Steamline, Pathline, Streakline

[harvhk852]

This topic is about streamlines, pathlines and streaklines. Please could you see if you could help me out, only if you answer one of the questions would be a great help. Thanks a lot

1) When are these line identical??

2) Is the visualied line a streamline, pathline or a streakline in the following cases.

a) The stream plume released from a vent pipe at a power plant.

b) The vapour trail of a jet airplane.

c) The smoke released from a source upstrean of a model in a wind tunnel experiment. The wind tunnel flow is steady.

d) A nuetrally bupyant helium balloon carried in the wind.

 

[FredGarvin]

They are identical in steady flows, i.e the velocity at a point does not change.