CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > Siemens > STAR-CCM+

Propeller nominal wake: KVLCC2

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

LinkBack Thread Tools Display Modes
Old   November 27, 2017, 14:50
Default Propeller nominal wake: KVLCC2
Soroush Kargar
Join Date: Apr 2017
Posts: 31
Rep Power: 3
Seervan is on a distinguished road
Hi all
I am trying to asses nominal wake fraction of a ship model: KVLCC2
I have determined the velocity contours at propeller disc. So my question is how to determine nominal wake fraction, w ?
The relation is w=1-Va/U which U is the ship or flow velocity.
My guess is that I extract the x-velocity values at propeller disc which are the Va values at every cell, then extract them as a XYZ table as .csv, then use the above formula to asses w at every cell, then take an average on them. Is this approach correct? Any ideas?
Seervan is offline   Reply With Quote

Old   December 6, 2017, 11:58
New Member
Dong Seo
Join Date: Aug 2010
Posts: 4
Rep Power: 10
wester is on a distinguished road
After extracting the velocity components, you need to do some post-processing. Please have a look at the following document. There is a description about the post-processing.
wester is offline   Reply With Quote

Old   December 10, 2017, 11:44
Soroush Kargar
Join Date: Apr 2017
Posts: 31
Rep Power: 3
Seervan is on a distinguished road
Thanks for the answer

By the way I also found a simple approach that can be useful and it satisfies the ITTC conditions. after forming the propeller disc and converged results, you can define a field function defining the wake. Then create an Surface Average Report within the pertaining node on the related disc. The Surface Average complies the wake integral formula suggested in the references such as "Marine propellers and propulsion" by Carlton, pp.67. Thus you don't need to tabulate the data on the disc and post process them in the hard way.
I validated the data with the MOERI experiment and there is good agreement.

Seervan is offline   Reply With Quote


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
Propeller calculation toil CFX 15 May 22, 2017 04:06
having problems with implementing the wake rollup for a panel method smilesgiles89 Main CFD Forum 0 August 6, 2015 20:09
wake behind propeller samy_20042004 CFX 1 November 29, 2012 16:17
Modelling a propeller tomg STAR-CCM+ 4 April 28, 2011 17:22
propeller in non-uniform flow ubik Main CFD Forum 0 February 20, 2007 06:28

All times are GMT -4. The time now is 23:41.