PARAM, ALPHA1

Bulk Data Entry Adds Rayleigh damping to viscous damping for structural mesh.

Parameter Values Description
ALPHA1 <Real>

Default = 0.0

 PARAM, ALPHA1 is used in frequency response, transient response, modal complex eigenvalue, and nonlinear explicit analyses. This parameter is also supported for JOINTG with JTYPE=SLIPRING in explicit analysis.

If PARAM, ALPHA1 and/or PARAM, ALPHA2 are not equal to zero, then Rayleigh damping is added to the viscous damping. ALPHA1 is the scale factor applied to the mass matrix and ALPHA2 to the structural stiffness matrix as in:

[ B ' ] = [ B ] + A L P H A 1 ⋅ [ M ] + A L P H A 2 ⋅ [ K ] MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aadaWadaqaaiaadkeacaGGNaaacaGLBbGaayzxaaGaeyypa0ZaamWa aeaacaWGcbaacaGLBbGaayzxaaGaey4kaSIaamyqaiaadYeacaWGqb GaamisaiaadgeacaaIXaGaeyyXIC9aamWaaeaacaWGnbaacaGLBbGa ayzxaaGaey4kaSIaamyqaiaadYeacaWGqbGaamisaiaadgeacaaIYa GaeyyXIC9aamWaaeaacaWGlbaacaGLBbGaayzxaaaaaa@554D@