CFD Standard Convergence Study

Hi

I'm investigating the vortex generation of a cat sailing boat for my masters Mech Eng project. I am using the cfd package 'cfx 5' and have been experimenting with various mesh configurations.

I am sure there must be standard ways of carrying out a convergence study in order to identify an optimum level of mesh refinement for my specifications. I have done plenty of this within FEA and assume that there must be some kind of similarities. Can anyone point me in the right direction? Are there any points within the cfx geometry model that I must be looking at in particular to make my results comparable to others?

I would greatly appreciate some advise and any useful links to web pages or journals.

Thanks for your time

Alec.

 

I assume you're looking at multi-phase flows. In which case, you need to have cells where you think the phase boundary should be, and anywhere you would expect to find flow that differs (significantly) from the flow at the far-field.

Other than that, it's pretty similar to a grid sensitivity study with FEA.

Cheers,

Tim B.

 

There is a lot of work going on to formalise verification and
validation of CFD predicitons in numerical ship hydrodynamics.
Fred Stern's paper in Gothenburg 2000 is a good start.

Also see the IIHR CFD pages at:
http://www.iihr.uiowa.edu/~shiphydro/Publications_reports.htm

Particularly:
Stern, F., Muste, M., Beninati, M.L., and Eichinger, W.E.,
“Summary of Experimental Uncertainty Assessment Methodology with
Example,” Iowa Institute of Hydraulic Research,
The University of Iowa, IIHR Report No. 406, July 1999, 37 pp.

Stern, F., Olivieri, A., Shao, J., Longo, J., and Ratcliffe, T.,
“Statistical Approach for Estimating Intervals of Certification
or Biases of Facilities or Measurement Systems Including
Uncertainties,” IIHR Report No. 442, December 2004, 67pp. (pdf)

Good Luck!
Leo.

 

try www.cfd-online.com
there are many guys who really get involved with this.
also there are some resources that you can reach.Cheers

 

Thankyou for the links I'll check them out. It's really the convergence study that I'm interested in. I think I may get some ideas from aero research papers too.

Alec