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

unable to float the boat!!

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

Reply
 
LinkBack Thread Tools Display Modes
Old   January 10, 2012, 01:31
Unhappy unable to float the boat!!
  #1
Member
 
sanjay's Avatar
 
aerosapien
Join Date: Sep 2010
Posts: 59
Rep Power: 6
sanjay is on a distinguished road
I am working on tunnel hull speed boat. The wave generated is making the body submerged even with less amplitude of wave. Please help me resolve the problem!!!!
Attached Images
File Type: jpg side.jpg (32.3 KB, 35 views)
File Type: jpg top.jpg (41.9 KB, 35 views)
sanjay is offline   Reply With Quote

Old   January 10, 2012, 03:30
Default
  #2
Senior Member
 
Ping
Join Date: Mar 2009
Posts: 223
Rep Power: 8
ping is on a distinguished road
ensure your boat flows in still water first in still water - weight could be incorrect.
ping is offline   Reply With Quote

Old   January 10, 2012, 04:24
Default
  #3
Member
 
sanjay's Avatar
 
aerosapien
Join Date: Sep 2010
Posts: 59
Rep Power: 6
sanjay is on a distinguished road
it doesn't folat it appears submerged. Should I change the position of ship ? serious help required!!!
Attached Images
File Type: jpg side.jpg (12.8 KB, 22 views)
sanjay is offline   Reply With Quote

Old   January 10, 2012, 04:51
Default
  #4
Senior Member
 
Ping
Join Date: Mar 2009
Posts: 223
Rep Power: 8
ping is on a distinguished road
as I said you need to run with zero in/out flow the case for a few seconds (eg using a timestep of about 0.05s) and monitor vertical motion (sink). if there is no movement then the gravity forces are balanced by the bouyancy forces. if the hull is in a submerged condition after this run, then your hull mass is too high for this hull shape - simple hydrostatics. do the boat tutorial in the Help if this does not understood. ensure you have freed the required DOFs!
ping is offline   Reply With Quote

Old   January 10, 2012, 23:01
Default
  #5
Member
 
sanjay's Avatar
 
aerosapien
Join Date: Sep 2010
Posts: 59
Rep Power: 6
sanjay is on a distinguished road
I found the solution myself. Actually its got nothing to do with buoyancy. Just go to VOF wave >> head wave >> adjust the point on water level, its simple as that. Thanks for the sharing your opinion. Some more questions to come

http://aerosapien.blogspot.com/
sanjay is offline   Reply With Quote

Old   January 11, 2012, 00:54
Default
  #6
Senior Member
 
Ping
Join Date: Mar 2009
Posts: 223
Rep Power: 8
ping is on a distinguished road
well if you had followed my instructions, the boat would rise to the surface of where your flat wave had been incorrectly set, so it is in fact about bouyancy!
ping is offline   Reply With Quote

Old   January 11, 2012, 22:54
Default
  #7
Member
 
sanjay's Avatar
 
aerosapien
Join Date: Sep 2010
Posts: 59
Rep Power: 6
sanjay is on a distinguished road
I do agree about buoyancy. What u said is right.

regards
http://aerosapien.blogspot.com/
sanjay is offline   Reply With Quote

Reply

Thread Tools
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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
OpenFOAM and gpgpu dewald OpenFOAM 37 August 29, 2014 09:32
openfoam 1.6 on debian etch romant OpenFOAM Installation 9 May 6, 2010 02:26
Need help with the error cfdproject OpenFOAM Other Meshers: ICEM, Star, Ansys, Pointwise, GridPro, Ansa, ... 0 April 14, 2009 15:45
Missing math.h header Travis FLUENT 4 January 15, 2009 11:48
to correct me an udf program farida hamadi FLUENT 0 December 18, 2004 05:54


All times are GMT -4. The time now is 13:14.