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[vivekek]

I am trying to estimate the engine C.G displacement using Harmonic analysis. The engine is modeled as a point mass and attached to the mounts through remote point. The mount contain a hyperelastic material, modeled as Yeoh 2nd order material. Since the material model is nonlinear and Harmonic analysis is linear, Is it possible to carry out a Harmonic analysis for such application.

[Aniket]

Docs mention that any material nonlinearity is ignored for harmonic analysis.
https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v221/en/wb_sim/ds_harmonic_analysis_type.html

For linear dynamic analyses, one needs to assume small deflections, so we only input viscoelastic material properties assuming linear elasticity (e.g., elastic modulus, Poisson's ratio). Think of it as looking at small vibrations of your elastomeric material.
If you need to consider hyperelasticity+viscoelasticity due to large strains, then the only option you have is to perform a transient analysis since only a transient analysis can consider nonlinear material effects, such as hyperelasticity.
-Aniket
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[vivekek]

Hi Ankit Thanks for your reply.
I only have the compression test data of the rubber material up to 25% strain. Since the uniaxial test data cant be used for the viscoelastic material model, I opted the hyper elastic material. Is there any method to model the viscoelastic material using the available test data?