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Tipakorn February 19, 2006 21:39

How to set moving mesh in this case?
My case study like is water turbine. We input water's velocity and impact blade that we want to know rpm of blade. But I don't know how to set moving mesh. Please help me. It's important. I want to know quickly Thank you

Fred Kaspersky February 20, 2006 02:33

Re: How to set moving mesh in this case?
I suppose you need to use Rotating Deference Frames. For extra informations You can read:

Anton Lyaskin February 20, 2006 02:42

Re: How to set moving mesh in this case?
There are two ways to do this.

The first one doesn't need moving mesh at all - you can just run you case with implicit rotating reference frame with different RPMs, then look at the torque vs RPM curve and choose the point which corresponds to your value of torque, produced by generator or what else is coupled with your turbine (you'll need also torque vs RPM curve for this device, so the intersection of these two curves will give you the point).

The secong way is much more complicated, because you'll have not only to set moving mesh itself (see tutorial 7), but to write a user subrouting for integration of a simple ODE for rotation. So you better think twice, which way to choose!

Tipakorn February 20, 2006 22:45

Re: How to set moving mesh in this case?
Um, Thanks. But I need to know about command step by step becase I don't have tutorial the same like this and I don't have much time to learn by myself. Thamks

Kevin February 21, 2006 02:27

Re: How to set moving mesh in this case?
It sounds like you need to perform an indeterminate mesh motion analysis, where the position/rpm of the turbine is not known beforehand. There are no default tutorials provided with STAR-CD showing how to do this but I did write a simple example a long time ago for linear motion showing how a static valve could be moved based on the force of the fluid acting on it. Please work through your local STAR-CD agent and have them contact Kevin Jones in the CD-adapco Seattle office in order for you to receive a copy of this example. Note it will be provided as is with no support included. You will also need to be very familiar with EVENTS in pro-STAR and comfortable with programming user subroutines in FORTRAN in order to be successful at what you want to do.

Tipakorn February 21, 2006 22:11

Re: How to set moving mesh in this case?
Thank you, Kevin. But local agent in Thailand isn't direct in the CD-adapco. He bring it from Singapore. Can I contact Kevin Jones directly? Or what should I do? Thank you

droper March 17, 2006 02:44

How to set moving mesh?
i have to study the air flow around a moving wall. I don't know how to set the moving grid. Please help me as soon as possible.

Abdulaziz Rajab April 27, 2006 13:19

Re: How to set moving mesh?

I do not know which package you are using

However, most FE pakages containg ALE formulation Algorithm

If you are using ANSYS you can input this in /prep7 commands


Yours abdulaziz

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