Adrian Bejan(Editor), Allan D. Kraus (Editor). Heat transfer Handbok (776115), страница 79
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(6.171), dimensionlessReynolds number based on diameter, dimensionlessReynolds number at maximum flow, dimensionlessroughness Reynolds number, dimensionlessReynolds number based on length, dimensionlessReynolds number defined by eq. (6.173), dimensionlessReynolds number based on Ph defined in Section 6.6.2,dimensionlessReynolds number based on P defined in Section 6.6.2,dimensionlesscritical Reynolds number, dimensionlessReynolds number based on x, dimensionlesstransition Reynolds number, dimensionlessboundary layer ratio, dimensionlessrecovery factor, dimensionlessdistance from axis to surface, mjet spacing, mdiagonal tube spacing, mlongitudinal tube spacing, mtransverse tube spacing, mStanton number, dimensionlessroughness Stanton number, dimensionlessBOOKCOMP, Inc. — John Wiley & Sons / Page 518 / 2nd Proofs / Heat Transfer Handbook / Bejan[518], (80)Lines: 3613 to 3613———0.00577pt PgVar———Normal PagePgEnds: TEX[518], (80)NOMENCLATURE123456789101112131415161718192021222324252627282930313233343536373839404142434445ssxszTT̄T̄sTair,BTbTmaxTrefTsTs,BT∗Tb+T0T∞tt∗t0UU∞U0Ucuu+u+∞uoūu∗VVmaxVvv0v∗v+v̄strip spacing, mclear space between blocks, mx-coordinate distance, mdistance to bounding surface, mtemperature, Kaverage or mean temperature, Kaverage surface temperature, Ktemperature of air at block B, Ktemperature in buffer region, Ktemperature at bottom surface of heat sink, Kmaximum surface temperature, Kreference temperature, Ksurface temperature, Ksurface temperature of block B, Knormalized temperature in eq.
(6.8), dimensionlessnormalized buffer temperature, Kfree stream temperature, Kair temperature at front of heat sink, Kambient temperature, Ktime, splate thickness, mnondimensional substrate thickness, dimensionlessnormalized time, stime reference, soverall heat transfer coefficient, W/m2 · Kvelocity scale factor, m/sfree stream velocity, m/svelocity in undisturbed flow, m/saverage velocity in unobstructed channel, m/score velocity, m/sx-coordinate velocity, m/snormalized x-coordinate velocity, m/snormalized free stream x-coordinate velocity, m/sfree stream x-coordinate velocity, m/smean or average x-coordinate velocity, m/snormalized x-coordinate velocity, m/svelocity, m/smaximum velocity, m/svelocity vector, m/sy-coordinate velocity, m/sfree stream y-coordinate velocity, m/sfriction velocity in turbulent flow, m/snormalized y-coordinate velocity, m/smean or average y-coordinate velocity, m/sBOOKCOMP, Inc.
— John Wiley & Sons / Page 519 / 2nd Proofs / Heat Transfer Handbook / Bejan519[519], (81)Lines: 3613 to 3613———0.92038pt PgVar———Normal PagePgEnds: TEX[519], (81)520123456789101112131415161718192021222324252627282930313233343536373839404142434445FORCED CONVECTION: EXTERNAL FLOWSWww∗Xx0xx∗xsYy∗z∗∆p∆pcore∆Tenvelope width, mchannel width, mwidth, mz-coordinate velocity, m/sslot jet width, mnormalized, z-coordinate velocity, m/sbody force, Nx coordinate, munheated starting length, mnormalized x-coordinate velocity, m/sleading edge to heat source distance, mbody force, Nnormalized y-coordinate velocity, m/snormalized z-coordinate velocity, m/spressure difference, N/m2core pressure difference, N/m2temperature difference, KGreek Letter Symbolsαthermal diffusivity, m2/saspect ratio, dimensionlessβvolumetric expansion coefficient, K−1wedge angle, radconstant, pressure difference, N/m2Γgamma function, dimensionless∆change in, dimensionlessδhydrodynamic boundary layer, mmomentum thickness, mδ2conduction thickness, mδcthermal boundary layer, mδTeddy viscosity, m2/seddy diffusivity, m2/sHηsimilarity variable, dimensionlesssimilarity function, dimensionlessBlasius similarity variable, dimensionlessηBthickness of boundary layer, dimensionlessηδθnormalized temperature, dimensionlessangle, radeffect of heat dissipation from block B on block A, K/WθB/Acontribution of all blocks upstream of block B, K/WθB/(i,j )hot spot temperature, dimensionlessθhotκvon Kármán constant, dimensionlessµdynamic viscosity, kg/m · sdynamic viscosity at surface or wall temperature, kg/m · sµsνkinematic viscosity, m2/sBOOKCOMP, Inc.
— John Wiley & Sons / Page 520 / 2nd Proofs / Heat Transfer Handbook / Bejan[520], (82)Lines: 3613 to 3655———0.20847pt PgVar———Normal PagePgEnds: TEX[520], (82)NOMENCLATURE123456789101112131415161718192021222324252627282930313233343536373839404142434445ξρττbτoτTΦφ(x,y)φ(η)ψ(x,y)521dummy variable, dimensionlessfluid density, kg/m3shear stress, N/m2mean shear stress, N/m2free stream shear stress, N/m2turbulent shear stress, N/m2viscous dissipation, s−2stream function, dimensionlesssimilarity function, dimensionlessstream function, dimensionlessRoman Letter SubscriptsAblock designatordirect heat transfer componentAWadiabatic wallad, Badiabatic heat transfer coefficient on block Bair, bair temperature at block BavaverageBpertaining to Blasiusconjugate heat transfer componentblock designatorB/Aeffect on block B by dissipation from block Ab/(i,j )contribution of upstream blockbbottom of heat sinkcconduction thicknessrecovery factorcorecoreDdiameterffluidfrictionHhomogeneous art of solutionhheighthotmax(i,j )row and column indexLlengthlengthoptoptimumPparticular part of solutionfan powerPwpconstant pressureplateplaterefreferencessurfaceseheat sourcesubsubstrateBOOKCOMP, Inc.
— John Wiley & Sons / Page 521 / 2nd Proofs / Heat Transfer Handbook / Bejan[521], (83)Lines: 3655 to 3700———0.20847pt PgVar———Normal PagePgEnds: TEX[521], (83)522123456789101112131415161718192021222324252627282930313233343536373839404142434445FORCED CONVECTION: EXTERNAL FLOWSTwxyzthermalturbulentwidthx-coordinate directiony-coordinate directionz-coordinate directionGreek Letter Subscripts∞infinity∆ppressure lossδthickness of boundary layer, dimensionlessSuperscriptsmNq+∗Other∂∇exponentexponentexponentnormalized variablenormalized variablefirst derivativesecond derivativethird derivativepartial derivativevector operatorREFERENCESAnderson, A.
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— John Wiley & Sons / Page 522 / 2nd Proofs / Heat Transfer Handbook / Bejan[522], (84)Lines: 3700 to 3757———5.66856pt PgVar———Short PagePgEnds: TEX[522], (84)REFERENCES123456789101112131415161718192021222324252627282930313233343536373839404142434445523Davalath, J., and Bayazitoglu, Y. (1987). Forced Convection Cooling across RectangularBlocks, J.
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