How much fiberglass insulation [k = 0.035 W/(m K)] is needed to guarantee that the outside temperature of a kitchen oven will not exceed 43?C? The maximum oven temperature to be maintained by the convectional type of thermostatic control is 290?C, the kitchen temperature may vary from 15?C to 33?C and the average heat transfer coefficient between the oven surface and the kitchen is 12 W/(m2 K).GIVENKitchen oven wall insulated with fiberglassFiberglass thermal conductivity (k) = 0.035 W/(m K)Convective transfer coefficient on the outside of wall ( hc ) = 12 W/(m2 K)Maximum oven temperature (Ti) = 290?CKitchen temperature (T??) may vary: 15?C ASSUMPTIONSOne dimensional, steady state heat transfer prevailsThe temperature of the inside of the wall (Twi) is the same as the oven temperatureThe thermal resistance of the metal wall of the oven isnegligible

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TWOS-43°C TwS 290°C- 9k 15°CS T.S33°C