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In: Mechanical Engineering

1. Engine oil (cp = 2100 J/kg-°C) is to be heated from 20 °C to 60...

1. Engine oil (cp = 2100 J/kg-°C) is to be heated from 20 °C to 60 °C at a rate of 0.3 kg/s in a 2-cmdiameter thin-walled copper tube by condensing steam outside at a temperature of 130 °C (hfg = 2174 kJ/kg).

a. For an overall heat transfer coefficient of 650 W/m2 -°C, determine the rate of heat transfer and the length of tube required to achieve it. Determine also the rate of steam condensation, in kgsteam/sec. (Ans: 25.2 kW; 7.0 m)

b. What would the tube length have to be if we wanted to heat the oil to 100 °C in the same 2-cm diameter tube and at the same flow rate? How about heating to 120 °C?

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Expert Solution

samet mamat answered 2 years ago
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