Cheg 355 - Lecture Notes - Sept. 30, 2003
Announcements
As per requests, the exam will be two weeks from today on October 14. Also
we have shifted the homework due dates. Problem set 5 which had been due today
can be turned in anytime between now and October 7, while problem set 6 (linked
into Thursday's notes) is due just before break on October 16. Good luck on
all your exams!
Class notes
Scanned Notes
The main points of the lecture were
- Poiseuille Flow and Couette Flow
Goals:
After this class you should be able to:
- Solve flow problems in cylindrical coordinates.
- Identify the centrifugal and coriolis force terms in the momentum equations and know where they are important.
Reading
- The class notes.
- WWWR, chapter 9; BS&L, chapter 3
- Multi-Media Fluid Mechanics: Work through Dynamics:Reynolds Number:Inertia and Viscosity.
Although you should work through the whole section, be sure to go through the last
part (A Gallery Of Flows) which may give you some ideas for your demonstrations!
Additional Readings:
The transition to turbulence for Poiseuille flow was first identified and described by
Osborne Reynolds, a famous fluid mechanic of the late 19th century. He showed that
the transition occurred when the ratio of inertial forces to viscous forces exceeded a
critical value, now named the Reynolds number in his honor. The importance of this
parameter to fluid mechanics cannot be overstated, since as we shall see it controls
the flow pattern found in nearly every geometry. A good biography of Reynolds
may be found here.
A description of how Reynolds determined this dimensionless group is given
here.
Demonstration:
Poiseuille's Law and the Milkshake.
David.T.Leighton.1@nd.edu