Unformatted text preview: = i e p T T C m Q & & The logarithmic mean temperature difference and the surface area are C 63 . 11 10 30 24 30 ln 10 24 ln ln ° = ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ − − − = ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ − − − = Δ i s e s i e T T T T T T T 2 m 0.1885 = m) m)(5 012 . ( ππ = = DL A s The average heat transfer coefficient is determined from C . kW/m 12.1 2 ° = ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ ° = Δ = ⎯→ ⎯ Δ = W 1000 kW 1 ) C 63 . 11 )( m 1885 . ( W 468 , 26 2 ln ln T A Q h T hA Q s s & & The total rate of heat transfer is determined from kW 65 . 364 kJ/kg) 2431 )( kg/s 15 . ( = = = fg cond total h m Q & & Then the number of tubes becomes 13.8 = = = W 468 , 26 W 650 , 364 Q Q N total tube & & 84...
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 Fall '10
 Dr.DanielArenas
 Thermodynamics, Convection, Force, Mass, Heat, Heat Transfer, Log mean temperature difference, qtotal, 1 kW, 1.2 cm

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