A Counter-flow heat exchanger (water-to-water) with these specifications. Hot water enters at 95 °C while cold water enters at 20 °C. The exit temperature of hot water is 15 °C greater than that of cold water, and the mass flow rate of hot water is 50 percent greater than that of cold water. The product of heat transfer surface area and the overall heat transfer coefficient is 1400 W/K. Taking the specific heat of both cold and hot water to be C, = 4180 J/kg.K. Calculate: (a) The outlet temperature of the cold water, (b) LMTD (c) The effectiveness of the heat exchanger,

A Counter-flow heat exchanger (water-to-water) with these specifications. Hot water enters at 95 °C while cold water enters at 20 °C. The exit temperature of hot water is 15 °C greater than that of cold water, and the mass flow rate of hot water is 50 percent greater than that of cold water. The product of heat transfer surface area and the overall heat transfer coefficient is 1400 W/K. Taking the specific heat of both cold and hot water to be C, = 4180 J/kg.K. Calculate: (a) The outlet temperature of the cold water, (b) LMTD (c) The effectiveness of the heat exchanger,

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.46P

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Geothermal heat pumps, or water-source heat pumps, are classified as either _____loop or _____loop systems.
Water (Cp = 4180 J/kg · °C) enters the 2.5-cm internal-diameter tube of a double-pipe counter-flow heat exchanger at 17°C at a rate of 3 kg/s. Water is heated by steam condensing at 120°C (hfg = 2203 kJ/kg) in the shell. If the overall heat transfer coefficient of the heat exchanger is 900 W/m2 · °C, determine the length of the tube required in order to heat the water to 80°C using (a) the LMTD method and (b) the Effectiveness-NTU method
A Counter-flow heat exchanger (water-to-water) with these specifications. Hot water enters at 95 oC while cold water enters at 20 oC. The exit temperature of hot water is 15 oC greater than that of cold water, and the mass flow rate of hot water is 50 percent greater than that of cold water. The product of heat transfer surface area and the overall heat transfer coefficient is 1400 W/K. Taking the specific heat of both cold and hot water to be Cp = 4180 J/kg.K, Calculate: (a) The outlet temperature of the cold water, (b) LMTD (c) The effectiveness of the heat exchanger, (d) The mass flow rate of the cold water, (e) The heat transfer rate.
A thin-walled double-pipe counter-flow heat exchanger is to be used to cool oil (Cpo= 2200 J/kg.K) from 150°C to 40°C at a rate of 2 kg/s by water (Cpw= 4180 J/kg.K) that enters at 22°C at a rate of 1.5Kg/s. If the diameter of the tube is 2.5 cm, and its length is 6 m, determine * The rate of heat transfer in the heat exchanger * The outlet temperature of the cold fluid * The Log Mean Temperature Difference (LMTD) * The overall heat transfer coefficient
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Hot oil is to be cooled in a double-tube counter-flow heat exchanger. The copper inner tubes have a diameter of 2 cm and negligible thickness. The inner diameter of the outer tube (the shell) is 3 cm. Water flows through the tube at a rate of 0.5 kg/s, and the oil through the shell at a rate of 0.8 kg/s. Taking the average temperatures of the water and the oil to be 45°C and 80°C, respectively, determine the overall heat transfer coefficient of this heat exchanger.
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