A flat plate coated with a volatile substance (species A) is exposed to dry, atmospheric air in parallel flow with T_∞ = 20°C and u_∞ = 8 m/s. The plate is maintained at a constant temperature of 134°C by an electrical healing element, and the substance evaporates from the surface. The plate has a width of 0.25 m (normal to the plane of the sketch) and is well insulated on the bottom.

The molecular weight and the latent heat of vaporization of species A are M_A = 150 kg/kmol and h_k = 5.44 x 10⁶ J/kg, respectively, and the mass diffusivity is D_AB = 7.75 x 10^-7 m²/s. If the saturated vapor pressure of the substance is 0.12 atm at 134°C, what is the electrical power required maintaining steady-state conditions?

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Air ParT, Coating Heater L= 4 m