Question

2 ICED WATER IN A SPHERICAL CONTAINER (10 POINTS) Troom = 30°C Iced water O , D; = 5 m 1.5 cm T = 0°C A 5-m-internal-diameter spherical tank made of 1.5-cm-thick stainless steel (k = 15 W/( m K )) is used to store iced water at 0°C. The tank is located in a room whose temperature is 30°C. The walls of the room are also at 30°C. Heat transfer between the outer surface of the tank and the room air 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 80 W/(m².K) and 10 W/(m2.K), respectively. The radiation heat transfer coefficient is estimated to be 5 W/(m2K). The latent heat of fusion of water at atmospheric pressure is hif = 333.7 kJ/kg. Consider steady- state conditions. a) Determine the amount of ice that melts during a 24-h period.

Answer 1

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Roq = (Rcond) tronuli +lReq) = 1.59) x) -Ч + 1.2пчхо-, в.33 ( x) 0 -9 - 1.o192 х 10-2. = 1. o | o2 x To Sv q = To - T4 30 – о Ес 1-о) oz xo-2 = 29, 69 52 W от 29.6 95 LKW . o 24 h = 29.5 2 xчx6ox 46 29. с 9,2 х 24 x 60 x Go m xhi - m = 29 . С 95 x2 Хоох бо 13 ч = Inc. 1. (3 * І.