A refrigeration truck is traveling at 80 mph on a desert highway where the air temperature is 50?C. The body of the truck may be idealized as a rectangular box, 3 m wide, 2.1 m high, and 6 m long, at a surface temperature of 10?C. Assume that the heat transfer from the front and back of the truck may be neglected, that the stream does not separate from the surface, and that the boundary layer is turbulent over the whole surface. If, for every 3600 W of heat loss, one ton capacity of the refrigerating unit is necessary, calculate the required tonnage of the refrigeration unit.GIVENA refrigeration truck traveling on a desert highwaySpeed of truck (U??) = 80 mphAir temperature (T??) = 50?CTruck may be idealized as a box: 3 m wide, 2.1 m high, 6 m longTruck surface temperature (Ts) = 10?COne ton of refrigeration unit is needed for every 3600 W of heat lossASSUMPTIONSThe heat transfer from the front and back of the truck is negligibleAir stream does not separate from the surfaceThe boundary layer is turbulent over the whole surfaceMoisture of the air is negligibleRadiative heat transfer isnegligible

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2,1 m Alr U-80 mph T.= 50°C T-10°C 3 m