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Heat Transfer Handbook part 89. The Heat Transfer Handbook provides succinct hard data, formulas, and specifications for the critical aspects of heat transfer, offering a reliable, hands-on resource for solving day-to-day issues across a variety of applications. | TRANSVERSE HIGH-FIN EXCHANGERS 875 Sbda Sf SfPf 2NL 1 2 e S with the diagonal pitch given by eq. 11.165 . In eq. 11.173 the range of parameters is 1000 Re 10 000 10.67 mm db 26.01 mm da - db 5.20 mm b ---------- 9.70 mm 2 0.25 mm Sf 0.70 mm 24.78 mm Pt 49.55 mm 16.20 mm de 34.00 mm Pt db 0.48 mm --------- 1.64 db 4.34 Pt - db 1 25.2 Pf Sf 2.28 mm Pf 5.92 mm 0.45 Pt db Pd dr 2.50 20.32 mm Pi 52.40 mm Ganguli et al. 1985 proposed the following correlation for three or more rows of finned tubes Nu 0.38Re0 6 Pr1 3 k C x0.15 Sb S J 11.174 where dbG Re R The correlation of eq. 11.174 is vaiid for 1800 Re 100 000 2.30 mm Pf 3.629 mm 11.176mm db 19.05mm 27.432mm Pt 98.552mm 5.842 mm b da - db 19.05 mm 1 S 50 2 Sb 0.254 mm Sf 0.559 mm Other correlations include those of Baauer 11964 S iel ijli i leirrg 11965 Kuntysh and lokhvedor 1971 and Mirkovic 1974 . More recent correlations include those of Zhukauskas 1974 Weierman 1976 Hofmann 1976 Ehlmady and Biggs 1979 Biery 1981 Gianolio and Cuti 1981 Brandt and Wehle 1983 and Nir 1991 . Many of hem are cited tty Kroger 1998 . 11.7.5 Pressure Loss Correlations for Staggered Tubes Some of the earl ier correlations for the static pressure drop through bundtes oc circl.il ar finned tubes are those of Jameoon 11945 Gunter and Shaw 11945 and Ward and 876 HEAT EXCHANGERS Young 1959 . A frequently used correlation is that of Robinson and Briggs 1966 for staggered tubes AP 18.03 G .Re-W - 7 H p db Pd 11.175 for nr rows and where dbG Re R and where Pd is given by eq. 11.165 . Equation 11.175 is valid for 2000 Re 50 000 2.31 mm Pf 2.82 mm 18.64 mm db 40.89 mm 42.85 mm Pt 114.3 mm 39.68 mm da 69.85 mm 37.11mm Pi 98.89 mm 10.52mm b da db 14.48mm 1.8 4.6 2 db Vampola 1966 proposed the correlation AP 0.7315Gnr Re 0245 P d P db Pt db 0-70 de_y Pf db 11.176 where the Reynolds number equivalent diameter and limits of ajopCcahi 11 t.y are identical to those following eq. 11.173 . 11.7.6 Overall Heat Transfer Coefficient Because the air- and .
