CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > CFX

vof fluid sloshing in tank with rolling tank

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

Like Tree1Likes
  • 1 Post By ghorrocks

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 22, 2016, 02:44
Default vof fluid sloshing in tank with rolling tank
  #1
Member
 
naveen kumar s
Join Date: Aug 2016
Location: india, bengalore
Posts: 51
Rep Power: 10
navi is on a distinguished road
hello, I have simulated sloshing technique in fluid tank in cfx ansys 14, but my problem is i have used expression for angular velocity of using sinusoidal (expression name is "amp" and its image is in attachment), this expression i have put in domain motion , the rolling of tank is 6 degree but in expression is my equation (angle in radiens*omega in (rad/sec)*sin(omega*t)) is right , i have multiplied omega with roll angle in radians , just see my expression , can i multiply angle in radians to omega (which is frequency).
and below domain motion there is alternate rotation model what it does alternate motion , please give is there any other expression can give for fluid motion.
can i give motion in initiation, u,v,w is there
please help me
thank you




Last edited by navi; August 22, 2016 at 03:24. Reason: i guess image dind uploaded so typed an equation
navi is offline   Reply With Quote

Old   August 22, 2016, 06:49
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,830
Rep Power: 144
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
I do not understand your question. Can you state your question again?
ghorrocks is offline   Reply With Quote

Old   August 23, 2016, 00:35
Default
  #3
Member
 
naveen kumar s
Join Date: Aug 2016
Location: india, bengalore
Posts: 51
Rep Power: 10
navi is on a distinguished road
for tank motion i have to give expression and my tank motion is rolling in degrees , it is 6 degree ,
and i have given expression as
(6*(pi/180))*omega*sin(omega*t)

omega is in rad/sec

in above equation i have multiplied omega * (rolling angle in radians)
is my equation is right for tank simulation
i am giving this expression in outline tree
default domiain> basic setting > domain motion > rotating > angular velocity

in same dialog box, there is alternate rotation model, what this alternate rotation model does exactly
navi is offline   Reply With Quote

Old   August 23, 2016, 06:03
Default
  #4
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,830
Rep Power: 144
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
So you are using rotating frames of reference to model an oscillating rotation? Be aware that rotating frames of reference assumes constant domain velocity so the angular accelerations will not be accounted for. It is up to you to determine whether that is important or not.

If you model this using moving mesh it will include the full motion equations but the simulation will be considerably slower.
ghorrocks is offline   Reply With Quote

Old   August 23, 2016, 06:12
Default
  #5
Member
 
naveen kumar s
Join Date: Aug 2016
Location: india, bengalore
Posts: 51
Rep Power: 10
navi is on a distinguished road
how can i apply moving mesh for 3d tank, in tutorials there are only for 2d and when i try doing it by understanding 2d and applying same for 3d ,i need to give mass, moment of inertia , all this i how can i feed correctly
navi is offline   Reply With Quote

Old   August 23, 2016, 06:48
Default
  #6
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,830
Rep Power: 144
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
If you are using mass and moments of inertia then you are using the rigid body solver.

I think you need to go back to basics and make sure you are modelling the correct physics.

Is the motion known in advance or is it coupled to the the fluid motion?
Does the tank deform at all?
Please show an image of the tank motion.
ghorrocks is offline   Reply With Quote

Old   August 24, 2016, 00:54
Default
  #7
Member
 
naveen kumar s
Join Date: Aug 2016
Location: india, bengalore
Posts: 51
Rep Power: 10
navi is on a distinguished road
i have attached image, for this type simulation, i have alone gone through basics but its lil bit difficult so getting lot of doubt
Attached Images
File Type: jpg Capture.jpg (79.2 KB, 42 views)
File Type: jpg expresions.JPG (25.7 KB, 27 views)
navi is offline   Reply With Quote

Old   June 2, 2018, 00:51
Default sloshing and ship motion
  #8
New Member
 
Join Date: Nov 2016
Posts: 16
Rep Power: 9
kites is on a distinguished road
how to get result of sloshing pressure on tank walls
?
kites is offline   Reply With Quote

Old   June 2, 2018, 08:04
Default
  #9
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,830
Rep Power: 144
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
* Put a monitor point on the surface recording the pressure. Then you will get a time history of pressure at that point in Solver Manager.

* Integrate the pressure over the surface to get a force using the force function. Then put that CEL function in as a monitor point and you will have a time history in solver manager.

* You can also do this in post-processing for any time steps you saved transient results files for.
kites likes this.
__________________
Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.
ghorrocks is offline   Reply With Quote

Reply

Tags
expression, initiation, sinosoidal, sloshing, vof

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
Multiphase VOF wave tank quickly diverges long.1059 Fluent Multiphase 3 April 16, 2015 22:01
Draining of a Water Tank using VOF Pirate FLUENT 0 August 12, 2014 06:35
Overflow Error in Multiphase Modelling with Two Continuous Fluids ashtonJ CFX 6 August 11, 2014 14:32
sloshing in tank manoj kumar FLUENT 7 July 30, 2011 05:53
Terrible Mistake In Fluid Dynamics History Abhi Main CFD Forum 12 July 8, 2002 09:11


All times are GMT -4. The time now is 21:49.