Learning Forum

[whiew]

Hi,

I am wondering whether setting the constant structural damping coefficient/ratio under Analysis Setting will override the Material Damping values (Alpha/beta) entered in Engineering Data.

In the application I have in mind, I want to assess the effects of material damping (values) on the overall steel structure (ropes supporting steel structure). So I have entered the alpha & beta values for the 2 rope materials in Engineering Data. When I set the Damping to be "on" in Analysis Settings, it shows Constant Structural Damping Coefficient, Stiffness Coefficient and Mass Coefficient (Attached screenshot). What should I enter here so that the material damping values are the primary drivers?

Note: Only the ropes have material damping values. No damping values have been set for steel (the rest of the model).

Any tips and advices would be great.

Cheers.

[peteroznewman]

Please use the Insert Image button to put the image into the post.   ANSYS staff are not permitted to open attachments.

Damping controls under Analysis Settings are added to the damping defined on the material in Engineering Data. 
I consulted the 2019 R2 training materials. The only time when no damping is applied is the undamped Modal analysis.
However, any analysis linked to that solution, such as Harmonic Response, will pick up damping from the material.
Link to a post where I put a summary table.

[peteroznewman]

I revised the post above.

The confusing thing about damping is different analyses support different types of damping.

As a general “rule”, damping ratio applies to MSUP analyses, damping coefficient (g) applies to Full analyses but they all support Rayleigh Alpha and Beta damping.