This question is for the turbo-machinery people:

I want to know what the state of the art is concerning turbine modelling in CFD. Not propeller, compressor or fan modelling where the mesh motion is prescribed and the fluid flow as a result of the prescribed mesh motion (rotating blades).

Has it been attempted or is it maybe commonplace to model turbines where the blade rotation is as a result of the fluid flowing through the impeller (Fluid structure interaction) I guess this is a very much more complex problem than modelling fans, compressors and propellers.

I will be glad to hear your opinions on this matter and for a few references if available.

Barry

Hello Barry,

The start of the art is EASM (Explicit Algebraic Stress Models) within a two-equation model formulation. It would be sometime before it can be used in a design environment. These models make the governing equations very stiff.

Thanks,

Thomas

Barry,

It sounds like you want to look at a freewheeling impeller (due to back flow through a line, or something similar, perhaps). This is a harder problem than dealing with a "normal" pump problem because the flow forces will produce a torque that has to be balanced against inertia and friction, etc. in the pump drive train. I solved a similar problem in a fairly simplified fashion in a previous life.

Depending on the level of detail that you need, there are a couple of ways to approach this kind of analysis. The best analysis could be performed by doing a 1-degree of freedom analysis, where the impeller in the model is allowed to spin based on a force balance calculated by the solver.

Regards, Alton

i want to get complete knowledge about CFD and its application on turbochemistry start from biegning give me detail and send email and attach books and massege

Hello Mukkarum,

Start with the following report by Bradshaw:

"Turbulence Modeling with application to turbomachinery" P. Bradshaw ME Department, Stanford University, CA 94305, U.S.A. Prog. Aerospace Sci. Vol. 32, pp. 575-624, 1996

If you cannot find this report, let know. I can snail mail the above report.

Thanks,

Thomas

please send me

""Turbulence Modeling with application to turbomachinery" P. Bradshaw ME Department, Stanford University, CA 94305, U.S.A. Prog. Aerospace Sci. Vol. 32, pp. 575-624, 1996 "

i will be very thank full

Hi,

Can you please send me the above mentioned report ? "Turbulence Modeling with application to turbomachinery" P. Bradshaw ME Department, Stanford University, CA 94305, U.S.A. Prog. Aerospace Sci. Vol. 32, pp. 575-624, 1996

I would greatly appreciate your help. Thanks in advance.

Regards,

Suman.

Dear Thomas,

I am very interested on that report (Turbulence modeling with application to turbomachinery) by P. Bradshaw. Could you please e-mail it to me too?!

dc@mail.vok.lth.se

Thank you very much ! Doru

Hello Mukkuram, Suman and Doru,

I will be glad to send you the reports. I do not have an electronic copy. I could mail you the reports by ordinary mail. So, please e-mail your mailing address at tabraha2@ford.com

Thanks,

Thomas

i am emailing u my mail address plz send me this report i will be very thank full

mukkarum

We recently modelled a turbo system with RADIOSS-CFD and asked ourselves the same kind of questions. I believe that if you use a coupled Fluid Structure code, you can easily model the inertial behavior of your turbine whose motion will be caused by the fluid flow. The remaining problem being the modeling of the reaction torque coming from the compressor chamber. Either you know a steady state torque and you can apply it on the axis of the turbine and the system will compute until it reaches an equilibrium, either you dont know and I'm afraid that you will have to model everything!

Dimitri

Thank you for your response. To tell you the truth I havn't given the reaction torque much thought!! But say the reaction torque in a known or may be calculated using simple physics, is the CFD for modelling such fluid structure interactions sorted out? I know that fans and compressors are frequently modelled using prescribed mesh motion, but what about fluid stucture interaction in turbine modelling.

In other words. Is it possible to model in 3D a free running turbo unit??

Thank you Barry

Barry,

Actually, there would be no specific problems doing it with RADIOSS-CFD (the code developed and marketed by my company). When we started this turbo project this is even the way we would have prefered to do it. By doing so you make sure that the air is the cause of the blades motion and that you will not end up simulating a kind of fan! We finaly gave an imposed rpm in order to be sure to compare similar things eventually with the actual code our client uses. If you are interested in you can e-mail me directly so we can discuss your case further into details.

Dimitri

Dimitri

It sounds very interesting. Do you have web page for the code where I may have a look??

Thank you very much for your input.

Barry

hello Thomas P. Abraham,

Have you send report on my mailing address

give me answer please

Hello Muukuram,

I will be mailing it this saturday. I got your mailing address.

Thanks,

Thomas

The web page is www.radioss.com

Dimitri

Hello Sir;

I want to know complete information about FLOW LAB PACKAGE.

It's price ; training cost and all other cost.

Waiting for prompt reply;

MUKKARUM HUSSAIN RESEARCH SCHOLER NED UNIVERSITY KARACHI PAKISTAN

Dear Sir, I am waiting for this report ,have u sent or not informe me Thanks