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Air enters a rectangular duct measuring 30 cm by 40 cm with a velocity of 8.5 m/s and a temperature of 40 degree Celsius. The flowing air has a thermal conductivity 0.028 W/m K, kinematic viscosity 16.95 * 10 -6 m2/s and from empirical correlations the Nusselt number has been approximated to be 425. Find out the flow Reynolds number

Air enters a rectangular duct measuring 30 cm by 40 cm with a velocity of 8.5 m/s and a temperature of 40 degree Celsius. The flowing air has a thermal conductivity 0.028 W/m K, kinematic viscosity 16.95 * 10 -6 m2/s and from empirical correlations the Nusselt number has been approximated to be 425. Find out the flow Reynolds number Correct Answer 0.1719 * 10 6

R e = V d e/v.

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