A HEAT TRANSFER TEXTBOOK - THIRD EDITION Episode 2 Part 5 pptx

... parallel, black, opaque plates transfer heat by radiation, as shown in Fig. 1. 18. Find T 2 . 1. 15 Four infinite, parallel, black, opaque plates transfer heat by radiation, as shown in Fig. 1. 19. ... electrical resistance heater, releasing 10 00 W/m 2 . Calculate (a) the heater temperature, (b) the heat transfer from the methanol to the heater, and (c) the heat transfer f...

Ngày tải lên: 07/08/2014, 10:20

... with, we take U to be a constant value. This is fairly reasonable in compact single-phase heat exchangers. In larger exchangers, particu- larly in shell-and-tube configurations and large condensers, ... conguration. Figure 3 .5 shows the U-tubes of a two-tube-pass, one-shell-pass exchanger being installed in the 99 Figure 3 .5 Typical commercial one-shell-pass, two-tube-pass heat ex...

Ngày tải lên: 07/08/2014, 10:20

... [5.6] 13 . Isothermal ellipsoid of semimajor axis b and semiminor axes a conducts heat into an infinite medium at T ∞ ; b> ;a( see 4) 4πb  1 a 2  b 2 tanh 1   1 a 2  b 2  meter [5 .16 ] 24 6 26 2 ... 5 .1 0a Φ 1 ( Fo 1 = 0.565, Bi 1 = 0 . 21 05 ) = 0 .10 Φ 2 ( Fo 2 = 0.565, Bi 2 = 0 . 21 05 ) = 0 .10 and, with eqn. (5.7 3a) , Φ = Φ 1 +Φ 2 (...

Ngày tải lên: 07/08/2014, 10:20

...  = 3 20 φ− 3 28 0 φ 3    = 3 2u ∞ (6. 52) Since φ is a constant for any Pr [recall eqn. (6.46)], we separate variables: 2 t dδ t dx = dδ 2 t dx = 3 /u ∞  3 20 φ − 3 28 0 φ 3  §6.5 Heat transfer ... 0.0 021 35 so τ yx = (0.0 021 35 ) 1 2 ρu 2 ∞ = (0.0 021 35 )(1.05)(15) 2 2 = 0 .25 22 kg/m·s 2 and the force is τ yx A = 0 .25 22( 0.5) 2 =...

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... transitional value. Problems 335 6.31 A thin metal sheet separates air at 44 ◦ C, flowing at 48 m/s, from water at 4 ◦ C, flowing at 0.2m/s. Both fluids start at a leading edge and move in the same ... at 25 ◦ C flows at 0.7m/s over a 4 cm-long flat heater at 60 ◦ C. Find h, τ w , h(x = 0. 04 m), and δ(x = 0. 04 m). 6 .20 A large plate is at rest in water at 15 ◦ C. The plate i...

Ngày tải lên: 07/08/2014, 10:20

... and J. P. Hart- nett, editors, Advances in Heat Transfer, volume 6, pages 50 4 56 4. Academic Press, Inc., New York, 1970. [6.14] A. A. Žukauskas and A. B. Ambrazyavichyus. Heat transfer from a ... that of predicting laminar convection in a pipe. 7 .2 Heat transfer to and from laminar flows in pipes Not many industrial pipe flows are laminar, but laminar heating and cool- in...

Ngày tải lên: 07/08/2014, 10:20

... fins of a heat exchanger may form a rect- angular passage through which air flows. Sometimes, the passage cross- section is very irregular, as might happen when fluid passes through a clearance between ... situations, but all must be viewed critically. Many are based on limited data, and many incorporate systematic errors of one kind or another. In the face of a heat transfer situa...

Ngày tải lên: 07/08/2014, 10:20

... by Fujii and Imura [8. 16], Vliet [8. 17], Pera and Gebhart [8. 18] , and Al-Arabi and El-Riedy [8. 19], among others. 8. 5 Film condensation 431 on the same basis. The integration of eqn. (8. 47) subject ... 434 Natural convection in single-phase fluids and during film condensation 8. 5 Figure 8. 12 Results of the exact b.l. analysis of laminar film condensation on a vertical plate [8. 36]...

Ngày tải lên: 07/08/2014, 10:20

... on natural convection heat transfer from a horizontal plates. Int. J. Heat Mass Transfer, 17(1):135–1 42, 197 4. 458 Heat transfer in boiling and other phase-change congurations 9. 1 Figure 9. 1 ... Natural convection heat transfer from a plate with arbitrary inclination. Int. J. Heat Mass Transfer, 15(4): 755–767, 19 72. [8.17] G. C. Vliet. Natural convection local...

Ngày tải lên: 07/08/2014, 10:20

... quite ac- curate and widely-used, semi-empirical equation for correlating surface 470 Heat transfer in boiling and other phase-change congurations Đ9 .2 Table 9 .2 Selected values of the surface ... 25 8 2. 80 25 5 2. 29 25 3 1.95 Isopropyl alcohol 10 to 100 22 .90 0.0789 Mercury 5 to 20 0 490.60 .20 49 Methane 90 18.877 100 16. 328 115 12. 371 Methyl alcohol 10 to 60 24...

Ngày tải lên: 07/08/2014, 10:20

... Int. J. Heat Mass Transfer, 13: 1 425 –1 439 , 1970. [9. 23 ] J. S. Ded and J. H. Lienhard. The peak pool boiling heat flux from a sphere. AIChE J., 18 (2) :33 7 34 2, 19 72. [9 .24 ] A. L. Bromley. Heat transfer ... correlation for saturated two-phase flow boiling heat transfer inside horizontal and vertical tubes. J. Heat Transfer, 1 12( 1) :21 9 22 8, 1990. §10 .3 Radi...

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... 1.42ì10 5 air-ethanol 31 3 1. 45 air-helium 276 6.24 air-napthalene 30 3 0.86 air-water 31 3 2.88 argon-helium 2 95 8 .3 628 32 .1 1068 81.0 (dilute solute, 1 )-( liquid solvent, 2) T (K) D 12 (m 2 /s) ethanol-benzene ... D 12 (m 2 /s) ethanol-benzene 288 2. 25 10 9 benzene-ethanol 298 1.81 water-ethanol 298 1.24 carbon dioxide-water 298 2.00 ethanol-water 288 1.00 methane-water 2...

Ngày tải lên: 07/08/2014, 10:20