June 20, 2018, 17:13
|
Sand dunes formation
|
#1
|
New Member
Carlos A. Alvarez
Join Date: Mar 2018
Posts: 1
Rep Power: 0
|
Hi,
I am modeling the formation of sand patterns in a rectangular cross-section flume, through a CFD/DEM approach. I am using CFDEM, an open source code that uses OpenFOAM 5.x to solve the continuous phase. I did some laminar simulations, i.e., without a turbulence model, and I got good results when they were compared to my experimental results, but my experiments were in a turbulence regime (between 11000 and 17000 Re numbers). So, my next step was to implement a turbulence model. Until now, I have employed kappa-epsilon and kappa-omega models. In all cases, even with y^+ of the center of the first cell ~ 2, the turbulence simulations produced "strange" results. After a certain time that my simulation starts, the particles start moving as "solid body" in the streamwise direction, without rotation as it would be expected. I have read a right amount of information (in both forum and the user manual) on how to implement the turbulence, and I am confident that my initial setup accomplishes with the requirements for a good simulation (at least I believe that). I would have liked attached two gif animations but I could not by their sizes (around 400 KB). I truly appreciate if anybody could give some help to explain, why the laminar case works better than the turbulent one.
Best,
Carlos
|
|
|