Many members of staff in the department have research interests in fluid mechanics and this course will also lay the foundations for possible future postgraduate work in this discipline.

This course is currently taught by Prof Matthias Heil. This page provides online access to the lecture notes, example sheets and other handouts and announcements.

Please note that the lecture notes only summarize the main results and will generally be handed out after the material has been covered in the lecture.

NOTE: The various links on this page (probably) won't work from the mirrored version on the school's undergraduate course pages. Please go to the original at https://personalpages.manchester.ac.uk/staff/matthias.heil/Lectures/Fluids/index.html before trying to download any of the handouts.

If you have any questions about the lecture, please see me in my office (2.224 in the Alan Turing building), contact me by email ( M.Heil@maths.man.ac.uk) or catch me after the lecture.

Syllabus

• 1. Introduction; overview of the course; introduction to index notation. [2]
• 2. The kinematics of fluid flow: The Eulerian velocity field; the rate of strain tensor and the vorticity vector; the equation of continuity. [3]
• 3. The Navier-Stokes equations: The substantial derivative; the stress tensor; Cauchy's equation; the constitutive equations for a Newtonian fluid. [4]
• 4. Boundary and initial conditions; surface traction and the conditions at a free surface. [1].
• 5. One-dimensional flows: Couette/Poiseuille flow; flow down an inclined plane; the vibrating plate. [3]
• 6. The equations in curvilinear coordinates; Hagen-Poiseuille flow; circular Couette flow. [2]
• 7. Dimensional analysis and scaling; the dimensionless Navier-Stokes equations and the importance of the Reynolds number; limiting cases and their physical meaning; lubrication theory. [3]
• 8. The streamfunction/vorticity equations [2]
• 9. Stokes flow (zero Reynolds number flow) [2]
• 10. High-Reynolds number flow; boundary layers; the Blasius boundary layer. [2]

Assessment:

Anti-cramming policy This course used to have a 20% coursework component, introduced in order to force the students to work continuously. The weekly coursework resulted in a fairly heavy workload during term-time (which the students hated) but made exam revision very easy (which they loved). Overall, the coursework element was perceived to be an excellent feature of the course -- judging by the replies on the student questionnaires handed out at the end of the course. Unfortunately, various constraints made it impossible to continue this very successful setup, facing me with the question of how to get you to work for the course throughout term, rather than adopting the "I don't have to work for this course because I can simply cram at the end of term and revise by looking at past exam papers" attitude that all lecturers (and me in particular) detest. So, here is the deal: You are hereby told (yet again) that it essential to work continuously on the material presented in this (and any other) lecture course. If you don't understand the concepts presented in week 1 you will not understand what I talk about in week 2, etc. The best (only?) way to achieve this is to work through the example sheets before the example/feedback class, to make sure you can bombard me with questions about any issues that you don't understand. There is little point in turning up for the example/feedback class without having looked at the problem sheet beforehand -- there's not enough time to do all the work in class. On each problem sheet I will identify a small number of (sometimes substantial) questions that used to form the coursework. The logic behind the selection of the questions is that they'll force you to understand concepts that are essential to the understanding of subsequent material. The (detailed) solutions to each problem sheet will be made available at some suitable time after the example/feedback class (probably a week later). At that point you should swap your nicely-written-up solutions (written up at least as nicely as if you were to hand them in to me) with another student and mark each other's work. No need for a marking scheme, just check what's right and what's wrong (and why!). In my experience, most students tend to work best in small groups anyway so I don't think you'll have problems finding people to swap work with. If you really have no mates, let me know and I'll find you somebody (we'll do triangular swaps if there's an odd number of students). I can see panic developing: Will the "grade" awarded by your mates "count towards the exam"? No! There won't be a grade. You're simply supposed to give each other feedback, and if there are any disputes, I'm happy to act as judge. In fact, I'll be delighted to go back over material in subsequent example/feedback classes if it turns out that many of you struggled with the same problem (assuming I didn't realise that during the example/feedback class itself). However, I can only do this if I know what you struggled with and this obviously requires you to have done the work. Now that the panic is gone, you'll obviously ask yourself why you should bother with this. Surely it'll be easier to use the example/feedback class to read the metro newspaper and exchange gossip, and then use the tried-and-tested "cramming for the exam" technique to "revise". I obviously can't stop you from doing that but I can assure you that, following the end of term, I will refuse to answer any questions (about the course material or previous exam papers) from students who do not have an (at least nearly) complete set of written-up "coursework", with signs that the work was seen by and discussed with somebody else. If you don't work, I won't either. Final question: "Hang on, you want us to do the questions, write up the answers, exchange them with another student, mark each other's work, and then discuss any mistakes/misconceptions with him/her (and the lecturer)? This will take a lot of time!" Answer: "Indeed -- I expect you to work hard for this course!" If you check the UG handbook you'll find that you're supposed to anticipate at least two hours of private study per lecture hour. Furthermore, whatever time you invest on this during term time, you'll save during the exam revision. (Note that this will free up valuable time to catch up with any past issues of the metro newspaper that you didn't have time to read during the examples class!).

Handouts:

• Handout for Introduction and Chapter 1 (pdf) .
• Example sheet I (pdf) .
• Example sheet II (pdf) .
• Handout for Chapter 2 (Kinematics of Fluid Flow) (pdf) .
• Example sheet III (pdf) .
• Handout for Chapter 3 (Stress, Cauchy's equation and the Navier-Stokes equations) (pdf) .
• Example sheet IV (pdf) .
• Handout for Chapter 4 (Boundary and initial conditions) (pdf) .
• Handout for Chapter 5 (Parallel flow) (pdf) .
• Example sheet V (pdf) .
• Animation of the flow above an oscillating plate.
• Example sheet VI (pdf) .
• Animation of the flow profile in a channel with porous walls and constant transverse velocity. (cf Example sheet V).
• Handout for Chapter 6 (Curvlinear coordinates) (pdf) .
• Copy of OHP transparencies on Scaling and Dimensional Analysis .
• Example sheet VII (pdf) .
• Handout for Chapter 7 (Dimensional analysis and scaling).
• Copy of OHP transparencies on the streamfunction-vorticity equation .
• Handout for Chapter 8 (Streamfunction and vorticity).
• Example sheet VIII (pdf) .
• Flowfield for zero Reynolds number scraping flow .
• Example sheet IX (pdf) .

Please note a few corrections for previous handouts (the files above have already been corrected).

Solutions:

• Solutions for example sheet 1 (pdf) .
• Solutions for example sheet 2 (pdf) .
• Solutions for example sheet 3 (pdf) .
• Solutions for example sheet 4 (pdf) .
• Solutions for example sheet 5 (pdf) .
• Solutions for example sheet 6 (pdf) .
• Solutions for example sheet 7 (pdf) .
• Solutions for example sheet 8 (pdf) .
• Solutions for example sheet 9 (pdf) .