Area 2 - Open Channel

Question 1

a conduit in which liquid flows with a free surface

Answer 1

open channel

Question 2

a type of flow having a free surface and subjected to atmospheric pressure.

Answer 2

open channel flow

Question 3

a type of flow confined in a closed conduit, has no free surface and exerts no direct pressure but hydraulic pressure only

Answer 3

pipe flow

Question 4

if the depth of flow does not change or if it can be assumed to be constant during the time interval under consideration

Answer 4

steady flow

Question 5

it is a flow that changes with time

Answer 5

unsteady flow

Question 6

if the depth of flow is the same at every section of the channel

Answer 6

uniform flow

Question 7

uniform flow is also referred to as _____. fundamental type of flow in open channels hydraulics

Answer 7

steady uniform flow

Question 8

if the depth of flow changes along the length of the channel

Answer 8

varied or non-uniform flow

Question 9

varied or non-uniform flow is also known as ______, where water runs in or out along the course of flow.

Answer 9

spatially varied or discontinuous flow

Question 10

example of varied or non uniform flow

Answer 10

roadside gutters, side-channel spillways, washwater trough in filters, effluent channels around sewage-treatment tanks

Question 11

specific energy equation (Froude no. = 1)

Answer 11

critical flow

Question 12

factors that affect open channel flow

Answer 12

viscosity, gravity

Question 13

together with gravity, they are the factor that basically affect open-channel flow

Answer 13

viscosity

Question 14

what are the types of flow in terms of the effect of viscosity relative to inertia.

Answer 14

laminar, turbulent, transitional

Question 15

water particles appear to move in definite, smooth paths, or streamlines; and extremely thin layers of fluid slide over adjacent layers

Answer 15

laminar

Question 16

viscuous forces are weak relative to inertial forces; water particles move in irregular paths which are neither smooth nor fixed

Answer 16

turbulent

Question 17

the effect of viscosity relative to inertia can be represented by the

Answer 17

reynold’s number

Question 18

if the depth of flow is taken as the characteristic length, R < 500

Answer 18

laminar flow

Question 19

if the depth of flow is taken as the characteristic length, R > 2000

Answer 19

turbulent flow

Question 20

if the depth of flow is taken as the characteristic length, 500 < R > 2000

Answer 20

transitional flow

Question 21

Its effect on the state is represented by a ratio of inertial forces to gravity forces, given by Froude number

Answer 21

gravity

Question 22

the value of F, if the the flow is critical

Answer 22

F = 1

Question 23

the value of F, if the flow is supercritical (inertial force is dominant; the flow is rapid, has high velocity, and has torrential shooting)

Answer 23

F > 1

Question 24

the value of F, if the flow is subcritical (gravity force is more pronounced; the flow is tranquil, has low velocity, and is streamlined)

Answer 24

F < 1

Question 25

a kind of open channel that includes all watercourses that exist naturally on the earth. eg. underground stream, rivulets

Answer 25

natural

Question 26

a kind of open channel that is constructed or developed by human. eg. flumes, power canals, chutes, spillways

Answer 26

artificial

Question 27

usually a long and mild-sloped channel built in the ground which may be lined or unlined

Answer 27

canal

Question 28

it is a channel made of wood, metel, or concrete supportedabove the surface of the ground to carry water across a depression

Answer 28

flume

Question 29

a channel having a steep slope

Answer 29

chute

Question 30

a covered channel of comparatively short length installed to drain water trough a highway and railroad embnkments

Answer 30

culvert

Question 31

comparatively long covered channel used to carry water through a hill or any obstruction on the ground

Answer 31

open-channel tunnel

Question 32

according to channel geometry

Answer 32

prismatic and non-prismatic channel

Question 33

it is the vertical distance of the lowest point of a channel section from the free surface

Answer 33

depth of flow

Question 34

it is the width of channel section at the free surface

Answer 34

top width (T)

Question 35

it is the cross-sectional area of the flow normal to the direction of flow

Answer 35

water area (A)

Question 36

the length of the line of intersection of the channel wetted surface with a cross-sectional plane normal to the direction of flow

Answer 36

wetted perimeter

Question 37

ratio of water to its wetted perimeter

Answer 37

hydraulic radius

Question 38

ratio of water area to the top width

Answer 38

hydraulic depth

Question 39

ratio of the dry weight of soil particles to the weight of an equal volume of water

Answer 39

real specific gravity

Question 40

the moisture content of the soil when the gravitational water has been removed

Answer 40

field capacity

Question 41

these are pipelines built on or near the ground surface that convey water across wide depressions

Answer 41

inverted siphons

Question 42

subsurface drain system wherein laterals join the submain on both sides alternately

Answer 42

herringbone

Question 43

it is the ratio of the volume of voids to the total volume of soil

Answer 43

porosity

Question 44

it is the water retained about individual soil particles by molecular action and can be removed only by heating

Answer 44

hygroscopic water

Question 45

it refers to the composite parts of the irrigation system that divert water from natural bodies of water such as rivers, streams, and lakes

Answer 45

headworks