What is a cross section of a channel?

A channel section is defined as the cross section taken perpendicular to the main flow direction. Referring to Fig. 1.1 the geometric elements of an open channel are defined as follows: Flow depth, y. It is a vertical distance from the channel bottom to the free surface.

What are the most efficient cross sections in an open channel?

The corre- sponding cross section will be the most efficient cross section. A circle has the least perimeter for a given area of any geometric shape. Semi-circular open channel will discharge more water than any other shape (assuming that the area, slope and surface roughness are the same).

What is a stream cross section?

Cross-sectional area (A in the formula) is the product of stream width multiplied by average water depth.

What is the most efficient channel section?

The highest component of total construction cost is of lining & if the perimeter is kept minimum the cost of lining will be minimum, hence it will be the most economical section….Detailed Solution.

Section Condition
Triangular θ = 45°
Trapezoidal R = y/2 θ = 60° Most efficient trapezoidal section is half hexagone

What are the different types of of channel section?

The rolled steel Channel sections are classified into four categories as per ISI, namely, Indian Standard Joist/Junior Channels ISJC. Indian Standard Light Channels ISLC. Indian Standard Medium Weight Channels ISMC.

What do you understand by best hydraulic channel cross-section?

The best hydraulic channel section is determined by using Lagrange’s method of undetermined multipliers. For a given flow, roughness coefficient, and longitudinal slope, this method optimizes the channel section by minimizing the wetted perimeter (or the cross‐sectional area) subject to a constraint.

Why trapezoidal section is used for canal?

1)Heavy rains – The trapezoid has its width gradually increasing towards the top. In case of heavy rains , since the water level increases ,the trapezoid geometry ensures that the channel doesn’t overflow as the water is accommodated in the larger areas at the top of the trapezoid.

How is the best hydraulic channel cross section define?

Detailed Solution A channel section is said to be economical when it can pass a maximum discharge for a given cross-sectional area, resistance coefficient, and bottom slope. A section of a channel is said to be most economical when the cost of construction of the channel is minimum.

What are the different types of water flow?

Within a stream channel, three types flow can be observed:

  • Laminar flow – water flow in the stream is not altered in its direction. Water flows as parallel molecular streams.
  • Turbulent flow – water flows as discrete eddies and vortices. Caused by channel topography and friction.
  • Helical flow – spiral flow in a stream.

Which cross-section of beam is most economical?

Beam theory shows that the I-shaped section is a very efficient form for carrying both bending and shear loads in the plane of the web.

What are the different types of steel sections?

Different Forms of Rolled Steel Sections

  • Angle sections.
  • Channel sections.
  • T- sections.
  • I-sections.
  • Round bars.
  • Square bars.
  • Flat bars.
  • Corrugated sheets.