In a parallel flow heat exchanger, hot fluid enters the heat exchanger at a temperature of 150°C and a mass flow rate of 3 kg/s. The cooling medium enters the heat exchanger at a temperature of 30°C with a mass flow rate of 0.5 kg/s and Examiner's Signature Moderator's Signature Page |5 leaves at a temperature of 70°C. The specific heat capacities of the hot and cold fluids are 1150 J/kg-K and 4180 J/kg-K, respectively. The convection heat transfer coefficient on the inner and outer side of the tube is 300 W/m?.K and 800 W/m?.K, respectively. For a fouling factor of 0.0003 m².K/W on the tube side and 0.0001 m?.K/W on the shell side, determine the overall heat transfer coefficient, the exit temperature of the hot fluid as well as the surface area of the heat exchanger.

A heat exchanger is being investigated as a waste heat recovery device. A heat exchanger is common device for using a hot fluid to heat a cold fluid without the fluids mixing.  The following information is known.  The cold fluid stream of liquid A enters at 294.2 K and leaves the device at a temperature of 320.91 K.  Liquid A flows at a rate of 0.006 Kg/s and has a specific heat of 4180 J/(Kg K).  Liquid B enters the device at a temperature of 350.2 K.  Liquid B flows at a rate of 0.005 Kg/s and has a specific heat of 3900 J/(Kg K  The dead state is at 293.2 K and 1 bar.  The device is adiabatic and the pressure losses are neglected in this problem.  Both liquids are incompressible materials. Tout=316.154K Answer the following:  If the exiting liquid B is not used for any useful purpose, calculate the exergy destroyed associated with it.

based on a double-pipe counter flow heat exchanger to be used to cool oil that enters the heat exchanger at 300°F to 105°F at a rate of 5 lbm/s by water that enters at 70°F at a rate of 3 Ibm/s. The diameter of the tube is 1 in. and the length is 20 ft. The measured overall heat transfer coefficient of this heat exchanger is 2.14 Btu/s-ft2-°F. [Oil, c, = 0.525 Btu/lbm°F, Water, c, = 1.0 %3D Btu/lbm°F] The logarithmic mean temperature difference in °C is 46.1 cannot be determined 35.0 59.4

A shell-and-tube heat exchanger is used to cool compressed liquid methanol from 176 °F to 104 °F. The methanol flows on the shell side of the exchanger. The coolant is water that rises in temperature from 50 °F to 86 °F and flows within the tubes at a rate of 68.9 kg s-1. Finding the appropriate thermophysical data and applying the proper equations, you are required to do the following: