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Hi,

The location is room 819 NHA.

The times for the examination will be

10.15 Lars

10.50 Ole Petter

11.25 Michal Jan

12.00 Jacob L

12.35 Kei

13.10 Jacob H

You will have 15 minutes for the presentation of your project, and then another 15 minutes with questioning.

I will get back to you soon regarding location.

The exam will be held on Thursday 9/12, and a more detailed schedule will be posted on Wednesday.

For the presentation, you have 15 minutes for the final project followed by 15 minutes of questions from the syllabus. Power-point, Keynote, PDF or anything else that works is ok. I will have a Mac hooked up and you can either send me the presentation, bring a usb or your own laptop.

The presentation should start with a project description. It is difficult to give general advice, but briefly it is your responsibility to make the presentation as clear and concise for the external sensor as possible. Emphasise what you have done, both why and how you have done it the way that you have. Explain the results. Model sensitivity, mesh sensitivity and sensitivity of numerical methods are relevant topics for most projects.

I'm not sure about time yet. Please let me know if you have some preference.

I will from now on be in room 919 on Fridays, but not Mondays. If you need additional help, please come see me in my office, or send an email.

The final lecture on chapter 11 has been moved to Friday 29/10. That means no lecture tomorrow Monday 25/10. Work on the mandatory assignment, and please come and see me in my office to talk about your project.

I have now finished 4 hours of turbulence lectures. Turbulence is not really syllabus for this course, but a required background. Still, some useful references are

• Chapter 3 in the CFD book
• https://mikaem.github.io/MEK4300/content/chapter6/turbulence.html
• http://www.turbulence-online.com/Publications/Lecture_Notes/Turbulence_Lille/TB_16January2013.pdf
• https://github.com/OpenFOAM/OpenFOAM-dev

I don't expect you to read all these references, they are just ment to help. Note that the openfoam source code contains important references for the turbulence models that are implemented. For example, the k-epsilon model implements a version given by references in the header file.

The mandatory exercise should be submitted by the end of Friday, November 5th. Approval of the mandatory exercise is required for access to the final oral exam.

The last part of this course is a CFD project. You need to decide on a, preferably relevant, project, and present to me a project description of maximum two pages. The project description should be ready by 29/10 the latest.

The project description should contain enough information about your project that an external examiner can read it and clearly understand what you want to do. Describe the physical domain and the equations that are to be solved. Describe the numerical methods to be used. And describe what it is that you are trying to do. A typical project is to run simulations for some benchmark case and compare different numerical methods to each other, and to experimental data (if they exist). In that case it is important to give proper reference to such data.

The oral exam will take place in week 49. If you have some other exam that week I need to know and hopefully I can plan around it. Please send me an email as soon as possible and I will try to fix the date. If I do not hear from you I will assume that any day is fine.

This week there are no new assignments, and Friday there will be a regular lecture on turbulence modelling.

by Jacob Henrik

(0.221212, 0.327101)

Still only correct in the first two digits, though.

I have received a first very good attempt at the price:

Jacob Henrik: (0.222041, 0.328736)

which is correct in the first two digits for both x- and y-directions. Jacob used Fluent to do the calculations. 

The competition is still open:-)

Next week there is no teaching due to høstferie. However, you can still work and I have an additional assignment for you:-)

Compute the regularized lid driven cavity problem. This problem is defined for a square domain [-1, 1]x[-1, 1] and sets the x-velocity of the top lid to (1-x)**2*(1+x)**2. As such there is no discontinuity in the two upper corners. See, e.g., "A study of the regularized lid-driven cavity’s progression to chaos": https://www.sciencedirect.com/science/article/pii/S1007570418303575

Find the location of the center of the main vortex in the flow for Re=250, where the viscosity is calculated as 2/Re. The first that can tell me the location to within 5 digits of accuracy wins a special price:-) (I already know the answer.)

OpenFoam hint: The center of the vortex is located at the same place as the minimum value of the stream function, and you can compute stream functions using the postProcess tool. Also, you ca...

You should start working on this once you have completed the first few OpenFOAM tutorials.

Implement a backwards facing step case in OpenFOAM. Use the icoFoam solver, an expansionfactor of 2 and Re=200 (laminar) and Re=1000 (unstable, turbulent?). See, e.g., this link

For Re=1000 the default numerical scheme in OpenFoam should result in an unstable solution and wiggles. Find an appropriate scheme that removes the wiggles (upwind/TVD).

I am not in town this Friday. However, you should still work on implementing example 5.1, all three cases. Try to replicate figures 5.5 and 5.6 from the book. If you have any questions, please send me an email and I will try to help.

Hi

Welcome to this course on Computational Fluid Dynamics! We will start next week with chapter 4 of our syllabus, `An introduction to Computational Fluid Dynamics - the finite volume method`. Unfortunately, we have not been handed the best of lecture times - Mondays 08.15-10.00 and Fridays 10.15-12.00, where Mondays will be used for lectures and Fridays for exercises. However, we will have to try and make the best of it. In the first few weeks we will only do relatively simple exercises of one-dimensional problems using (preferably) Python for programming. After a while we will turn to more complicated real problems, real geometries and real CFD!

Looking forward to see you on Monday!

Mikael