Free Convection Flow up a Vertical Wall

Nu/ = —

 (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

 Conditions

Correlation

 0.0668 j Re,,Pr
 Laminar, fully developed, Tm, q= cst, Pr > 0.6′, Re,, < 2300 "" Laminar, fully developed, Tm, 7"s = cst, Pr > 0.6, Rcj < 2300 Laminar, thermal entry length T„, Ts ~ cst, Pr » 1 or unheated starting length

 Nu. j 4.36 Nuj — 3.66

 Nuj — 3.66-

О + 0.04

 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.

 Nu., = 0.023 Re4,5 Pr17 ’ Nu,; = 0.027 Re4,7′ Pr Nuj = 4.82 + 0.0185( Re,, Pr) Nu, y = 5 + 0.025(Re,; Pr)

 TABLE 4.10 Constants for External Flow Correlation

Note: Tm is the mean bulk temperature and Tm = 0.5 (Tm ln + T„, ,mt).

 Red C M C M 0.4-4 0.989 0.33 1-400 0.75 0.4 4-400 0.911 0.385 400-1000 0.51 0.5 40-4000 0.683 0.466 103 — 2 x 10′ 0.26 0.6 4000-40 000 0.193 0.618 2 x105-106 0.076 0.7 40 000-400 000 0.027 0.805
 TABLE 4.11 Constants for External Flow Correlation

Flow Past a Horizontal Pipe

 I/6
 Nuj =
 0.492 Pr
 0.387(Gr Pr)
 / / 1 + V
 0.825 +
 (4.200)

 0.14
 JTf Vw
 0.037(Re°’75 — 180)Pr°’42
 Nu,
 /1.14^-14 0.54
 = 0.037((1.32 x 104) — 180) x 7.980 42
 = 103.3