Contents - Index


K_damper_opposed



The K_damper_opposed(theta) function returns the resistance coefficient for a damper with opposed vanes given the angle of the vanes.  The coefficient returned should be applied to the upstream damper box velocity.  Note that the function DuctDamperOpposed_CL in the component library implements the dimensional version of this function.  

Inputs: 
theta = vane angle (degree or radian)

Example:
$UnitSystem SI C kPa Degree
$VarInfo DELTAP units=Pa
$VarInfo rho units=kg/m^3
theta = 40 [degree]
K=k_damper_opposed(theta)
vel = 10 [m/s]
P = Po#
T = 20 [C]
F$ = 'Air'
rho=density(F$,P=P,T=T)
DELTAP = rho*vel^2/2*K

{Solution:
DELTAP=895.9 [Pa]
K=14.88
}

Reference:
Dwyer, T., 2017, "Chapter 17: Controls, Dampers, and Valves" in Air Conditioning System Design, Butterworth-Heinemann

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