Kelvin-Helmholtz and Rayleight-Taylor Instability

Tobi · April 27, 2015, 08:39

Dear Foamer,

as a fun project I simulated the Kelvin-Helmholtz and Rayleight-Taylor Instability during the weekend. Its nothing special but the results can be seen here:

Phenomena: Kelvin-Helmholtz Instability
https://www.youtube.com/watch?v=Nx4boZ2c974

Phenomena: Rayleight-Taylor Instability
https://www.youtube.com/watch?v=Pfo8pGkIOV4

Maybe I will prepare the FOAM files and upload it as a tutorial-case.

kmooney · April 27, 2015, 17:47

Very cool! What did you use to render the animations if you don't mind me asking? Paraview with some low opacity STL's to represent the solid geometries?

Cheers!
Kyle

Tobi · April 27, 2015, 17:50

Hey,

thanks for the feedback. Yes it was paraview and exactly what you mentioned.

hpp10 · March 29, 2017, 06:45

Hello, I am looking for a suitable case for KH-instability and find your amazing case in YouTube. Could you please send me your code for my noncommercial use? Thanks very much!

akidess · March 29, 2017, 08:41

Are your labels correct in case of the Rayleigh-Taylor instability? Typically, the denser fluid is on top (otherwise the interface should be stable).

Tobi · March 29, 2017, 08:46

Hi Anton,

you are right, I made a label mistake and in the comment below it is already mentioned. I added the mistake to the description now. Thanks for your reply.

Houthuys · June 29, 2017, 10:55

Hi Tobias,

May I ask which solver(s) did you use for Kelvin-Helmholtz case? also is the case is available at your website?

Best regards.

Tobi · July 25, 2017, 04:57

Hi,

I was using an own solver based on

pimpleDyMFoam
pimpleFoam

I am not sure right now because it is a long time ago but I guess it was something like that. A mixture model with a passive scalar to distinguish between salt water and normal water and then make the density, viscosity based on that scalar.

Houthuys · July 25, 2017, 10:22

Quote:

Originally Posted by Tobi

Hi,

I was using an own solver based on

pimpleDyMFoam
pimpleFoam

I am not sure right now because it is a long time ago but I guess it was something like that. A mixture model with a passive scalar to distinguish between salt water and normal water and then make the density, viscosity based on that scalar.

Thanks for the information.
Is this solver or case files available somewhere online?

Tobi · July 25, 2017, 10:46

Sorry I was missing that.
No.

April 27, 2015, 08:39	Kelvin-Helmholtz and Rayleight-Taylor Instability	#1
Tobi Super Moderator Tobias Holzmann Join Date: Oct 2010 Location: Bad Wörishofen Posts: 2,711 Blog Entries: 6 Rep Power: 52	Dear Foamer, as a fun project I simulated the Kelvin-Helmholtz and Rayleight-Taylor Instability during the weekend. Its nothing special but the results can be seen here: Phenomena: Kelvin-Helmholtz Instability https://www.youtube.com/watch?v=Nx4boZ2c974 Phenomena: Rayleight-Taylor Instability https://www.youtube.com/watch?v=Pfo8pGkIOV4 Maybe I will prepare the FOAM files and upload it as a tutorial-case. micpage18, sylvester, kmooney and 3 others like this. __________________ Keep foaming, Tobias Holzmann Last edited by Tobi; April 27, 2015 at 11:26.

April 27, 2015, 17:50	Rendering	#3
Tobi Super Moderator Tobias Holzmann Join Date: Oct 2010 Location: Bad Wörishofen Posts: 2,711 Blog Entries: 6 Rep Power: 52	Hey, thanks for the feedback. Yes it was paraview and exactly what you mentioned. __________________ Keep foaming, Tobias Holzmann

March 29, 2017, 06:45	Amazing~	#4
hpp10 New Member 胡丕 Join Date: Apr 2014 Posts: 2 Rep Power: 0	Hello, I am looking for a suitable case for KH-instability and find your amazing case in YouTube. Could you please send me your code for my noncommercial use? Thanks very much!

March 29, 2017, 08:41		#5
akidess Senior Member Anton Kidess Join Date: May 2009 Location: Germany Posts: 1,377 Rep Power: 30	Are your labels correct in case of the Rayleigh-Taylor instability? Typically, the denser fluid is on top (otherwise the interface should be stable). __________________ On twitter @akidTwit Spend as much time formulating your questions as you expect people to spend on their answer.

March 29, 2017, 08:46		#6
Tobi Super Moderator Tobias Holzmann Join Date: Oct 2010 Location: Bad Wörishofen Posts: 2,711 Blog Entries: 6 Rep Power: 52	Hi Anton, you are right, I made a label mistake and in the comment below it is already mentioned. I added the mistake to the description now. Thanks for your reply. __________________ Keep foaming, Tobias Holzmann

April 27, 2015, 17:47		#2
kmooney Senior Member Kyle Mooney Join Date: Jul 2009 Location: San Francisco, CA USA Posts: 323 Rep Power: 18	Very cool! What did you use to render the animations if you don't mind me asking? Paraview with some low opacity STL's to represent the solid geometries? Cheers! Kyle

June 29, 2017, 10:55		#7
Houthuys New Member rik houthuys Join Date: Jan 2017 Posts: 27 Rep Power: 9	Hi Tobias, May I ask which solver(s) did you use for Kelvin-Helmholtz case? also is the case is available at your website? Best regards.

July 25, 2017, 04:57		#8
Tobi Super Moderator Tobias Holzmann Join Date: Oct 2010 Location: Bad Wörishofen Posts: 2,711 Blog Entries: 6 Rep Power: 52	Hi, I was using an own solver based on pimpleDyMFoam pimpleFoam I am not sure right now because it is a long time ago but I guess it was something like that. A mixture model with a passive scalar to distinguish between salt water and normal water and then make the density, viscosity based on that scalar. __________________ Keep foaming, Tobias Holzmann

July 25, 2017, 10:46		#10
Tobi Super Moderator Tobias Holzmann Join Date: Oct 2010 Location: Bad Wörishofen Posts: 2,711 Blog Entries: 6 Rep Power: 52	Sorry I was missing that. No. __________________ Keep foaming, Tobias Holzmann