CE444-APPLIED HYDRAULICS
FALL 2009
FINAL EXAM
MONDAY, DECEMBER 14, 2009, 0800-1000
Name: ______________________ Red ID __________________ Grade: _________
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Instructions: Closed book, closed notes. Use engineering paper.
When you are finished, staple your work in sequence (1 to 5),
and return this sheet with your work.
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- (20%) A planned reservoir has a total capacity of 5 million cubic meters (5 hm3).
The catchment drainage area is 200 km2.
The mean annual runoff in the basin is 500 mm.
The sediment yield is 1,350 Metric tons/km2/yr.
The specific weight of sediment deposits is estimated at 13,000 N/m3.
The sediments are coarse grained.
How long will it take the reservoir to fill up to 80% capacity?
Use five increments of reservoir capacity (from 5 hm3 to 0 hm3).
- (20%) Calculate the diameter of a concrete culvert to pass the 50-yr flood, with Q50 = 265 cfs.
The inlet invert elevation is z1 = 180 ft.
The natural streambed slope is So = 0.01. The tailwater depth above the outlet invert is y2 = 4.2 ft.
The culvert length is 250 ft.
The roadway shoulder elevation is 196 ft.
Assume a 2-ft freeboard. Assume a circular concrete culvert (f = 0.018, n = 0.012), and square edge with headwalls.
- (20%) Given Vo = 8 fps and VA = 12 fps at po = 20 psia,
calculate the pressure coefficient Cp and the velocity
Vo that will just begin to cause cavitation in the slot. Assume T = 70oF.
- (20%) Given the system shown below, what is the discharge Q (m3/s) and corresponding head H (m) at the system operating point? Assume sharp entrance and exit losses. Assume f = 0.018.
The performance curve of the pump is given by: H = 60 - 600 Q2
- (20%) What head ΔH (m) will be developed for an axial-flow pump of D = 0.3 m operating at n = 900 rpm and discharging Q = 100 L/s? What power P (KW) will be required?
The pump dimensionless performance curves are shown below.
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