Ansys 12.1 material damping through GUI

[DaveChch]

Hi,

I’m trying to create a model to conduct transient analysis of a torsion pendulum that I’m designing. The system is an inertia connected to a torsion bar that consists of 2 components; a cylindrical wooden specimen surrounded by a thin walled metallic tube. I want to be able to input the material damping properties (loss coefficients) of both the wood and the metal separately, but am struggling to do so. Is there a way that I can do this through the GUI (ANSYS 12.1) without having to delve into code? (I’m not very confident with that).

Additional info:
The whole idea of the pendulum is to measure damping (via free decay) of a wood sample. The sample is surrounded by the chamber to minimise moisture loss, so the chamber is also being stressed in torsion. I have created a simple Matlab model treating the system as an inertia connected to a rigid wall through two springs and two dampers (all in parallel), and would really like an ansys model to validate this and allow me to play around with geometry etc before I start to build it. Thus far I have used a transient structural analysis and modal analysis in ANSYS 12.1. I’ve used ANSYS a bit before, but never for transient analysis, so this is a bit new to me.

Thanks in advance.
Dave

 

[kan123]

The DMPRAT command is used to apply constant damping across a model. You can specify damping for separate materials as a material property with MP,DMPR,value. However, this can only be used for harmonic analyses and not a transient or spectrum analysis. This is explained in the Help for the DMPRAT command.