CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > Siemens > STAR-CCM+

Translation motion not working correctly in Eulerian Multiphase simulation (V.11_02)

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   May 12, 2019, 16:49
Default Translation motion not working correctly in Eulerian Multiphase simulation (V.11_02)
  #1
New Member
 
Mikel Valderrama
Join Date: Apr 2018
Posts: 1
Rep Power: 0
Mikel Valderrama is on a distinguished road
Hi everyone,


I'm currently trying to make some simulations to see the behaviour of a F1 car fuel inside the tank and to also see the different slopes that are generated depending on the velocity of the F1, as well as the sloshing that occurs.


I do not have any kind of errors before starting and during the simulation but instead of watching how the slope is created after applying a 70m/s translation motion that lasts for more than 10s, it seems like the translation motion is only applied at the very start of the simulation and then it dissapears (And, in consequence, the fuel stabilizes until obtaining a flat surface, not making a slope).


Before this project, I did a simulation involving this similar case of VOF Eulerian Multiphase with water inside a cylinder and a rotation velocity and it worked perfectly. However, now I've tried to use a translation motion in the region, tried to change the starting velocity of the region, tried to change the starting velocity of the physics... but it seems like nothing works and I've ran out of ideas.


I have attached some photos with the characteristics that the simulation has and here is also a link to download a video of the simulation: https://www.dropbox.com/s/a2z4yanczt...ation.avi?dl=0


This is a project that I have to present in 2-3 weeks but I still do not have any kind of data and I'm really really nervous.
Attached Files
File Type: txt wow_Copy2.txt (32.8 KB, 6 views)
Mikel Valderrama is offline   Reply With Quote

Old   May 13, 2019, 04:07
Default
  #2
Senior Member
 
Sebastian Engel
Join Date: Jun 2011
Location: Germany
Posts: 566
Rep Power: 21
bluebase will become famous soon enough
Hi Mikel,

Quote:
I do not have any kind of errors before starting and during the simulation but instead of watching how the slope is created after applying a 70m/s translation motion that lasts for more than 10s, it seems like the translation motion is only applied at the very start of the simulation and then it dissapears (And, in consequence, the fuel stabilizes until obtaining a flat surface, not making a slope).
Are you sure constant 70 m/s velocity is the intended boundary condition?
Because your observation would make totally sense. The very first time step accelerates the region from 0 to 70 m/s and after that there is no additional acceleration, is there? This would result in one big slosh followed by dampening of the waves due to gravity (gravitational acceleration).
The fuel only sloshes in its tank when there is any effective acceleration.

The glas of water on a table does not (easily) show that the surface speed of the earth is up to 465 m/s (at the equator), does it?


Best regards,
Sebastian
bluebase is offline   Reply With Quote

Old   May 13, 2019, 06:33
Default
  #3
Member
 
Yogesh Nalam
Join Date: Sep 2012
Location: München, Germany
Posts: 54
Rep Power: 13
nalamyogesh is on a distinguished road
Hello Mikel,

If you want to see a slope inside the tank, can you not just calculate the resultant acceleration (magnitude and direction) due to gravity and acceleration of F1 vehicle and apply it, without any translational velocity.

Cheers!
Yogesh
nalamyogesh is offline   Reply With Quote

Reply

Tags
eulerian multiphase, sloshing tank, translational motion, vof simulation, wall boundary condition

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Natural convection in a closed domain STILL NEEDING help! Yr0gErG FLUENT 4 December 2, 2019 00:04
How to use "translation" in solidBodyMotionFunction in OpenFOAM rupesh_w OpenFOAM Running, Solving & CFD 5 August 16, 2016 04:27
Rigid body motion error when restarting a terminated FSI simulation lingdeer ANSYS 1 May 19, 2013 01:40
Backflow at outlet in a Eulerian gas-solid simulation audrey CFX 10 October 25, 2012 06:15
Need help in Multiphase simulation leonlo1984 FLUENT 0 January 16, 2011 10:28


All times are GMT -4. The time now is 05:04.