AleTre
Mechanical
- Oct 14, 2013
- 3
Hello!
I am modelling a sandwich in both Nastran and Samcef in order to compute the harmonic response. I am encountering some issues in damping modelling.
The core of my sandwich is a polymer with a constant loss factor. While I can easily model it in Nastran by defintion of GE in the MAT Bulk Data entry, I cannot use the same value in Samcef since material dissipation is modelled as viscous damping through the VELA parameter (at least this is what I got from the User's guide).
I tried to define a harmonic material in Samcef (shear modulus and loss factor are defined as a function of frequency) and to use SDAMPING in Nastran but I think I am making a mistake in the SDAMPING tables definition. I do not have much experience with SDAMPING so any hint on its use would be much appreciated.
Does anyone know any other method to overcome this issue?
Thanks in advance!
Cheers,
Alex
I am modelling a sandwich in both Nastran and Samcef in order to compute the harmonic response. I am encountering some issues in damping modelling.
The core of my sandwich is a polymer with a constant loss factor. While I can easily model it in Nastran by defintion of GE in the MAT Bulk Data entry, I cannot use the same value in Samcef since material dissipation is modelled as viscous damping through the VELA parameter (at least this is what I got from the User's guide).
I tried to define a harmonic material in Samcef (shear modulus and loss factor are defined as a function of frequency) and to use SDAMPING in Nastran but I think I am making a mistake in the SDAMPING tables definition. I do not have much experience with SDAMPING so any hint on its use would be much appreciated.
Does anyone know any other method to overcome this issue?
Thanks in advance!
Cheers,
Alex
