Question

Cold water enters a counter flow heat exchanger at 20ºC at a rate of 10 kg/s, where it is heated by a hot water stream that enters the heat exchanger at 80ºC at a rate of 2 kg/s. Assuming the specific heat of water to remain constant at Cp=4.18 kJ/(kg.ºC), determine the maximum heat transfer rate and the outlet temperatures of the cold and the hot water streams.

Answer #1

A thin-walled cross-flow heat exchanger is used to heat a
petrochemical whose specific heat is 1800 J (kg K)-1
with hot water (Cp = 4180 J (kg K)-1). The
petrochemical enters the heat exchanger at 20oC at a
rate of 3.7 kg s-1, whilst the water stream enters at
110oC at a rate of 2.5 kg s-1. The heat
transfer surface area of the heat exchanger is 4.8 m2
and the overall heat transfer coefficient is 940.30 W
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Hot water enters a counter-flow double-pipe heat exchanger at
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Oil enters a counterflow heat exchanger at 600 K with a mass
flow rate of 10 kg/s and exits at 350 K. A separate stream of
liquid water enters at 20°C, 5 bar. Each stream experiences no
significant change in pressure. Stray heat transfer with the
surroundings of the heat exchanger and kinetic and potential energy
effects can be ignored. The specific heat of the oil is constant,
c = 2 kJ/kg · K.
If the designer wants to ensure...

Oil enters a counterflow heat exchanger at 525 K with a mass
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liquid water enters at 20°C, 5 bar. Each stream experiences no
significant change in pressure. Stray heat transfer with the
surroundings of the heat exchanger and kinetic and potential energy
effects can be ignored. The specific heat of the oil is constant, c
= 2 kJ/kg · K. If the designer wants to ensure...

Oil enters a counterflow heat exchanger at 525 K with a mass
flow rate of 10 kg/s and exits at 275 K. A separate stream of
liquid water enters at 20°C, 5 bar. Each stream experiences no
significant change in pressure. Stray heat transfer with the
surroundings of the heat exchanger and kinetic and potential energy
effects can be ignored. The specific heat of the oil is constant, c
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Milk enters a heat exchanger at 200C and is heated to
750C using hot water at a temperature of
900C. 1) If exit temperature of water is
800C, assume parallel flow and determine the log mean
temperature difference between water and milk.
2) assume countercurrent flow and determine the log mean
temperature difference between water and milk.
3)assume countercurrent flow and determine the overall heat
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Assume specific heat of water as...

Jack is operating a tubular, water-water heat exchanger when
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Stays the same
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A thin-walled double pipe counter flow heat exchanger is to be
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Saturated water vapor leaves a steam turbine at a flow rate of
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2000 W/m2K, determine the required heat exchanger
surface area and the water flow rate. cp,c...

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