14.10.2014 Views

Hydraulic Efficiency of Grate and Curb Inlets - Urban Drainage and ...

Hydraulic Efficiency of Grate and Curb Inlets - Urban Drainage and ...

Hydraulic Efficiency of Grate and Curb Inlets - Urban Drainage and ...

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Table 5-2: Empirical equations for grate <strong>and</strong> curb inlets<br />

Inlet Predictive Equation Simplified Form<br />

Type 13<br />

Combination<br />

0.665 2<br />

0.835<br />

2<br />

−1.138<br />

0.665 0.835 −0.606<br />

⎛ ⎞ ⎛V<br />

T ⎞ ⎛V<br />

⎞<br />

E = 0.063 ⎜ ⎟ ⎜ ⎟ E =<br />

−0.473<br />

0.835 −0.<br />

303<br />

⎜<br />

⎝<br />

h<br />

L<br />

⎟<br />

⎠<br />

⎜<br />

⎝<br />

gA ⎟<br />

⎠<br />

⎜ ⎟<br />

⎝ gL ⎠<br />

h<br />

L<br />

T<br />

A<br />

V<br />

g<br />

Equation<br />

5-8<br />

R 2 Average efficiency error (%) Maximum efficiency error (%)<br />

0.895 4.7 22.6<br />

Type 16<br />

Combination<br />

0.573 2<br />

0.756<br />

2<br />

−0.920<br />

0.573 0.756 −0.328<br />

⎛ ⎞ ⎛V<br />

T ⎞ ⎛V<br />

⎞<br />

E = 0.095 ⎜ ⎟ ⎜ ⎟ E =<br />

−0.347<br />

0.756 −0.<br />

164<br />

⎜<br />

⎝<br />

h<br />

L<br />

⎟<br />

⎠<br />

⎜<br />

⎝<br />

gA ⎟<br />

⎠<br />

⎜ ⎟<br />

⎝ gL ⎠<br />

h<br />

L<br />

T<br />

A<br />

V<br />

g<br />

Equation<br />

5-9<br />

R 2 Average efficiency error (%) Maximum efficiency error (%)<br />

0.844 5.1 21.9<br />

Type<br />

R <strong>Curb</strong><br />

E<br />

2<br />

0.545<br />

2<br />

−0.879<br />

−0.328<br />

0.231<br />

⎛V<br />

⎞ ⎛V<br />

⎞<br />

c<br />

= 0.076⎜<br />

⎟ ⎜ ⎟ Sc E =<br />

−0.879<br />

0.545 −0.<br />

334<br />

⎜ gh ⎟<br />

⎝ ⎠<br />

⎜ gL ⎟<br />

⎝ ⎠<br />

( ) 0. 231<br />

L<br />

V<br />

h<br />

S<br />

g<br />

Equation<br />

5-10<br />

R 2 Average efficiency error (%) Maximum efficiency error (%)<br />

0.890 5.1 29.1<br />

Observed<br />

1<br />

0.9<br />

0.8<br />

0.7<br />

0.6<br />

0.5<br />

0.4<br />

0.3<br />

0.2<br />

0.1<br />

0<br />

1<br />

1 ft depth<br />

0.5 ft depth<br />

0.33 ft depth<br />

Equal<br />

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1<br />

Predicted<br />

Figure 5-8: Predicted vs. observed efficiency for Type 13 combination-inlet from empirical equation<br />

65

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!