Water is to be heated as it flows through a carbon-silicon pipe of inner diameter 3 cm and wall thickness 5 mm. The outer surface of the pipe is wrapped in a thin electric resistance heater. The water enters the piping system at 20°C and this system is to supply water at 70°C at a rate of 10 L/min. a) The heater dissipates energy at a constant rate of 6 kW/m². The backside of the heater is well-insulated so that all this energy diffuses into the flowing water. Determine the required length of the pipe to meet the specified design criteria. Evaluate any necessary properties of water by treating the water as a saturated liquid at an appropriate average temperature. You can find properties of saturated water in Appendix A of the Bergman textbook. Also, you do not need to interpolate between temperatures on the table-simply use the table value that most closely matches your calculations. b) Determine the heater temperature at the end of the pipe assuming there is negligible contact resistance between the heater and the outer pipe wall. You can use a resistance network here but be careful with your units.

Water is to be heated as it flows through a carbon-silicon pipe of inner diameter 3 cm and wall thickness 5 mm. The outer surface of the pipe is wrapped in a thin electric resistance heater. The water enters the piping system at 20°C and this system is to supply water at 70°C at a rate of 10 L/min. a) The heater dissipates energy at a constant rate of 6 kW/m². The backside of the heater is well-insulated so that all this energy diffuses into the flowing water. Determine the required length of the pipe to meet the specified design criteria. Evaluate any necessary properties of water by treating the water as a saturated liquid at an appropriate average temperature. You can find properties of saturated water in Appendix A of the Bergman textbook. Also, you do not need to interpolate between temperatures on the table-simply use the table value that most closely matches your calculations. b) Determine the heater temperature at the end of the pipe assuming there is negligible contact resistance between the heater and the outer pipe wall. You can use a resistance network here but be careful with your units.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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