PHEP 12 Flashcards
In most hydroelectric developments the head and water flow will:
Fluctuate
Intake design has a large effect on:
velocity
volume
head
all three
A partially clogged trash rack will:
cause a decrease in the effective head
Wood-stave pipe would probably not be used for
heads above 500 feet
An open conduit system implies:
the presence of a free surface
The best canal cross-section from a hydraulic point of view is defined as:
the one that has a minimum wetted Perimeter
The least efficient type of high-line conduit is that type which:
has the greatest effect on the available head
Steel pipe is used more extensively than any other type of pipe for penstock construction because:
of the degree of flexibility it offers in satisfying design criteria in all of the above areas
One of the major advantages of using a pressure tunnel in a power conduit system is that:
it permits full use of the available head
Positive water-hammer pressure caused by a sudden decrease in the demand for water can be eliminated by
relief valve
a pressure-regulator
a surge tank
any one of the above
Negative water-hammer pressure is created by:
a sudden increase in the demand for water
Which of the below conditions would probably not cause the water level in the riser of a differential surge tank to fall?
a load rejection
Pumped storage type of hydroelectric developments implies a capability for:
improving load factors on inter-connected power system steam plants
providing a wider range of power system reserve capacity
improved peak load operation
all of the above
The best hydraulic rectangular cross-section occurs when : (b=bottom width, y=water depth)
y=b/2
Penstock velocities may range from:
6 to 20 ft/sec
