Author Question: What do Darcy's Law and river discharge have in common? How do they differ? What will be an ideal ... (Read 102 times)

saraeharris · **on:** Jul 15, 2018

What do Darcy's Law and river discharge have in common? How do they differ? What will be an ideal response?

Question 2

What is the difference between velocity and discharge of water through a river channel? What will be an ideal response?

juiceman1987 · **Reply #1 on:** Jul 15, 2018

Answer to Question 1

Both have to do with the volume-rate of flow of water. Darcy's Law pertains to groundwater flow.
River discharge, in contrast, is open-channel flow. The fundamental difference in the equations
governing the two is that Darcy's Law considers the effect of the substrate through which the water is
flowing. Considering this difference, it is not surprising that the rates of groundwater flow are
extremely slow compared to river discharge

Answer to Question 2

Velocity of a river is the speed of travel of water through its channel in, for example, feet per second.
Discharge of a river is the volume-rate of flow through the channel in, for example, cubic feet per
second. Mathematically, you get discharge by multiplying the velocity times an area reflecting the
shape of a two-dimensional cross section through the channel. This results in an answer expressed in
cubic units of volume, such as cubic feet, per second, which is an expression of volume-rate of flow.