5. (20 pts) A counter-flow double-pipe heat exchanger is to heat water from 20 °C to 80 °C at a rate of 1.2 kg/s. The he
Posted: Mon May 16, 2022 6:02 am
5. (20 pts) A counter-flow double-pipe heat exchanger is to heat water from 20 °C to 80 °C at a rate of 1.2 kg/s. The heating is to be accomplished by geothermal water available at 160 °C at a mass flow rate of 2 kg/s. The inner tube is thin-walled and has a diameter of 1.5 cm. If the overall heat transfer coefficient of the heat exchanger is 640 W/m², Calculate: (1), the effectiveness of the exchanger; (2) the number of transfer units; (3) determine the length of the heat exchanger required to achieve the desired heating.