Unformatted text preview: 10 702 . 1 m) (0.22 m/s ) 60 / 250 ( Re × = × = υ = − ∞ L V L which is smaller than the critical Reynolds number. Thus we have laminar flow. Using the proper relation for Nusselt number, heat transfer coefficient is determined to be C . W/m 75 . 16 ) 5 . 138 ( m 22 . C W/m. 02662 . 5 . 138 ) 7255 . ( ) 10 386 . 5 ( 664 . Pr Re 664 . 2 3 / 1 5 . 4 3 / 1 5 . ° = ° = = = × = = = Nu L k h k hL Nu L The temperature of aluminum plate then becomes C 50.0 ° = ° × + ° = + = ⎯→ ⎯ − = ∞ ∞ ] ) m 22 . ( 2 )[ C . W/m 75 . 16 ( W ) 12 4 ( C 20 ) ( 2 2 s s s s hA Q T T T T hA Q & & Discussion In reality, the heat transfer coefficient will be higher since the transistors will cause turbulence in the air. 780...
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 Fall '10
 Dr.DanielArenas
 Fluid Dynamics, Thermodynamics, Convection, Force, Mass, Heat, Heat Transfer, critical Reynolds number

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