfactor摩擦因子
dynamic/kinematicviscous动力/运动粘度
wake尾流stagnationpoint滞止点flowparation流体分离
vortex漩涡rotationalmotion环流velocityfluctuation速度脉动
hydrodynamic水动力学的hydraulicdiameter水力直径
fullydevelopedregion充分发展段volumeflowrate体积流量
arithmetic/logarithmicmeantemperaturedifference算术/对数平均温差
volumeexpansioncoefficient体积膨胀系数
interferometer干涉仪asymptotic渐近线的
effectivethermalconductivity有效热导率
analogicalmethod类比法integralapproach积分近似法
orderofmagnitudeanalysis数量级分析法similarityprinciple相似原理
Chapter9RadiationHeatTransfer
主要内容
ts:
blackbody、graybody、diffusurface、emissivepower(E)
emissivity(ε)、absorptivity(α)、reflectivity(ρ)、transmissivity(τ)
irradiation(G)、radiosity(J)、reradiating(adiabatic)surface
viewfactor(Fij
)、radiationnetwork、spaceresistance、surfaceresistance
radiationshield
gasradiation、transparentmediumtoradiation、absorbingandtransmitting
medium
:
Blackbody:(1)Plank’slaw
(2)Stefan-Boltzmann’slaw
(3)Wien’sdisplacementlaw
Graybody:(4)Kirchhoff’slaw
Actualbody:E(T)=εEb
(T)=εσT4W/m2
Gas:(5)Beer’slaw
3.Calculation:
1)Viewfactor:reciprocity/summation/superposition/symmetryRule
crosd-stringsmethod
2)Radiationheattransfer:Radiationnetwork
Opensystem:betweentwosurface(geparallelplates)
Enclosure:2-surfaceenclosure;3-surfaceenclosure
Radiationshield
主要专业词汇
thermalradiation热辐射、quantumtheory量子理论、indexofrefraction折射
系数
electromagneticwave/spectrum电磁波/波谱、ultraviolet(UV)rays紫外线、
infrared(IR)rays红外线
absorptivity吸收率、reflectivity反射率、transmissivity透射率、emissivity(ε)
发射率(黑度)、specular/diffureflection镜反射/漫反射
irradiation(incidentradiation)投入辐射、radiosity有效辐射
spectral/directional/totalemissivepower单色/定向/总辐射力
fractionofradiationenergy辐射能量份额(辐射比)、blackbodyradiation
function黑体辐射函数
viewfactor辐射角系数、crosd-stringsmethod交叉线法、
reciprocity/summation/superposition/symmetryRule相互/完整/和分/对称性
netradiationheattransfer净辐射热流量
radiationnetwork辐射网络图、space/surfaceradiationresistance空间/表面辐
射热阻、
reradiatingsurface重辐射面、adiabatic绝热的
radiationshield遮热板
transparentmediumtoradiation辐射透热体、absorbingandtransmittingmedium吸收-透过性介
质
Chapter10HeatExchangers
主要内容
ts:
heatexchangertype----double-pipe、compact、shell-and-tube、
plate-and-frame、regenerativeheatexchanger
parallel/counter/cross/multipassflow
overallheattransfercoefficient(U)foulingfactor(Rf
)
heatcapacityratecapacityration
logmeantemperaturedifference(ΔTlm
)
heattransfereffectiveness(ε)
numberoftransferunits(NTU)
ons:
1)heatbalanceeq.:Q=C
h
(Th,in
-Th,out
)=Cc
(Tc,out
-Tc,in
)
2)heattransfereq.:Q=UAΔTlm
(LMTDmethod)
orQ=εQmax
=εCmin
(Th,in
?CTc,in
)(ε-NTUmethod)
3.Methods:
1)LMTDMethod:lectaheatexchanger
Known:Ch
、Cc
、3‘T’
Predict:1‘T’、Q、A
2)ε-NTUMethod:evaluatetheperformanceofaspecifiedheatexchanger
Known:Ch
、Cc
、UA、Th,in
、Tc,in
Predict:Q、Th,out
、Tc,out
主要专业词汇
double-pipe/compact/shell-and-tube/plate-and-frame/regenerativeheat
exchanger
套管式/紧凑式/壳管式/板式/蓄热(再生)式换热器
parallel/counter/cross/multipassflow顺流/逆流/叉流/多程流
areadensity面积密度tube/shellpass管程/壳程static/dynamictype静/动
态型
baffle挡板header封头nozzle管嘴guidebar导向杆porthole孔口
gasket垫圈lateral侧面的/横向的
foulingfactor污垢因子heatcapacityrate水当量
heattransfereffectiveness(ε)传热有效度
numberoftransferunits(NTU)传热单元数
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