What is the seepage velocity?
Seepage velocity is the velocity of groundwater calculated from Darcy’s law. Seepage velocity is not the actual velocity of the water in the pores, but the apparent velocity through the bulk of the porous medium.
What is discharge velocity and seepage velocity?
Discharge velocity is the volume of water flowing in unit time across the unit cross section perpendicular to the direction of flow. Seepage flow is the volume of of water flowing in unit time across the unit surface area of available voids. seepage velocity is the real velocity of water through the soil.
What is Darcy’s velocity?
v = -K(∆h/∆l) This is the Darcy velocity (or Darcy flux) which is defined as the flow per unit cross sectional area of the porous medium. Since you have a porous media the water must move through the pores, around the solid particles, at a speed greater than the flux.
How is seepage calculated?
Average seepage velocities can be determined by dividing the seepage discharge within a flow channel by the area of the flow channel (distance between flow 1 ines times a unit length of structure). The total seepage is equal l y divided between a1 1 flow channels.
What is the difference between permeability and seepage?
Permeability, as the name implies (ability to permeate), is a measure of how easily a fluid can flow through a porous medium. Flow of water through soils is called seepage. Seepage takes place when there is difference in water levels on the two sides of the structure such as a dam or a sheet pile as shown in Fig.
What is the formula of discharge?
Discharge = V x D x W If length is measured in feet and time in seconds, Discharge has units of feet3/sec or cubic feet per second (cfs). Depth times Width gives the cross-sectional area.
What is seepage pressure?
Seepage pressure the pressure exerted by water on soil through which it percolates is known as seepage pressure (Ps) it is given by: Ps=h∗ηw. Ps=hL∗L∗ηw. Ps=iLηw. Quicksand condition: The seepage is responsible for the phenomenon of quicksand this condition occurs when the flow takes place in an upward direction.
What is Darcy’s Law in soil mechanics?
From Wikipedia, the free encyclopedia. Darcy’s law is an equation that describes the flow of a fluid through a porous medium. The law was formulated by Henry Darcy based on results of experiments on the flow of water through beds of sand, forming the basis of hydrogeology, a branch of earth sciences.
What is interstitial velocity?
Interstitial Velocity is the speed at which the molecules of water are progressing in the direction of movement.
Why is Darcy’s law important?
Darcy’s Law works because the driving forces (gravity and pressure) in the fluid are balanced by the viscous resistance of the medium. – Head drop with distance is therefore linear in our simple system. – If inertial forces become important, the head drop is no longer linear.
How do you calculate groundwater velocity?
The equation for calculating ground water velocity is: V= KI/n. In this formula V stands for “groundwater velocity,” K equals the “horizontal hydraulic conductivity,” I is the “horizontal hydraulic gradient,” and n is the “effective porosity.”
What is seepage of soil?
Seepage, in soil engineering, movement of water in soils, often a critical problem in building foundations. Seepage depends on several factors, including permeability of the soil and the pressure gradient, essentially the combination of forces acting on water through gravity and other factors.
What is seepage head?
At point A, the pore water pressure (u) can be measured from the height of water in a standpipe located at that point. The height of the water column is the pressure head (hw). As seepage velocity in soils is normally low, velocity head is ignored, and total head becomes equal to the piezometric head.