For homework this week you are asked to solve for the velocity profile in
boundary layer flow along a flat plate with suction - one of the techniques used to
control boundary layer growth and separation. A Physics Today article on the history of Prandtl's boundary layer theory and
experiments is given
here. A really lovely picture of the
effect of suction on boundary layer separation over a wing may be found
here.
Another link at the same site (given
here)
has some interesting examples of experimental planes where the technique was used.
In class we also talked about "TrailerTails", an interesting example of how you can reduce drag on
a truck by delaying boundary layer separation. A picture of one is given
here. These were quite common on the highways for awhile,
but now aren't seen quite as often. They worked great, but... An interesting analysis of how
market forces and technology interacted in this case is given here and is worth a read if you are interested in going into consulting and marketing!
