THE FLOW OF WATER IN DRAIN TILE. 



43 



60 



* 50 



40 



.8 



.5 



Depth ofF/otv§ 

 .6 .7 .8 



1.0 



CONCRETE TILE 



-*- 



6API653 



Equation ofl/neK=S/.26f^J 



Fig. 3.— Relation of coefficient K to depth of flow in formulae 46-51. 



Depth of F/ow % 

 .6 .7 .8 



1.0 



















^"VJ 



: 



: 

















) 



c 











CON 



CRETI 



: til 



> 

 .E 



c ^ 



t > 



< 





I 

 I 



5 



.s 



Equation of Line oc =.£S8l\j-) 



Fig. 4. — Relation of exponent of D to depth of flow in formulae 46-51. 



The exponent of s in all cases is very nearly 0.5, while the constant 

 K also varies but little. Following the same method as before (see 

 text-figs. 3 and 4) to obtain the formula for any depth of flow, 



Z=51 



and 



o; = 0.5581 



® 



(I \— 0.4601 



Thus, the equation for any depth of flow in concrete tile is 



0.5581 



//7\0-01653r~ ~]/d\0-4 



F=51.26Qy \d\Kb) 



(52) 

 (53) 



(54) 



