Changes

Bioretention: Sizing and modeling (view source)

16 bytes added , 6 years ago

m

Line 53: Line 53:

*Begin the drainage time calculation by dividing the area of the practice (''Ap'') by the perimeter (''P'').

*To estimate the time (''t'') to fully drain the facility:

:<math>t=\frac{V_{R}A_{p}}{f'P}ln\left [ \frac{\left (d+ \frac{A_{p}}{P} \right )}{\left(\frac{A_{p}}{P}\right)}\right]</math>

:<math>t=\frac{V_{R}A_{p}}{f'P}ln\left [ \frac{\left (d_{T}+ \frac{A_{p}}{P} \right )}{\left(\frac{A_{p}}{P}\right)}\right]</math>

{{Plainlist|1=Where:

*''VR'' is the void ratio of the media,

Line 59: Line 59:

*''f''' is the design infiltration rate (mm/hr),

*''P'' is the perimeter of the practice (m), and

*''d'' is the total depth of the practice, including the ponding zone (m).}}

*''dT'' is the total depth of the practice, including the ponding zone (m).}}

This 3 dimensional equation makes use of the hydraulic radius (''Ap''/''P''), where ''P'' is the perimeter (m) of the facility.

8,254

edits