Changes

Jump to navigation Jump to search
Line 49: Line 49:     
==Calculate drawdown time==
 
==Calculate drawdown time==
   
[[file:Hydraulic radius.png|thumb|Three footprint areas of 9 m<sup>2</sup>.<br>
 
[[file:Hydraulic radius.png|thumb|Three footprint areas of 9 m<sup>2</sup>.<br>
 
From left to right x = 12 m, x = 14 m, and x = 16 m]]
 
From left to right x = 12 m, x = 14 m, and x = 16 m]]
The 3 dimensional equations make use of the hydraulic radius (''P''/''x''), where ''x'' is the perimeter (m) of the facility. <br>
+
To calculate the time (''t'') to fully drain the facility:
Maximizing the perimeter of the facility directs designers towards longer, linear shapes such as [[infiltration trenches]] and [[bioswales]]. 
+
:<math>t=\frac{V_{R}A_{p}} {q'P}ln\left [ \frac{\left (d+ \frac{A_{p}}{P} \right )}{\left(\frac{A_{p}}{P}\right)}\right]</math>
   −
To calculate the required depth:
+
This 3 dimensional equation makes use of the hydraulic radius (''A<sub>p</sub>''/''P''), where ''P'' is the perimeter (m) of the facility. <br>
:<math>d=a[e^{\left ( -bD \right )} -1]</math>
+
Maximizing the perimeter of the facility directs designers towards longer, linear shapes such as [[bioswales]]
Where
  −
<math>a=\frac{A_{p}}{x}-\frac{i I}{A_{p}q'}</math>
  −
and
  −
<math>b=\frac{xq}{nP}</math>
  −
 
  −
The rearrangement to calculate the required footprint area of the facility for a given depth is not available at this time. Elegant submissions are invited.
  −
 
  −
To calculate the time (''t'') to fully drain the facility:
  −
<math>t=\frac{V_{R}A_{p}} {q'P}ln\left [ \frac{\left (d+ \frac{A_{p}}{P} \right )}{\left(\frac{A_{p}}{P}\right)}\right]</math>
      
[[category: modeling]]
 
[[category: modeling]]
 
[[category: infiltration]]
 
[[category: infiltration]]
8,255

edits

Navigation menu