Difference between revisions of "Flow through perforated pipe"

Revision as of 02:37, 25 February 2018

Manufacturers of perforated pipe are often able to provide the open area (m²) per meter length.

$Q_{max,p}=B\times C_{d}\times A_{o}{\sqrt {2\cdot g\cdot \sum d}}$

Where:_d is the coefficient of discharge (0.61 for a sharp edged orifice),

B is the clogging factor (between 0.5 to calculate a for matured installation and 1 to calculate a new perfectly performing BMP),
C_d is the coefficient of discharge (usually 0.61 for the sharp edge created by relatively thin pipe walls),
A_o is the total open area of the perforated pipe (m²/m),
g is acceleration due to gravity (m/s²)
Σ d is the total depth of bioretention components over the perforated pipe (mm) (e.g. ponding/mulch/filter media/choker layer),

@@ Line 2: / Line 2: @@
 <math>Q_{max, p}=B\times C_{d}\times A_{o}\sqrt{2\cdot g\cdot \sum d}</math>
-{{Plainlist|1=Where:
+{{Plainlist|1=Where:<sub>d</sub>'' is the coefficient of discharge (0.61 for a sharp edged orifice),
-*''K<sub>m</sub>'' is the hydraulic conductivity of the filter media (mm/hr),
+*''B'' is the clogging factor (between 0.5 to calculate a for matured installation and 1 to calculate a new perfectly performing BMP),
-*''A<sub>p</sub>'' is the area of the practice (m<sup>2</sup>),
+*''C<sub>d</sub>'' is the coefficient of discharge (usually 0.61 for the sharp edge created by relatively thin pipe walls),
-*''d<sub>p</sub>'' is the depth of ponding (mm),
+*''A<sub>o</sub>'' is the total open area of the perforated pipe (m<sup>2</sup>/m),
-*''d<sub>m</sub>'' is the depth of the filter media (mm), and
+*''g'' is acceleration due to gravity (m/s<sup>2</sup>)
 *''Σ d'' is the total depth of bioretention components over the perforated pipe (mm) (e.g. ponding/[[mulch]]/[[filter media]]/[[choker layer]]),
 }}