PARAM, COUPMASS & WTMASS

Karthic_22061

Hi,

In case of Direct Frequency Response Analysis

Wat is the differnce between the lumped mass matrix approach and coupled mass matrix (PARAM, COUPMASS)

Also please tell what they actually mean practically ?

WTMASS (Weight-To-MASS parameter, multiplier for the terms of the structural mass)
what is the purpose of using this card and its physical significance

 

Altair Forum User

Hi Karthic,

In the lumped mass option, the distributed mass of an element is simply divided up and the parts are located at the connected grid points. In the coupled mass option, the distributed mass is replaced by a nondiagonal mass matrix which couples the connected grid points. The latter method is sometimes more accurate, but it uses more computer time.

Param WTMASS converts weight to mass density.