The interior of a refrigerator whose dimensions are 0.05 x 0.05 dam base area and 1.25 m high, must be kept at 4 °C. The refrigerator walls are constructed of two steel sheets (k= 35 kcal/h.m.°C) 3 mm thick, with 65 mm of material insulation (k=0.213 kcal/h.m.°C) between them. The film coefficient of the inner surface is 10 kcal/h.m².°C, while on the external surface it varies from 8 to 12.5 kcal/h.m².°C. Calculate: a) The power (in HP) of the refrigerator motor so that the heat flux removed from the inside the refrigerator maintain the specified temperature, in a kitchen whose temperature can vary from 21 to 36 °C; b) The temperatures of the inner and outer surfaces of the wall. Given 1 HP = 641.2 Kcal/h
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- Answer this ASAP The diameter of the tube is 25 mm. The specific heat of water is 4.18 kJ/kg.°C. The overall heat transfer coefficient is 0.7 kW/m².°C. 1. Schematic of temperature distribution 2.ΔTLMTD 3.Actual heat transfer rate 4.Cmin 5.Maximum heat transfer ratearrow_forward215arrow_forwardThe temperature of a gas stream is measured by a thermocouple whose junction can be approximated as a 1-mm-diameter sphere. Take the junction’s properties as: k of 32 W/m K, density of 8.2 kg/m^3, c of 300 J/Kg K. On its surface, the overall heat transfer coefficient is 200 W/m^2 K. Neglect any conduction loss from the sphere to other parts of the thermocouple. Create a plot of measurement error as a function of time for the thermocouple, expressed as a fraction of the initial temperature difference.arrow_forward
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