As shown in Figure 1, one portion of the hot flue gases is supplied to the steam generator. The steam generator is a shell and tube type of heat exchanger. In this steam generator treated bore water flows through the tubes while the hot flue gases flow in the shell, and steam is produced. The average demand of the steam for other processes within the iron/steel industry is (251) kg/hr at (155) ℃ temperature and 400kPa absolute pressure. Treated bore water is supplied to the steam generator at an average temperature of 20℃. The average pressure drop in the water line of the steam generator is 10kPa. The flue gases enter the shell and tube heat exchanger (steam generator) at a pressure of 110 kPa (Absolute) and a temperature of (252) ℃ and average mass flow rate of (134) kg/min. The average pressure drop in the flue gas side of the steam generator is 5kPa. Flue gases can be assumed to behave as ideal gas and have constant specific heat capacities equal to that of air (Cp=1.005kJ/kg.K and Cv = 0.718kJ/kg.K). The steam generator is insulated, but it still loses on average 6 kW of thermal energy to the surroundings though the outer surface. The outer surface of the steam generator has an average temperature of 54.5 ℃ Determine the rate of entropy generation in the steam generator, in kW/K.
Heat Exchangers
Heat exchangers are the types of equipment that are primarily employed to transfer the thermal energy from one fluid to another, provided that one of the fluids should be at a higher thermal energy content than the other fluid.
Heat Exchanger
The heat exchanger is a combination of two words ''Heat'' and ''Exchanger''. It is a mechanical device that is used to exchange heat energy between two fluids.
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As shown in Figure 1, one portion of the hot flue gases is supplied to the steam generator. The steam generator is a shell and tube type of heat exchanger. In this steam generator treated bore water flows through the tubes while the hot flue gases flow in the shell, and steam is produced. The average demand of the steam for other processes within the iron/steel industry is (251) kg/hr at (155) ℃ temperature and 400kPa absolute pressure. Treated bore water is supplied to the steam generator at an average temperature of 20℃. The average pressure drop in the water line of the steam generator is 10kPa. The flue gases enter the shell and tube heat exchanger (steam generator) at a pressure of 110 kPa (Absolute) and a temperature of (252) ℃ and average mass flow rate of (134) kg/min. The average pressure drop in the flue gas side of the steam generator is 5kPa. Flue gases can be assumed to behave as ideal gas and have constant specific heat capacities equal to that of air (Cp=1.005kJ/kg.K and Cv = 0.718kJ/kg.K). The steam generator is insulated, but it still loses on average 6 kW of thermal energy to the surroundings though the outer surface. The outer surface of the steam generator has an average temperature of 54.5 ℃
Determine the rate of entropy generation in the steam generator, in kW/K. Show all steps of the calculations, including estimating all parameters required to determine the rate of entropy generation.
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