Exam 2

Question 1

Uniform Flow

Answer 1

No change in velocity over a distance

Question 2

Steady Flow

Answer 2

No change in velocity over time

Question 3

hydraulic Radius

Answer 3

Area/wetted perimeter (Wp)

Question 4

Hydraulic Depth

Answer 4

Area/B (top width)

Question 5

Continuity equation

Answer 5

Q = Q

Question 6

F =?

Answer 6

P*A

Question 7

P = ?

Answer 7

gamma *Hc

Question 8

Normal Depth

Answer 8

The equilibrium depth

Question 9

The equation used to derive manning equations

Answer 9

Chezy Equation

Question 10

Assumptions for uniform depth

Answer 10

a fixed geometry
a fixed flow rate
fixed roughness coefficient
fixed slope

Question 11

What are alternate depths

Answer 11

Two depths with the same specific energy

Question 12

Specific Energy

Answer 12

The total energy in the flow at a cross-section when Function of its kinetic and potential energy terms when you use the bottom of the channel as a datum

Question 13

Critical depth

Answer 13

the depth that critical flow occurs

Question 14

Critical flow

Answer 14

Flow with minimum energy, froudes number = 1

Question 15

Subcritical flow

Answer 15

Froudes <1
Deep water and slow

Question 16

Supercritical flow

Answer 16

Froudes > 1
Shallow water and fast

Question 17

Specific Energy Equation

Answer 17

E = y + (v^2)/2*g

Question 18

Froudes Equation

Answer 18

Fr = V/sqrt(g * D)

D = A / B
B= top width

Question 19

Total Energy H =

Answer 19

E (specific energy) + z (height of ground from datum)

Question 20

Hydraulic choke point

Answer 20

occurs when insufficient energy in a channel to pass over constriction

Water backs up until gains enough energy to pass over at critical depth

Question 21

What causes a hydraulic jump

Answer 21

supercritical flow runs into deep subcritical flow downstream

Question 22

Sequent or conjugate depths

Answer 22

Two depths with the same specific force

Question 23

Specific force equation

Answer 23

F = (Q^2)/(gA) +A(y-bar)
(ft^3)
y bar is the centroid

Question 24

What is a weir?

Answer 24

Is a low damn or overflow structure across an open channel

Weirs force critical depth to occur at the weir

The purpose is to control water and prevent flooding

Question 25

Water flows over the crest of a weir, the depth above this is called the —–?

Answer 25

the head

Question 26

Upstream depth for weirs is?

Answer 26

Y = H + P
Height of weir plus water above the weir

Question 27

H in the weir equation is what?

Answer 27

H is the height of water above the weir

Question 28

how many L in m^3

Answer 28

1000 L in m^3

Question 29

What is the horizontal distance of a broad weir

Answer 29

the Breadth (L)

Question 30

What is a flume

Answer 30

a device that constricts open channel flow for measurement and do not block flow

Question 31

Difference between weir and flume

Answer 31

Flume- water goes through (constricted)
Weir- Water goes over

Question 32

NPDES

Answer 32

National Pollution Discharge elimination system

Legal authoirty to regulate stormwater

Question 33

BMP

Answer 33

Best management practices
pollution prevention, source reduction

Question 34

MS4

Answer 34

Municipal separate storm sewer system

designed for collecting stormwater

not combined sewer

Question 35

NPDES phase 1

Answer 35

large cities with populations over 100,000

Question 36

NPDES phase 2

Answer 36

smaller urbanized areas (trine/angola)

Question 37

Factors that affect stormwater runnoff

Answer 37

topography
precipitation,
infiltration of soil
how wet the soil is
time of concentration
watershed size
land use

Question 38

Watershed

Answer 38

a area that all drains to the same outlet

Question 39

Drainage divide

Answer 39

line that separates drainage areas

Question 40

Methods of watershed delineation

Answer 40

Geographic information systems (GIS)

Drawing drainage divides