Liquid mercury at a temperature of 315?C flows at a velocity of 10 cm/s over a staggered bank of 5/8-in. 16 BWG stainless steel tubes, arranged in an equilateral triangular array with a pitch-to-diameter ratio of 1.375. If water at 2 atm pressure is being evaporated inside the tubes, estimate the average rate of heat transfer to the water per meter length of the bank, if the bank is 10 rows deep and has 60 tubes in it. The boiling heat transfer coefficient is 20,000 W/(m2 K).GIVENLiquid mercury flow over an equilaterally staggered tube bankInlet mercury temperature (Tm,in) = 315?CMercury velocity (Us) = 10 cm/s = 0.1 m/sTubes are 5/8 in., 26 BWG stainless steelPitch to diameter ratio (S/D) = 1.375Water at 2 atm pressure is being evaporated within the tubesNumber of rows of tubes (N) = 10Number of tubes (Nt) = 60The boiling heat transfer coefficient (hb) = 20,000 W/(m2 K)ASSUMPTIONSSteady stateTubes are type 304 stainless steelTemperature change of the mercury across the tube bank isnegligible

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Mercury Tmn = 315°C U.-0.1 m/s