This paper presents a different approach to the high-frequency residual terms from the standard formulations used. The basic idea behind it is to calculate the high-frequency residual terms using only the local modal parameters (i.e. the mode-shape information) instead of using all modal parameters (i.e. natural frequencies and damping factors as well). When this is done, the high-frequency residual matrix becomes related to the mass matrix instead of to the stiffness matrix. This feature appears to contradict the concept of the high-frequency residual terms as they have a stiffness-like effect within the frequency range of interest. It is the low-frequency residual terms that have a mass-like effect. In order to be consistent with the correct values, the global parameters have to be included for the new high-frequency residual formulation somehow. What is done is to compensate for the missing global parameters using a chosen, constant, high-frequency pseudo-mass eigenvalue, evaluated over the entire frequency range of interest. This is when the frequency-dependency of the new formulation residual terms is actually taken into account. An automatic way of calculating the high-frequency pseudo-mass eigenvalue is given. Examples are shown to validate the theory and stress the potential of the new approach.
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