Water is to be heater from 10 to 30?C, at the rate of 300 kg/s by atmospheric pressure steam in a single-pass shell-and-tube heat exchanger consisting of 1-in schedule 40 steel pipe. The surface coefficient on the steam side is estimated to be 11,350 W/(m2 K). A pump is available which can deliver the desired quantity of water provided the pressure drop through the pipes does not exceed 15 psi. Calculate the number of tubes in parallel and the length of each tube necessary to operate the heat exchanger with the available pump.GIVENSingle-pass shell-and-tube heat exchangerWater is heated by atmosphere steamWater temperaturesTw,in = 10?CTw,out = 30?CWater flow rate (mw) = 300 kg/sInner tube: 1 in schedule 40 steel pipeMaximum water pressure drop (??p) = 15 psi = 103,422 N/m2Steam side heat transfer coefficient (ho ) = 11,350 W/(m2 K)ASSUMPTIONSThe tube is smoothThe tube is 1% carbon steelUniform pipe surface temperatureFully developed flow in pipeWater flow is turbulent to insure good heattransfer

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1 In Schedule 40 Sleam Water Twout - 30°C Twn = 10°C mw= 300 kg/s