[beancurdsm]

hi,all
Recently i'm doing simulation on hydraturbine ,Fransis.And i want to know if numeca can fulfill this task?
thanks

[sanboju]

Hi,

Of course you can do simulations in CFView. You can create animate gifs. It only works for unsteady time configurations. When you start CFView to see the results of an unsteady time configuration job. Numeca ask you for the time steps you wanna see. click on "all time steps" for a full animation over 360º. To create a visualization you have to click on the record player (at the top right) and a menu will appear. Just only change Delay: 20, and Loops: 0.

In this case numeca create a *.jpg file every step you indicate you wanna a solution in Fine/turbo (computationi steering/control variables menu, on Save solution every: xxx) If you choose 1, and for example you choose for number of angular positions 180, numeca saves a output data every 2 degrees.

For the simulation, numeca will take pictures of the movement every 2 degrees of the rotor and it saves in the directory you choose (once you click on the menu I refer before). Once the simulation finish, numeca will create a simulation *.gif joining all the pictures. If you choose (from the recorder menu) delete image files, once the *.gif will be created, automatically numeca will delete the *.jpg files.

I hope I'll be helful.

Cheers.

[beancurdsm]

Thanks a lot,sanboju.
Maybe I should try unsteady configuration,for that option can really solve my task.But I have found CFview can also do simulation of steady,i mean points moving on stream lines of W velocity,and it can really animates flows in the turbine.

[sanboju]

Sure you can simulate a flow over a steady simulation and get the stream lines over your case, but I thought you wanna simulate the rotor in movement.

For steady simulation you will get in the job the same parameters (with less precission than unsteady) in a determinate time and with a fix angular position.

In this case, if you wanna get good results I recommend you to set in Fine/Turbo: Computation Steering --> Control variables --> Convergence criteria: -6.0

Greatings

[vlantrix]

Hi sanboju,

You seems to understand the principle of time step very well.. Actually I have some interrogations.

I want to simulate a CROR and therefore I want to save the outputs at different relative positions of the blades. Because I have 2X3 blades turning in opposite ways, my period is 60°.
Can you explain me what is represented by Number of angular position and Number of Time Steps?
Let's say that I want to register 6 positions in my period, what should I set as parameters? Thank you

[inarus]

Hello,

I've seen the infos provide in the user manual, though, Fine/Marine won't create a *,run file even for unsteady computation, like Fine/Turbo for example.

I have a marine propeller computed with ISIS-CFD (unsteady) and I can't see how I can animate it's rotation.

Any thoughts?

Thank you!

[KSP1]

--------------------------

[Rodrigo Correa]

Hello Inarus,

As described above you can save the scenes (pictures) of the Unsteady results and use a third-part software to generate your video. If you are not certain of how to generate the images, let me give you my personal preferable way to do so:
1. Reconstruct the unsteady data (when creating videos go for Surface Data).
2. Save/export the macro (python file) after you are happy with the scene. Bear in mind that it will record every movement you perform. As a result a bunch of "setcamera" will be present in that script.
3. Clean that file and let only the commands of interest to recreate the desired scene.
4. Loop over it and save your pictures.
5. use a third-party software to read the saved images and create the video

I will give you a small example here:

CFViewBackward(1210)
 
# set view
view_1 = [-1.0, 1.0, -1.0, 1.0, 'on']

 for i in range(start_step, end_step+1):
    """ add here the commands you end up after cleaning the macro/python file """

    view1 = ViewName()
    Limits(*view_1)
    .
    .
    .

    # set camera
    SetCamera(give the expected arguments)

    # saving picture
    Print(give the expected arguments)

It is always a good idea to generate the pictures in parallel (multiprocessing library will help you here).
I hope it helps you.

Rodrigo