6.64 Consider application of the naphthalene sublimation technique (Problem 6.63) to a gas turbine blade that is coated with naphthalene and has a surface area ofA, = 0.05 m². To

determine the average convection heat transfer coef-ficient for a representative operating condition, anexperiment is performed in which the coated blade isexposed for 30 min to atmospheric air at the desiredvelocity and a temperature of T. = 27°C. During theexperiment the surface temperature is T,its conclusion the mass of the blade is reduced byAm = 8 g. What is the average convection heat transfercoefficient associated with the operating condition?27°C, and at%3D%3D