Load & DesignPregunta 16 de 110
Air velocity in a duct is calculated by dividing airflow (CFM) by what?
a.The duct length
b.The cross-sectional area of the duct in square feet
c.The static pressure
d.The temperature difference
Explicación
Velocity in feet per minute equals CFM divided by the duct cross-sectional area in square feet. Excessive velocity causes noise and high friction losses, while too little velocity can reduce throw and mixing. Designers balance velocity against static pressure limits.
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