Forced Transition, how to?

hxaxtma · April 12, 2016, 13:28

Hi guys,

lets say I am simulating a 2D airfoil and I do exactly know the point of transition due to a trip on the airfoil's surface.

Since I do not want to use a transition model I was thinking about splitting my surface in laminar and turbulent region an setting the turblence parameters in the laminar region to 0. Do you think this will work out?

Any experience?

ashishmagar600 · September 24, 2017, 17:18

Hello there.

I have been trying the same thing since past few weeks. But no success. There is a problem with compilation.

There are some publications which show to modify komegasst and SA models for laminar and turbulent cellzones.

if anyone wants, post in here, I will upload it.

sheaker · September 24, 2017, 17:46

Hello hxaxtma and ashishmagar600.
Could some of You possibly help me running of 2d airfoil case with simpleFoam? I would like to calculate aerodynamic coefficients and separation point and compare it with experimental data. I have successfully run case with laminar turbulence model and with SpartAllmaras turbulence model. I cannot succeed with k-epsilon and k-omega SST turbulence models. It looks like both of You are experienced users. Maybe You could help me and take a look on my case if possible.
Have a nice day.
Sheaker

April 12, 2016, 13:28	Forced Transition, how to?	#1
hxaxtma Senior Member Join Date: Jan 2014 Posts: 179 Rep Power: 12	Hi guys, lets say I am simulating a 2D airfoil and I do exactly know the point of transition due to a trip on the airfoil's surface. Since I do not want to use a transition model I was thinking about splitting my surface in laminar and turbulent region an setting the turblence parameters in the laminar region to 0. Do you think this will work out? Any experience?

September 24, 2017, 17:46		#3
sheaker Senior Member Oskar Join Date: Nov 2015 Location: Poland Posts: 184 Rep Power: 11	Hello hxaxtma and ashishmagar600. Could some of You possibly help me running of 2d airfoil case with simpleFoam? I would like to calculate aerodynamic coefficients and separation point and compare it with experimental data. I have successfully run case with laminar turbulence model and with SpartAllmaras turbulence model. I cannot succeed with k-epsilon and k-omega SST turbulence models. It looks like both of You are experienced users. Maybe You could help me and take a look on my case if possible. Have a nice day. Sheaker __________________ How to set two stroke engine with scavenging? Salome, sliding interface and "Zero length edge detected."

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September 24, 2017, 17:18		#2
ashishmagar600 Member Ashish Magar Join Date: Jul 2016 Location: Mumbai, India Posts: 81 Rep Power: 10	Hello there. I have been trying the same thing since past few weeks. But no success. There is a problem with compilation. There are some publications which show to modify komegasst and SA models for laminar and turbulent cellzones. if anyone wants, post in here, I will upload it.