Inviscid and Incompressible flow

Question 1

What flow is the navier stokes equation used for?

Answer 1

Incompressible viscous flow

Question 2

What flow is the bernoulli equation used for?

Answer 2

Incompressible inviscous flow
Rotational flow - along streamline
Irrotational flow - at every point

Question 3

What is the Kelvin theorem?

Answer 3

The circulation around a closed curve consisting of the same fluid elements (streamline) remains constant.

Question 4

What are the 5 elementary flows

Answer 4

Unifrom Flow
Source
Sink
Doublet
Vortex

Question 5

Describe the characteristics of the uniform flow

Answer 5

As the flow satisfies the continuity equation and is irrotational the potential function and steamwise function can be determined. Circulation is ZERO.

Question 6

Describe the characteristics of the source/sink flow

Answer 6

Continuity equation is satisfied everywhere but the centre. Potential function can be found.

Question 7

What is a doublet?

Answer 7

A combination of a source and a sink

Question 8

What is a potential vortex?

Answer 8

A singularity with infinite vorticity with concentric steamlines. The potential function can be calucated if the circulation is known.