Which property is a characteristic of a turbulent flow? a. Layers flow without mixing b. A...
Which property is a characteristic of a turbulent flow?
a. Layers flow without mixing
b. A tapered velocity profile in a tube
c. smooth flow
d. Small eddies and mixing between layers
Homework Answers
Ans is. D. Small eddies and mixing between layers
- The most important characteristic of turbulent motion is the fact that velocity and pressure at a point fluctuate with time in a random manner.
- Turbulent flow is diffusive and dissipative .
In general, turbulence brings about better mixing of a fluid and
produces an additional diffusive effect. Such a diffusion is termed
as "Eddy-diffusion ".( Note that this is different from molecular
diffusion)
At a large Reynolds number there exists a continuous transport of energy from the free stream to the large eddies. Then, from the large eddies smaller eddies are continuously formed. Near the wall smallest eddies destroy themselves in dissipating energy, i.e., converting kinetic energy of the eddies into intermolecular energy
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Which property is a characteristic of a turbulent flow?
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