2. An air-conditioning system requires air flow at the main supply duct at a rate of 180 m³/min. The average velocity of air in the circular duct is not to exceed 10 m/s to avoid excessive vibration and pressure drops. Assuming the fan converts 70 percent of the electrical energy it consumes into kinetic energy of air, determine the size of the electric motor needed to drive the fan and the diameter of the main duct. Take the density of air to be 1.20 kg/m³. Note that Air Power of the fan is give by: AP = Qy Ah Where: Q = volume flow rate of air m³/s, y = specific weight of air, kN/m³, Ah = pressure head, m Ans: 618 mm 180 m/min 10 m/s

2. An air-conditioning system requires air flow at the main supply duct at a rate of 180 m³/min. The average velocity of air in the circular duct is not to exceed 10 m/s to avoid excessive vibration and pressure drops. Assuming the fan converts 70 percent of the electrical energy it consumes into kinetic energy of air, determine the size of the electric motor needed to drive the fan and the diameter of the main duct. Take the density of air to be 1.20 kg/m³. Note that Air Power of the fan is give by: AP = Qy Ah Where: Q = volume flow rate of air m³/s, y = specific weight of air, kN/m³, Ah = pressure head, m Ans: 618 mm 180 m/min 10 m/s

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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