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6.25 Experimental measurements of the convection heat transfer coefficient for a square bar in cross flow yielded the following values: 50 W/m2 K when =40 W/m2-K when 20 m/s ½=15 m/s 0.5 m Air Assume that the functional form of the Nusselt number is Nu C Re Pr, where C, m, and n are constants. (a) What will be the convection heat transfer coefficient for a similar bar with L-1 m when V 15 rh/s? (b) What will be the convection heat transfer coefficient for a similar bar with L = 1 m when V= 30 m/s? (c) Would your results be the same if the side of the bar, rather than its diagonal, were used as the char- acteristic length?

if l is increased and everything remains the same what will happen to h?

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