Fluid Flow, Mass Flow And Transport Of Particles

Question 1

What does the term “Rugosity” refer to?

Answer 1

Rugosity is used to describe the smoothness of the channel.

Question 2

How does the velocity of a fluid affect the carrying capacity? What does adding heat to a fluid do to the carrying capacity?

Answer 2

Changes in velocity either increase or decrease the fluids carrying capacity. If velocity is increased, the fluid is able to move larger particles and entrain grains of sediment.

If heat is added to a fluid flow, the viscosity is decreased which lowers the viscosity and decreases carrying capacity.

Question 3

Draw and describe the different parts of a Hjulstrom Diagram

Answer 3

Top: grain sizes
Y axis: flow velocity (cm/s)
Bottom: grain size
Two curves separating entrainment, deposition, transport as bedload and Erosion and transport

Question 4

Sketch a unidirectional current ripple

Answer 4

You got it!

Question 5

What is Stokes law?

Answer 5

Stokes law is related to settling velocity and graded bedding formation. Proportional to:
~acceleration due to gravity
~grain diameter
~density of fluid v.s density of particles
~viscosity

Result: graded bedding, fining upwards sequence

Question 6

Sketch/interprete a bed form stability diagram

Answer 6

Here’s one

Question 7

What is the difference between a dune and a ripple?

Answer 7

Size