Consider a sphere of diameter 5 cm, a cube of side length 5 cm, and a rectangular prism of dimension
Now all three of these geometries are exposed to ambient air at 33°C on all of their surfaces with a heat transfer coefficient of 12 W/m2 K. Determine how long it will take for the temperature of each geometry to rise to 25°C.
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Heat and Mass Transfer: Fundamentals and Applications
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- Q2/ A 3-m internal diameter spherical tank made of 2-cm-thick stataless steel (k= 15 W/m 0°C. The tank is located in a room whose %3D C) is used to store iced water at Te temperature is T-22°C. The walls of the room are also at 22°C. The outer surface of the tank is black and heat transfer between the outer surface of the tank and the surroundings is by natural convection and radiation. The convection heat transfer coefficients at the inner and the outer surfaces of the tank are h-80 W/m2 C and h 10 W/m2 C, respectively. Determine (a) the rate of heat transfer to the iced water in the tank and (b) the amount of ice at 0°C that melts during a 24-h period.arrow_forwardHello, Kindly help me with this question. Thank youarrow_forwardConsider steady heat transfer between two large parallel plates at constant temperatures of T1=300 K and T2=200 K that are L= 2cm apart. Assuming surfaces to be black (emissivity = 1), determine the rate of heat transfer between the plates per unit surface area assuming the gaps in between the plates are filled with atmospheric air (k=0.0219 W/m.C).arrow_forward
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