[andrea.mariotti]

Hi, I'm new in this community and also in using fluent.
I have a simple question before start my thesis at the university: is it possible to use fluent in order to simulate the action of the water on the blades of a simple turbine? I mean, is it possible to simulate the rotation of the impeller without forcing a rotational speed? The final goal is to study different blade configurations.
Thank you so much!

[cactilio86]

absolutely yes

[blackmask]

If you know the momentum inertia and mechanical property of the turbine, of course it is possible. It then becomes an easy question of building the relationship between the rotation speed and the force/moment of the turbine.

[andrea.mariotti]

Thank you so much!
I'll try doing this simulation. Do you know if there is a tutorial explaining movements and so on?

[Jim87]

movement are mentiont in a lot of tutorials. But the 13. Tutorial (Mixing plane model) might fit to your affords.

If you have the possibility to enter the customer portal you might find some cases for fan / turbine / turbo-machine. Contacting your local fluent distrubution might also helb, they know all tutorials and usually can help newbees with information material and examples.

[andrea.mariotti]

Thanks, I'll try this tutorial!!

[andrea.mariotti]

Hi, I was able to do a simulation of a simple turbine in a cylindric enclosure with set and fluid angular velocity. Now I will measure the power that the fluid transmits to the turbine, can you help me? How can I do? Thank you so much!

[andrea.mariotti]

I was able to do some simulations of simple turbines in a cylindric enclosure with setted fluid and angular velocity of the turbine. Now I will measure the power that the fluid transmits to the turbine, can you help me? How can I do? Thank you so much!

[Jim87]

easiest way might be to plot the needed physical values of your turbine area.

Such as pressure, velocity....

An davanced option could be using UDS etc.

[andrea.mariotti]

So you advise me to plot the pressure that works on the blades of the turbine and in this way calculate the forces?
Do you know if exists a easier way? For example I found in " Results -> Reports " a function called " forces " and it that " moments " , is it ok for me?
Thank you so much!!

[Jim87]

I was never interested in Power or Forces, but one possibility should be

Report -> Result Reports - Forces -> Momentum (maybe Try)

There is a tutorial Rotating Machinery Modeling in ANSYS Fluent 14.5, maybe take a look if there are informations.

your question isn't that exotic: http://www.cfd-online.com/Forums/flu...d-turbine.html

http://www.cfd-online.com/Forums/flu...-analysis.html

http://www.cfd-online.com/Forums/flu...-analysis.html

good luck

[andrea.mariotti]

I really appreciate your help!! Thank you!
Bye

[andrea.mariotti]

Hi Stephan, last thing: do you know the way that I can make my turbine free to move without assigning a rotational speed?
Thank you again!

[Jim87]

Free to move means a rotation of the turbine?

- First thing that comes in my mind is working with dynamik meshes. Maybe you can use them to generate a rotation structure for your mesh.

- In an old project I moddelt a projectile moving through a melt. In order to keep the model easy I used "kinematic reversal" (hope this is a well english translation). Instead of the movement of the projectile and its mesh. I fixed the geometry and translatet all the movement to the fluid (easier to solve).

Maybe you can asume this as an option.

- I'm not that fit in building dynamic meshes and models but these gentlemen helped me in the past: Jonathan, blackmask.

Maybe send them a message, hope that they are more practised in these questions.

Or search in the threads, turbines seems to be the main reason to use fluent (for the forst time).

http://www.cfd-online.com/Forums/flu...blade-mrf.html
http://www.cfd-online.com/Forums/flu...ng-blades.html

good luck