Phep Ch.12 Flashcards
In most hydroelectric developments the head and water flow will?
Fluctuate
Intake design has a large effect on?
Velocity, volume and head
A partially clogged trash rack will?
Cause a Decrease in effective head
Wood-stave pipe would probably not be used for?
Pressure conduit
An open conduit system implies?
Presence of a free surface
The best canal cross section from a hydraulic point of view?
Is one that has a minimum wetted perimeter
The least efficient type of high line conduit is the type which?
Has the greatest effect on the available head
Steel pipe is used extensively more than any other type of pipe for penstock construction, why?
It can be riveted, welded, withstand changes in static or dynamic pressures and the degree of flexibility it offers in satisfying design criteria
One of the major advantages of using a pressure tunnel in a power conduit system is that?
It permits full use of available head
Positive water hammer pressure caused by a sudden decrease in the demand for water can be eliminated by?
A relief valve, pressure-regulator, and a surge tank
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 interconnected power system steam plants.
Providing a wider range of power system reserve capacity.
Improved peak load operation
The best hydraulic rectangular cross section occurs when?
Y= b/2
Y - water depth
b - bottom width
Penstock velocities may range from?
6 to 20 ft./sec.
