I think Claudio Pedrazzi

Thanks,

Hamidreza Ahmadi Moghaddam Claudio Pedrazzi

For the ANSYS settings:

The full step time is 1s, the sub step is 0,001 s.

The boundary: I inserted a fixed support to the root of the blade and a rotational velocity for the body following the rotation direction clockwise.

.... The blade is assumed without aerodynamic effect as it was tested in a special chamber.

I used transient structural, and ploted directional deformation of a vertex at the Blade tip.

for the laser vibrometer those attached the parameters, I tried to put the reference same place as the vertex in simulation.

before I performed a modal analysis in both numerical and experiment and the error was less than 2%.

As I understand from Mr Claudio, do I need to reduce the full step time and the sub step?

It is a little bit confusing. I thought that you want to simulate the radial displacement while the blade is rotating.

Besides Claudio Pedrazzi

Thanks,

Hamidreza Ahmadi Moghaddam .... I understand what Claudio Pedrazzi

I attached the picture of my blade, I would be very glad to hear your guidlines to make it. I am still beginner with a lot to learn.

The blade will rotate on the Z axis, what I would like to measure is the vibration of the blade tip in the 3 directions.

Please follow the process that I described below for applying rotational velocity using joint load.

1. In Ansys mechanical since you have only one object then you (might) need to insert a connection that enables defining the joint. Right click on "Model" and from "Insert" select "Connections".

2. Right click "Connections" and from "Insert" select "Joint".

3. From "Details" pan select "Connection type" and set its value to "Body-Ground".

4. Select "Type" and set its value to "Revolute".

5.Select the "Scope" and then select the bottom surface of the blade (the one that is rotating about z axis).

6.If the Global coordinate system is already on the right spot then just use that one as your coordinate system in "Coordinate System" which is under "Reference" group. Otherwise, you need to create another coordinate system and consider the Z direction as rotation direction and then use this coordinate system as reference coordinate system.

7. Set values for "Torsional Stiffness" and "Torsional Damping" accordingly.

8. Change the "Behavior" from "Rigid" to "Deformable" if it make sense in your analysis.

9. Now select "Static Structural" from tree and from "Insert" select "Joint Load".

10. From "Details" pan change "joint" to the one you just created. Change the "Type" to "Rotational Velocity" and define the magnitude.

There you go!! Now you applied rotational velocity and will be able to measure (radial, etc.) displacement of your blade. The most important part of this process is that you define the coordinate system at the center of rotation and set the Z direction at axis of rotation.

Hope this answer helps.

I tried to follow your instructions, Inserte a joint as you can notice from the picture attached,

I had an error about MPC contact region, using the troubleshoooting on ANSYS guidlines I change the support and the behaviour from deformable to regid, yet I had the same error.

Now I returned to the basic solution trying to reduce the time step as per Mr Claudio suggest

When the blade rotates and is subject to certain impact. Its motion consists of three parts: rigid rotation; stable deformation; vibration around its stable deformation. If your numerical analysis does not model "sudden start" or "impact", then you do not find vibration (sinusoi....), but in your experiment, there is always "start" or "impact".