How to check in-plane rotational velocity
 

Greetings all. I am trying to simulate a nozzle spinning about its axis. I want to check the in-plane rotational velocity vectors to verify the wall rotations in ANSYS post processing. What I am getting are the vectors perpendicular to the plane but I want to check the in-plane velocity vectors to see the rotation. Can some one please guide me in this regard? I will be very thankful. Cheers ;)

Attachment 89465

I am kind of confused as to what you are wanting to do. The rotational speed of your domain is stored/calculated in CFX-Post as a CEL variable named "Angular Velocity".

aero_head, appreciate it but actually I am simulating in ANSYS Fluent dear

Hello Syed,

My mistake, I wasn’t sure which program you were using.

I found this: https://www.researchgate.net/file.Po...01479739664413

When you solve a problem in a rotating reference frame, you can plot or report both absolute and relative velocities. For all velocity parameters (e.g., Velocity Magnitude and Mach Number), corresponding relative values will be available for postprocessing (e.g., Relative Velocity Magnitude and Relative Mach Number). These variables are contained in the Velocity... category of the variable selection drop-down list that appears in postprocessing panels. Relative values are also available for postprocessing of total pressure, total temperature, and any other parameters that include a dynamic contribution dependent on the reference frame (e.g., Relative Total Pressure, Relative Total Temperature).

Modeling Flows in Moving Zones
When plotting velocity vectors, you can choose to plot vectors in the absolute frame (the default), or you can select Relative Velocity in the Vectors Of drop-down list in the Vectors panel to plot vectors in the rotating frame. If you plot relative velocity vectors, you might want to colour the vectors by relative velocity magnitude (by choosing Relative Velocity Magnitude in the Color By list); by default they will be colored by absolute velocity magnitude.

Define a custom vector field which is the velocity but projected onto the plane. If the plane is the yz-plane, this can be as simple as just setting the x-velocity component to 0 and keeping the y-velocity and z-velocity. For the general case of an arbitrary surface, you would take the vector projection of the velocity vector onto the area vectors.


And then plot this new custom vector field.

Got it. Thanks Mate

Lucky can you please guide me a little on how can I define this new custom vector field? I am a bit new to fluent. Thanks in advance ;)

Are you using Fluent or CFD post?

In Fluent there's even easier ways to display vectors.

That's great. Please tell me the procedure for Fluent. Thanks in advance. ;)

Hi Syed,

Just click on the link that says display vectors in LuckyTran’s message.

Thanks a ton aero_head. Stay blessed.

Hi ANnagant. Thanks for your reply. But I am using ANSYS Fluent in my case and I am unable to locate the option for angular velocity. I will be very thankful I you can guide me about this option for FLUENT. Thanks

Click the linky....there's step by step guides in the manual


Or search Displaying Vectors in your user's guide.

Thanks a ton Lucky. Found it eventually. Stay Blessed <3