Hairdryer is an electromechanical device that blows ambient or hot air over damp hair to speed the evaporation of water to dry the hair. To design a hairdryer, it should contain the following basic components: a duct of constant diameter with a few layers of electric coils, a small fan to pull the air in and force it through the heating coils. If the density of air is 1.18 kg/m³ at the inlet and 0.90 kg/m³ at the exit, calculate the percent increase in the velocity of air as it flows through the dryer.

Hairdryer is an electromechanical device that blows ambient or hot air over damp hair to speed the evaporation of water to dry the hair. To design a hairdryer, it should contain the following basic components: a duct of constant diameter with a few layers of electric coils, a small fan to pull the air in and force it through the heating coils. If the density of air is 1.18 kg/m³ at the inlet and 0.90 kg/m³ at the exit, calculate the percent increase in the velocity of air as it flows through the dryer.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.8P

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