Deck 6: Open Channel Hydraulics

Question 1

Supercritical flow occurs when F is ____.

A)greater than 1
C)equal to 1
B)less than 1
D)equal to 0

Answer 1

A

Question 2

The slope of the channel bottom is defined as the vertical fall divided by the horizontal run of the bottom.

Answer 2

True

Question 3

For a rectangular channel, the Froude number is defined as ____.

A) $\frac { v } { \sqrt { g D } }$
B) $\sqrt [ 3 ] { \frac { Q ^ { 2 } } { T ^ { 2 } g } }$
C) $D + \frac { v ^ { 2 } } { 2 g }$
D) $\frac { a } { T }$

Answer 3

$\frac { v } { \sqrt { g D } }$

Question 4

The ___________________ is the distance along the channel cross section that is in contact with the flowing water.

Question 5

What is the hydraulic radius of a channel?

A)cross-sectional area divided by wetted perimeter
B)area of a cross section of flowing water
C)distance from the bottom of a channel to the top of the flowing water
D)the inverse of the wetted perimeter

Question 6

The velocity of the water at critical depth is called ____.

A)subcritical velocity
C)critical velocity
B)supercritical velocity
D)normal velocity

Question 7

When a channel has a slope that causes ____________________ depth to coincide with critical depth, the slope is called critical slope.

Question 8

The most common occurrence of ___________________ depth is in gradually varied flow, in which the flow depth varies over a certain distance due to a change in one or more of the channel attributes.

Question 9

When water flows in a uniform channel, after an initial transition, it reaches and maintains a constant velocity and constant depth called ____________________ depth

Question 10

A(n) ____________________ channel is one that maintains a constant shape and slope.

Question 11

When F = 1, flow is critical.

Question 12

Maximum velocity occurs just below the free surface in the center of a channel.

Question 13

Critical depth results in a maximum value of specific energy.

Question 14

The height of flow is the vertical distance from the bottom of the channel to the water surface.

Question 15

Slope can be expressed as a percentage by multiplying by ____.

A)1
C)100
B)10
D)1,000