MAE 101A Winter Quarter 2002

Introductory Fluid Mechanics

Winter Quarter 2002

Stefan LLEWELLYN SMITH
EBUII 574
x23475
http://www-mae.ucsd.edu/~sgls

This is the homepage for MAE101A during the Winter Quarter 2002. Last updated: Apr 16, 2002.

Lectures

Lectures: Mondays, Wednesdays and Fridays, 9:05-9:55 am in Center Hall 212. Friday 8:00 am in Center Hall 212: discussion section or lectures. Professor's office hours: Mondays 10-11 am and Wednesdays 10-11 am in EBU II 574. The TA is Aravind Murthy (amurthy@ucsd.edu), office hours Mondays 11 am-1 pm in EBU II 105. The reader is Taryn Catlin.

Required text

Fox and McDonald, Introduction to Fluid Mechanics. 5th Edition, Wiley, 1998.

You may find the CD Rom Multi-media fluid mechanics resource by G.M. Homsy et al. interesting. I have placed it on reserve at the S&E library (call number YED 30). I have asked for a 24 hour checkout period, so you can take use it on a machine outside the library if you don't have a laptop with you. Please don't be selfish with it.

Syllabus

Lecture Schedule and Notes

Jan 7: Chapter I Introduction
Jan 9: Chapter II Continuum description. Velocity field.
Jan 11: Review of vector calculus. Handout on suffices. Quiz solutions.
Jan 11: Kinematic description of flow.
Jan 14: Stress. Viscosity.
Jan 16: Chapter III Fluid statics Pressure.
Jan 18: (Cont.)
Jan 18: Forces on submerged surfaces in fluids at rest.
Jan 21: Martin Luther King, Jr. Holiday.
Jan 23: Fluids in rigid body rotation.
Jan 25: Discussion of HW I.
Jan 25: Chapter IV Conservation laws - integral form Basic laws for a system. System derivatives versus control volume derivatives.
Jan 28: (Cont.)
Jan 30: Control volume with acceleration.
Feb 1: Discussion of HW II.
Feb 1: Conservation of angular momentum. Conservation of energy.
Feb 4: Chapter V Differential analysis of fluid motion Conservation of mass. Streamfunction for 2-D incompressible flow.
Feb 6: Kinematics.
Feb 8: Discussion of HW III.
Feb 8: Conservation of momentum.
Feb 11: Jeopardy! (Review session for midterm.)
Feb 13 (I will be away): Midterm. Bring paper and a stapler! You may bring a single hand-written sheet of notes that you have prepared.
Feb 15 (I will be away): Discussion of HW IV.
Feb 15 (I will be away): Video: pressure fields & fluid acceleration.
Feb 18: President's Day Holiday.
Feb 20: Chapter VI Incompressible inviscid flow Euler's equations.
Feb 22: Discussion of midterm.
Feb 22: Bernoulli's equation.
Feb 25: Examples of steady Bernoulli.
Feb 27: Pressure near stagnation point. Pressure in vortex.
Mar 1: Discussion of HW V.
Mar 1: Bernoulli equation for unsteady flow.
Mar 4: Irrotational flow.
Mar 6: Flow past a circular cylinder.
Mar 8: Discussion of HW VI.
Mar 8: CAPE survey. Chapter VII Dimensional analysis Drag on a sphere.
Mar 11: Video: vorticity.
Mar 13: Non-dimensionalizing the equations of motion.
Mar 15: Discussion of HW VII.
Mar 15: Review of course.
Mar 20, 8:00-11:00 am: Final exam. Bring paper and a stapler! You may bring a single hand-written sheet of notes that you have prepared.

Homework

The homeworks will be worth 20% of the final grade; the lowest homework grade will be discarded. Homeworks will be handed out on Friday, should be handed in the following Friday, and will be returned the Friday after. NO late homework will be accepted.

I Due Jan 18. 2.8, 2.22, 2.34, 2.40. Solutions.
II Due Jan 25. 3.7, 3.15, 3.42, 3.69. The answer to 3.7 at the back of the book is wrong: the correct result is 15.8 mm. Solutions.
III Due Feb 1. 4.14, 4.29, 4.38, 4.41. The answer to 4.14 at the back of the book is wrong: the correct result has an R² in it. Note also that what is computed is what I would call specific momentum flux. It's a good ideal to keep the rho in there for cases where rho is no longer constant. Solutions.
IV Due Feb 8. 4.60, 4.80, 4.124, 4.188. I've had quite a few questions from students, so here are some notes for everybody. 4.60: Remember that the y-component of the velocity of the fluid over the control surface is not constant. There is a trigonometric term. 4.80: The sensible control volume to use is a rectangle with height delta. There is a mass flux out of this control volume, which you have to bear in mind when you calculate the momentum flux out of the control volume. Apologies to the students who pointed this out to me when I doubted them. The important point is that v.dA is non-zero at the top of the control volume. 4.188: No change in u, no dQ/dt. The book states 8 in. Hg vacuum, by which it means 8 inches of mercury below atmospheric pressure. If you use 8 inches of mercury above vacuum, you will get an efficiency of 88%. Solutions.
V Due Feb 22. 5.9, 5.17, 5.26, 5.57. Solutions.
VI Due Mar 1. 6.11, 6.35, 6.41, 6.51. You'll need to think about mass conservation for 6.11. 6.51: It's helpful to use the fact that the streamline that meets the cylinder at theta=0 comes from infinity, where the velocity is U and the pressure is p(infinity).Solutions.
VII (not to be handed in) 6.76, 6.96, 7.18, 7.61. Solutions.

Homework policy: you may discuss problems among yourselves, but what you hand in should be your own work. Copying from other people or from other sources is not allowed. I will monitor this and take action if necessary. After feedback from Taryn, here are guidelines (some of which should be obvious, I hope):

Name (printed clearly) on top of page.
Box in final answers, especially for problems with multiple (a, b & c) parts.
Label multiple parts of problems (a, b & c) clearly.
List assumptions clearly.

Midterm

There will be one midterm on February 13, covering all the material up to and including the lecture on February 8. The midterm will be worth 30% of the final grade. Average: 68. Solution.

Final

The final will count for 50% of the final grade. It will cover all the material lectured during the course. Average: 49. Solution. You may come and look at your finals in my office, but not take them with you.

Grading policy

I remind you of UCSD's policy on academic dishonesty. As I stated in class, I may rescale the three components (homework, midterm, final) separately to arrive at the final grade. Grade breakdown: 4 A+, 12 A, 5 A-, 7 B+, 21 B, 12 B-, 11 C+, 8 C, 12 C-, 5 D+, 2 D, 1 D-.