Incomp

Question 1

What are the kutta conditions

Answer 1

Circulation around an airfoil at an angle such that flow leaves trailing edge smoothly.

If trailing edge angle is finite then the rear stagnation point is located at trailing edge.

If trailing edge is cusped and angle is zero then velocity leaving top and bottom are equal in magnitude and direction

Question 2

What is a stream function

Answer 2

Flow rate between streamlines

Question 3

What is velocity potentiak

Answer 3

Normal to streamlines

Question 4

Define boundary later thickness

Answer 4

The thin transition layer between the wall and flow of the fluid

Question 5

Define boundary layer momentum thickness

Answer 5

Reduction in momentum of flow due to boundary layer

Question 6

Define boundary layer displacement

Answer 6

Distance surface should move to reduce flow equivalent to the real effect of the boundary layer

Question 7

Why do turbulent boundary layers have higher skin friction drag than laminar

Answer 7

The turbulent shear stresses are higher than laminar due to turbulent fluctuations

Question 8

Define circulation

Answer 8

Movement of flow around an object

Question 9

Define vorticity

Answer 9

Describes a spinning motion of a fluid at a single point

Question 10

Why does experiment show stall and 2D and 3D doesn’t

Answer 10

In experimental flow separation is considered. The separation would have increased to the point it would hinder the wings ability to produce lift resulting in stall.