Volute outlet flow into impeller inlet

Anthony_impeller · December 14, 2010, 19:33

Hello all,

Firstly this forum is an excellent resource and all that contribute should be recognised as generous and extremely helpful.

I am investigating basic fluid flow through a two stage turbine model. I have modelled up both a nozzle and volute to direct flow radially towards an outlet. (Picture 1)

I am having trouble modelling an impeller at this outlet. I would like to either include the impeller in a single CFX simulation or feed the volute outlet data to a seperate CFX simulation.

When adding the impeller mesh to the CFXpre software I recieve a single passage mesh. (Picture 2)

I would like to have the entire velocity (pressure and such) distribution of the volute acting on the impeller blades. How can I simulate this?

I am not sure whether to operate CFXpre in turbo mode or general mode and what boundaries (and connections) to establish.

Any help or references to specific resources would be very much appreciated. If more information or files are required to answer please let me know and I will upload them with haste.

Kind Regards,
Anthony.

BalanceChen · December 30, 2010, 08:34

I haven't done the turbine computation, but i recently am doing some simular computation on a compressor. Do you use the Pre Turbo mode? In this mode, you can specify the passages you want to model. For the volute, just use the stator component when import the mesh, no "blade" or "hub" need to be set, the default boudary should be wall, so it should have no problem in the simulation.

Hope it helps,

Best wishes,

BalanceChen

nitheshkumble · December 13, 2011, 02:32

hi,

I am investigating basic fluid flow through radial turbine model. I have modelled up both a stator and volute to direct flow radially towards an outlet.
I would like to simulate volute casing and rotor simulation interaction using CFx.

1. firstly,I want simulate only volute casing ,for that how to give BC,interface in CFX.
2.ansys mesh is used for meshing.
3.in cfx pre ,while importing whether it is necessary that we have to import only in .gtm or .cfx format.

with regards,
Nithesh KG

nitheshkumble · December 13, 2011, 02:45

only one sector was meshed ,hence you will get only that sector in the CFX pre.

To get entire blade meshing and simulation you have to follow the following method,
right click on mesh in CFX pre (tree),you will get mesh transformation, give angle for transformation. (for an example suppose rotor blade is 15 then 360/15=24 degree).

ghorrocks · December 13, 2011, 16:17

Anthony,

Have you looked at the various stage interface options such as frozen rotor? Look these up in the documentation and have a look at the tutorials on rotating machinery.

December 13, 2011, 02:32	how to simulate volute -rotor for radial turbine	#3
nitheshkumble New Member Join Date: Feb 2011 Posts: 13 Rep Power: 15	hi, I am investigating basic fluid flow through radial turbine model. I have modelled up both a stator and volute to direct flow radially towards an outlet. I would like to simulate volute casing and rotor simulation interaction using CFx. 1. firstly,I want simulate only volute casing ,for that how to give BC,interface in CFX. 2.ansys mesh is used for meshing. 3.in cfx pre ,while importing whether it is necessary that we have to import only in .gtm or .cfx format. with regards, Nithesh KG

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December 30, 2010, 08:34		#2
BalanceChen Member Join Date: Sep 2010 Posts: 45 Rep Power: 15	I haven't done the turbine computation, but i recently am doing some simular computation on a compressor. Do you use the Pre Turbo mode? In this mode, you can specify the passages you want to model. For the volute, just use the stator component when import the mesh, no "blade" or "hub" need to be set, the default boudary should be wall, so it should have no problem in the simulation. Hope it helps, Best wishes, BalanceChen

December 13, 2011, 02:45		#4
nitheshkumble New Member Join Date: Feb 2011 Posts: 13 Rep Power: 15	only one sector was meshed ,hence you will get only that sector in the CFX pre. To get entire blade meshing and simulation you have to follow the following method, right click on mesh in CFX pre (tree),you will get mesh transformation, give angle for transformation. (for an example suppose rotor blade is 15 then 360/15=24 degree).

December 13, 2011, 16:17		#5
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	Anthony, Have you looked at the various stage interface options such as frozen rotor? Look these up in the documentation and have a look at the tutorials on rotating machinery.