Free Convection Flow up a Vertical Wall
Nu/ = —
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(4.198) |
Tst = 0.5(T — + Tp) Flow Upward on a Horizontal Plane
Nu, = 0.70(Gr Pr)1/4 Gr Pr < 4 x 10′
Nu, = 0.155(Gr Pr)1/3 Gr Pr > 4 x 107
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Conditions |
Correlation
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©■ |
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0.0668 j Re,,Pr |
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О + 0.04
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Turbulent, fully developed, Tm, 160 > Pr > 0.6, Re, > 2300, t > 10 A Turbulent, fully developed, Tn}, 16 700 > Pr > 0.7, Rerf > 104, > 10 Liquid metals, turbulent, fully developed, Tnt, q" = cst, 3.6 xlO3 < Rerf < 9.0.5 x10s, 102 < Pe,? < 104 Liquid metals, turbulent, fully developed. |
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TABLE 4.10 Constants for External Flow Correlation |
Note: Tm is the mean bulk temperature and Tm = 0.5 (Tm ln + T„, ,mt).
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Red |
C |
M |
C |
M |
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0.4-4 |
0.989 |
0.33 |
1-400 |
0.75 |
0.4 |
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4-400 |
0.911 |
0.385 |
400-1000 |
0.51 |
0.5 |
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40-4000 |
0.683 |
0.466 |
103 — 2 x 10′ |
0.26 |
0.6 |
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4000-40 000 |
0.193 |
0.618 |
2 x105-106 |
0.076 |
0.7 |
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40 000-400 000 |
0.027 |
0.805 |
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TABLE 4.11 Constants for External Flow Correlation |
Flow Past a Horizontal Pipe
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I/6 |
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Nuj = |
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0.492 Pr |
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0.387(Gr Pr) |
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/ / 1 + V |
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0.825 + |
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0.14 |
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JTf Vw |
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0.037(Re°’75 — 180)Pr°’42 |
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Nu, |
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/1.14^-14 0.54 |
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= 0.037((1.32 x 104) — 180) x 7.980 42 |
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= 103.3 |
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Posted in INDUSTRIAL VENTILATION DESIGN GUIDEBOOK |