H.W.Q1: Air enters a 7m long section of a rectangular duct of cross section 15 cm x 20 cm at 50°Cat an average velocity of 7 m/s. If the walls of the duct are maintained at 10°C, determine (a)the outlet temperature of the air, (b) the rate of heat transfer from the air.Air properties from tables:p=1.127 kg/m³C, =1007 J/kg.°Ck = 0.02662 W/m.°cPr = 0.7255v=1.702×10 m²/sAnswer: (a): Te = 34.2 °C,(b): Q' = 3776 WHint: 1- Use the Logarithmic mean temperature difference relations.2- If: Reer> 2300, in pipes and ducts, the flow is turbulent.T, = 10°CAir duet15 cm x 20 cmAirL-7 m50°C7 m/s

Given:L=7 mArea of duct=15 cm x 20 cmTi=50°CV=7 m/sTs=10° Chydraulic…

Q1: Air enters a 7m long section of a rectangular duct of cross section 15 cm x 20 cm at 50°C at an average velocity of 7 m/s. If the walls of the duct are maintained at 10°C, determine (a) the outlet temperature of the air, (b) the rate of heat transfer from the air. Air properties from tables: C, =1007 J/kg.°C p=1.127 kg/m³ k = 0.02662 W/m.°C Pr = 0.7255 v=1.702×10° m²Is Answer: (a): Te = 34.2 °C, (b): Q' = 3776 W Hint: 1- Use the Logarithmic mean temperature difference relations. 2- If: Recr > 2300, in pipes and ducts, the flow is turbulent. T,- 10°C Air duet 15 cm x 20 cm Air L-7m 50°C 7 m/s

Q1: Air enters a 7m long section of a rectangular duct of cross section 15 cm x 20 cm at 50°C at an average velocity of 7 m/s. If the walls of the duct are maintained at 10°C, determine (a) the outlet temperature of the air, (b) the rate of heat transfer from the air. Air properties from tables: C, =1007 J/kg.°C p=1.127 kg/m³ k = 0.02662 W/m.°C Pr = 0.7255 v=1.702×10° m²Is Answer: (a): Te = 34.2 °C, (b): Q' = 3776 W Hint: 1- Use the Logarithmic mean temperature difference relations. 2- If: Recr > 2300, in pipes and ducts, the flow is turbulent. T,- 10°C Air duet 15 cm x 20 cm Air L-7m 50°C 7 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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