Separation of Flow problems

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

 March 16, 2006, 13:10 Separation of Flow problems #1 Simon c Guest   Posts: n/a Hello all, an aerofoil iam looking into is showing some odd results, namely the flow is far to attached to the aerofoil where the flow has slowed. From experience and using xfoil i should expect to see a seperation of the flow. is there any way of forcing fluent to stop being so generous in attaching the flow. Any ideas would be welcome, iam using standard K-e model with Y+ values all between 30-70 and with a very low speed of 15m/s. Yours S

 March 16, 2006, 15:01 Re: Separation of Flow problems #2 MOHAMMED Guest   Posts: n/a try to increase the velocity to 80 m/s and the angle of attack and see what will happen

 March 16, 2006, 16:16 Re: Separation of Flow problems #3 Razvan Guest   Posts: n/a The answer to your problem is very simple: switch standard k-e with SST-kw. The underprediction of separated flows is a well known problem of standard k-e turbulence model. Another advice would be to use a y+=1 mesh instead, the results will surely improve. Razvan

 March 19, 2006, 13:05 Re: Separation of Flow problems #4 Simon c Guest   Posts: n/a Thanks for the replys. Should have mentioned thats its a car aerofoil so that pressure drag dominates even at 0 angle of attack. Changed the value of length scale within the inlet boundary condition and iam now seeing what i expected. I thought orginally that I should insert a value of L= to my aerofoil length, but using a smaller value I get results I expected. Why is this?? I will have a go with the other turbulence model but my results are good enough now to prove my evaluation of how poor this aerofoil is! Thanks again Yours Simon

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post ivan_cozza OpenFOAM Running, Solving & CFD 2 May 26, 2010 10:08 TWaung CFX 2 March 29, 2009 18:42 Daniel FLUENT 0 January 26, 2009 00:54 ram Main CFD Forum 5 June 17, 2000 21:31 Francisco Saldarriaga Main CFD Forum 1 August 2, 1999 23:18

All times are GMT -4. The time now is 21:58.