Parallel Duct Pressure Loss
Parallel Duct Pressure Loss
(OP)
I am trying to model flow through an electronics cabinet as if the flow channels were ducts. The flow follows a path similar to this:
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with the horizontal lines acting as Ts in the duct. How do you calculate the total pressure loss of the system in order to achieve a system characteristic curve?
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with the horizontal lines acting as Ts in the duct. How do you calculate the total pressure loss of the system in order to achieve a system characteristic curve?





RE: Parallel Duct Pressure Loss
RE: Parallel Duct Pressure Loss
P = R*q^2
P is pressure drop, kPa
R is resistance, kPa/(l/s)^2
=r*l
r is unit res,
kPa/m/(l/s)^2
l is length, m
q is flow, l/s (theory kg/s!!)
For pipes look up pressure drop in kPa/m versus flow in l/s (~kg/s!) and calculate r as above (r=P/q^2).
For fittings either use equivalent length of pipe (but this varies with flow and pipe size) or use Kv (m^3/h @ 100 kPa) as R = 1296/(Kv^2).
Series resistances,
Rt = R1 + R2
Parallel resistances,
Rt = (R1*R2)/(sqrR1 + sqrR2)^2
I hope this helps!!
Brian