Cooled air is flowing through a long sheet metal air conditioning duct, 0.2 m high and 0.3 m wide. If the duct temperature is 10?C and passes through a crawl space under a house at 30?C, estimate(a) The heat transfer rate to the cooled air per meter length of duct.(b) The additional air conditioning load if the duct is 20 m long.(c) Discuss qualitatively the energy conservation if the duct were insulated with glass wool.GIVENAn air conditioning duct in a crawl spaceDuct height (H) = 0.2 mDuct width (w) = 0.3 mDuct temperature (Ts) = 10?CAmbient temperature (T??) = 30?CASSUMPTIONSAmbient air is stillDuct temperature is constant and uniformRadiation is negligibleEdge effects are negligibleNo condensation on the ductsurface

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Alr T- 30°C w-0.3 m T.= 10 °C H=0.2 m Uninsulated Insulated