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A counterflow, twin-tube heat exchanger is made bybrazing two circular nickel tubes, each 40 m long,together as shown below. Hot water flows through thesmaller tube of 10-mm diameter and air at atmospheric pressure flows through the larger tube of 30-mm diameter. Both tubes have a wall thickness of 2 mm. The thermal contact conductance per unitlength of the brazed joint is
Employ the
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Fundamentals of Heat and Mass Transfer
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- Please explain with steps.arrow_forwardA heat exchanger is to be designed to condense 8 kg/sec of an organic liquid (tsat=80°C, hfg=600 KJ/kg) with cooling water available at 15°C and at a flow rate of 60 kg/sec. The overall heat transfer coefficient is 480 W/m2 -°C calculate: a) The number of tubes required. The tubes are to be of 25 mm outer diameter, 2 mm thickness and 4.85 m length b) The number of tube passes. The velocity of the cooling water is not to exceed 2 m/sec.arrow_forwardYou as a Biochemical Engineer in an ezyme industries is assigned to handle a counter flow double pipe heat exchanger with A,= 9 m2 which used for cooling a fermentation broth (c, = 3.15 kJ/kg. K) at a rate of 10 kg/s with an inlet temperature of 90°C. The water used as coolant enters the heat exchanger at a rate of 8 kg/s with an inlet temperature of 10°C. The plant data gave the following equation for the overall heat transfer coefficient (in W/m².K): 600 %3D 1 2 • U.8 |m. where m. and m, are the cold and hot stream flow rates in kg/s, respectively.arrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning