air and the surface convection coefficient (T, h;) must be large enough to maintain a surface temperature T that is at least as high as the dew point (Ti >= Táp). Consider a windshield of length L = 800 mm and thickness t = 6 mm and driving conditions for which the vehicle moves at a velocity of V =50 mph in ambient air at T= 0°C. From laboratory experiments performed on a model of the vehicle, the average convection coefficient on the outer surface of the windshield is known to be correlated by an expression of the form NuL = 0.030REL^0.8 Pr^1/3, where Re, = VL/v. Air properties may be approximated as k =0.023 W/m-K, v = 12.5 x 106 m2/s, and Pr = 0.71. If Tap =10°C and T = 50°C, what is the smallest value of the inside convection coefficient required to prevent condensation on the inner surface?

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