How to model a (gas-turbine) swirler in 2D

Giuki · May 6, 2009, 10:55

Dear all,

I'm trying to simulate a RQL type of combustion chamber. However to achieve a physical flow pattern I should include a swirler at the entry. I read through different parts of the User's Guide but couldn't find a solution. As I understand it is possible in a 3D model but cannot find any information for 2D. Is it even possible in 2D to have a (sort of) swirling flow?

I'm using preheated air (800K) as oxidizer and methane (300K) as fuel. The combustion model I use is the non-premixed model with pdf-table. As turbulence model I use the RNG k-eps model.

Thanks in advance!

Giuki

AdidaKK · June 11, 2009, 21:04

im gona paste here some question and response frome ANSYS FAQ.

Is there any way of doing a 2D simulation in CFX?

Yes. From a 2D mesh of the geometry, extrude it one element in the normal direction. For a 2D planar simulation this would be one element in the normal vector direction, for a 2D axisymmetric simulation this would be sweeping a small angle with one element. For the planar mesh the extrusion should be approximately equal to the smallest element edge length in the model, for the axisymmetric mesh the sweep should be a small angle, maximum 5° but smaller if you want high accuracy.
In CFX-Pre you should set the top and bottom faces of the extrusion as symmetry planes. If you want to include swirl in the model use periodic boundaries. The remaining boundaries should be set as walls, inlets, openings and outlets to define the flow.
The CFX documentation discusses 2D simulations and it is recommended you read it before proceeding.

but..you'r working in FLUENT i "suppose" that the way of works its very similar.

another thing im working in a combustion chamber too from a HITACHI GE turbine,and i have some problems to do design the chamber in CAD,it is possible if you can share with me your cad design of the combustion chamber?

regards

Giuki · June 12, 2009, 05:21

Dear AdidaKK,

Thanks for the advice, this is an interesting way of doing a 2D simulation, I will get into it.

Are you interested in a 2D model or a 3D model?

Regards,

Giuki

AdidaKK · June 12, 2009, 05:39

im interesting in the 3d model

my mail its adidakk@gmail.com

thanks allot =)

best regards

Giuki · June 12, 2009, 08:19

Dear AdidaKK,

Well I only have a 3D model for an adjusted geometry, which is a configuration for a flameless combustion regime, I don't know if that would help you?

PS. The model is build in SolidWorks 2008, I don't know if you can use this format...

Regards,

Giuki

AdidaKK · June 12, 2009, 16:51

Giuki

im working actually with solidworks 2008 sp3,im really new in this CAD,but i love it XD.all the tutorials are very cool.

and respect of the combustion chamber CAD ,its just for have an idea of the problem design .My real problem its i dont have the design planes of the tubular chamber,(Hitachi Turbine GE 25M), just have the real unit in the lab of my University,so i have to work on it.

so if you can share your cad that be wonderfull ,just for have an idea.

best regrads
AdidaKK

May 6, 2009, 10:55	How to model a (gas-turbine) swirler in 2D	#1
Giuki New Member Giuki Cael Join Date: May 2009 Location: Belgium/The Netherlands Posts: 13 Rep Power: 17	Dear all, I'm trying to simulate a RQL type of combustion chamber. However to achieve a physical flow pattern I should include a swirler at the entry. I read through different parts of the User's Guide but couldn't find a solution. As I understand it is possible in a 3D model but cannot find any information for 2D. Is it even possible in 2D to have a (sort of) swirling flow? I'm using preheated air (800K) as oxidizer and methane (300K) as fuel. The combustion model I use is the non-premixed model with pdf-table. As turbulence model I use the RNG k-eps model. Thanks in advance! Giuki

June 11, 2009, 21:04		#2
AdidaKK Member Mauricio Caamaño Flores Join Date: May 2009 Location: Punta Arenas, Chile Posts: 62 Rep Power: 17	im gona paste here some question and response frome ANSYS FAQ. Is there any way of doing a 2D simulation in CFX? Yes. From a 2D mesh of the geometry, extrude it one element in the normal direction. For a 2D planar simulation this would be one element in the normal vector direction, for a 2D axisymmetric simulation this would be sweeping a small angle with one element. For the planar mesh the extrusion should be approximately equal to the smallest element edge length in the model, for the axisymmetric mesh the sweep should be a small angle, maximum 5° but smaller if you want high accuracy. In CFX-Pre you should set the top and bottom faces of the extrusion as symmetry planes. If you want to include swirl in the model use periodic boundaries. The remaining boundaries should be set as walls, inlets, openings and outlets to define the flow. The CFX documentation discusses 2D simulations and it is recommended you read it before proceeding. but..you'r working in FLUENT i "suppose" that the way of works its very similar. another thing im working in a combustion chamber too from a HITACHI GE turbine,and i have some problems to do design the chamber in CAD,it is possible if you can share with me your cad design of the combustion chamber? regards Last edited by AdidaKK; June 12, 2009 at 05:43.

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June 12, 2009, 05:21		#3
Giuki New Member Giuki Cael Join Date: May 2009 Location: Belgium/The Netherlands Posts: 13 Rep Power: 17	Dear AdidaKK, Thanks for the advice, this is an interesting way of doing a 2D simulation, I will get into it. Are you interested in a 2D model or a 3D model? Regards, Giuki

June 12, 2009, 05:39		#4
AdidaKK Member Mauricio Caamaño Flores Join Date: May 2009 Location: Punta Arenas, Chile Posts: 62 Rep Power: 17	im interesting in the 3d model my mail its adidakk@gmail.com thanks allot =) best regards

June 12, 2009, 08:19		#5
Giuki New Member Giuki Cael Join Date: May 2009 Location: Belgium/The Netherlands Posts: 13 Rep Power: 17	Dear AdidaKK, Well I only have a 3D model for an adjusted geometry, which is a configuration for a flameless combustion regime, I don't know if that would help you? PS. The model is build in SolidWorks 2008, I don't know if you can use this format... Regards, Giuki

June 12, 2009, 16:51		#6
AdidaKK Member Mauricio Caamaño Flores Join Date: May 2009 Location: Punta Arenas, Chile Posts: 62 Rep Power: 17	Giuki im working actually with solidworks 2008 sp3,im really new in this CAD,but i love it XD.all the tutorials are very cool. and respect of the combustion chamber CAD ,its just for have an idea of the problem design .My real problem its i dont have the design planes of the tubular chamber,(Hitachi Turbine GE 25M), just have the real unit in the lab of my University,so i have to work on it. so if you can share your cad that be wonderfull ,just for have an idea. best regrads AdidaKK