We will use some of the data from Example 4.18 to show the use of the eff ectiveness-NTU method in solving problems when both exit temperatures are unknown. A liquid food (specifi c heat 4.0 kJ/[kg °C]) fl ows in the inner pipe of a double-pipe heat exchanger. The liquid food enters the heat exchanger at 20°C. The fl ow rate of the liquid food is 0.5 kg/s. In the annular section, hot water at 90°C enters the heat exchanger and fl ows in countercurrent direction at a fl ow rate of 1 kg/s. The average specifi c heat of water is 4.18 kJ/(kg °C). The average overall heat transfer coeffi cient based on the inside area is 2000 W/(m 2 °C), and the diameter of the inner pipe is 5 cm and length is 6.45 m. Assume steady state conditions. Calculate the exit temperature of liquid food and water.

Question-Answer › Category: Food Engineering › We will use some of the data from Example 4.18 to show the use of the eff ectiveness-NTU method in solving problems when both exit temperatures are unknown. A liquid food (specifi c heat 4.0 kJ/[kg °C]) fl ows in the inner pipe of a double-pipe heat exchanger. The liquid food enters the heat exchanger at 20°C. The fl ow rate of the liquid food is 0.5 kg/s. In the annular section, hot water at 90°C enters the heat exchanger and fl ows in countercurrent direction at a fl ow rate of 1 kg/s. The average specifi c heat of water is 4.18 kJ/(kg °C). The average overall heat transfer coeffi cient based on the inside area is 2000 W/(m 2 °C), and the diameter of the inner pipe is 5 cm and length is 6.45 m. Assume steady state conditions. Calculate the exit temperature of liquid food and water.

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Sumit asked 1 year ago

We will use some of the data from Example 4.18 to show the use of the
eff ectiveness-NTU method in solving problems when both exit temperatures are unknown. A liquid food (specifi c heat 4.0 kJ/[kg °C]) fl ows in the
inner pipe of a double-pipe heat exchanger. The liquid food enters the heat
exchanger at 20°C. The fl ow rate of the liquid food is 0.5 kg/s. In the annular
section, hot water at 90°C enters the heat exchanger and fl ows in countercurrent direction at a fl ow rate of 1 kg/s. The average specifi c heat of water
is 4.18 kJ/(kg °C). The average overall heat transfer coeffi cient based on the
inside area is 2000 W/(m 2
°C), and the diameter of the inner pipe is 5 cm and
length is 6.45 m. Assume steady state conditions. Calculate the exit temperature of liquid food and water.

Question Tags: Food tech.