Refrigeration Truck White Paper

The roof of a refrigerated truck compartment is of composite construction, consisting of a layer of foamed urethane insulation (t2 = 50 mm, ki = 0.026 W/m ∙ K sandwiched between aluminum alloy panels (11 = 5 mm, kp = 180 W/m ∙ K). The length and width of the roof are L = 10 m and W = 3.5 m, respectively, and the temperature of the inner surface is Ts,i = – 10°C. Consider conditions for which the truck is moving at a speed of V= 105 km/h, the air temperature is T = 32°C, and the solar irradiation is Gs = 750 W/m2. Turbulent flow mil) be assumed over the entire length of the roof.
Refrigerator Truck White Papers
(a) For equivalent values of the solar absorptivity and the emissivity of the outer surface (as = 8 = 0.5), estimate the average temperature Ts,o of the outer surface. What is the corresponding heat load imposed on the refrigeration system? (b) A special finish (as = 0.15, ε = 0.8) may be applied to the outer surface. What effect would such an application have on the surface temperature and the heat load? Refrigerator Truck White Papers (c) If, with as = ε = 0.5, the roof is not insulated (12 = 0), what are the corresponding values of the surface temperature and the heat load? SOLUTION: Refrigerator Truck White Papers