A stream of air at 100 kPa pressure and 300 K is flowing on the top...

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A stream of air at 100 kPa pressure and 300 K is flowing on the top surface of a thin flat sheet of solid naphthalene of length 0.2 m with a velocity of 20 m/sec. The other data are: Mass diffusivity of naphthalene vapor in air = 6*10-6 m2/sec Kinematic viscosity of air = 1.5 * 10-5 m2.sc Concentration of naphthalene at the air-solid naphthalene interface 1* 10-5 kmol/m³ Calculate: the average mass transfer coefficient over the flat plate the rate of loss of naphthalene from the surface per unit width Note: For heat transfer over a flat plate, convective heat transfer coefficient for laminar flow can be calculated by the equation Nu = 0.664Re 1/2 Pr1/3 You may use analogy between mass and heat transfer. A stream of air at 100 kPa pressure and 300 K is flowing on the top surface of a thin flat sheet of solid naphthalene of length 0.2 m with a velocity of 20 m/sec. The other data are: Mass diffusivity of naphthalene vapor in air = 6*10-6 m2/sec Kinematic viscosity of air = 1.5 * 10-5 m2.sc Concentration of naphthalene at the air-solid naphthalene interface 1* 10-5 kmol/m³ Calculate: the average mass transfer coefficient over the flat plate the rate of loss of naphthalene from the surface per unit width Note: For heat transfer over a flat plate, convective heat transfer coefficient for laminar flow can be calculated by the equation Nu = 0.664Re 1/2 Pr1/3 You may use analogy between mass and heat transfer.