ENV 4561
Fall 2011
Homework # 5
Assigned:
September 29, 2011
Due:
October 6, 2011
1)
(20 Points)
A 12 in. ID diameter pipe is discharging to a holding pond with the discharge end
4.0 ft above the pond water surface.
If the water at depth at the end of the pipe is 8 inches,
what is the flow?
Q = 5.2 cfs
2)
(20 Points)
Find the critical depth of a 16 in. diameter circular pipe with a flow of 8 cfs
d
cr
=
1.12 ft
3)
(20 Points)
A rectangular channel is to be designed for the constant discharge Q = 0.87 m
3
/s
with a width b = 1.2 m and a permissible frictional energy loss per unit length of 8x10
4
m/m.
Assume the roughness of the channel is k = 0.4 cm, the energy coefficient,
α
= 1.0, and the
water temperature is 27
o
C.
a)
Find the normal depth of flow assuming the channel flow is in the Mrange.
d
o
= 0.81 m
b)
Verify the flow range.
MRange
c)
Determine the critical depth and state whether the flow is sub or supercritical
d
cr
= 0.377
m and the flow is subcritical
d)
Had one assume the Blasius flow range (Brange) was applicable, what would the normal
depth be and what would be the error in the predicted depth compared to (a).
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Spring '08
 Heaney
 Inch, Blasius flow

Click to edit the document details