Air at 30 degree Celsius temperature flows at 45 m/s past a wet flat p...
Explanation: h m = 0.0296 (Re) -0.2 (V)/ (Sc) 0.667.
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Air at 30 degree Celsius temperature flows at 45 m/s past a wet flat p...
To estimate the value of the mass transfer coefficient, we can use the Sherwood number correlation for forced convection over a flat plate. The Sherwood number (Sh) is defined as the dimensionless mass transfer coefficient, and it can be related to the Reynolds number (Re) and Schmidt number (Sc) as follows:
Sh = 0.023 * Re^0.8 * Sc^0.33
To calculate the Reynolds number, we need to determine the velocity and characteristic length. The velocity is given as 45 m/s, and the characteristic length is the length of the flat plate, which is 0.5 m. Therefore:
Re = (velocity * length) / kinematic viscosity
= (45 * 0.5) / (0.256 * 10^-4)
= 87,890
Next, we need to determine the Schmidt number, which is the ratio of momentum diffusivity to mass diffusivity:
Sc = kinematic viscosity / mass diffusivity
= (0.256 * 10^-4) / ? (unknown value)
Unfortunately, the water vapor diffusivity in air is not provided, so we cannot calculate the Schmidt number or the mass transfer coefficient without this information.