Added mass

About: Added mass is a research topic. Over the lifetime, 2849 publications have been published within this topic receiving 47899 citations.

Stability of the kinematically coupled $\beta$- scheme for fluid-structure interaction problems in hemodynamics

Abstract: It is known that classical Dirichlet-Neumann loosely coupled partitioned schemes for uid-structure interaction (FSI) problems are unconditionally unstable for certain combinations of physical and geometric parameters that are relevant in hemodynamics. It was shown by Causin, Gerbeau, and Nobile [17] that these instabilities are associated with the \added-mass eect". The \added mass eect" was studied in [17] by considering the simplest FSI problem which captures the main features responsible for the instabilities of classical Dirichlet-Neumann loosely coupled schemes. By considering the same test problem, the present work shows that a novel, partitioned, loosely coupled scheme, recently introduced in [11], called the kinematically coupled -scheme, does not suer from the added mass eect for any 2 [0; 1], and is unconditionally stable for all the parameter values in the problem. Numerical results are presented for a fully nonlinear benchmark FSI problem in hemodynamics of Formaggia et al. [30]. The results show that the scheme is stable for this benchmark problem even for the parameter values well within the parameter range for which the classical Dirichlet-Neumann schemes are unconditionally unstable. The main contribution of this work is in explicitly showing how the implicit enforcement of the kinematic coupling condition and the inclusion of the structure inertia into the uid sub-problem avoid the presence of the added mass eect in the kinematically-coupled -scheme.

Bio-mass sensor using an electrostatically actuated microcantilever in a vacuum microchannel

Abstract: The present work focuses on the dynamic analysis of a bio-mass sensor. The main component of this microsystem is a cantilever beam placed in a vacuum microchannel with a proof mass attached to its end. The rigid mass is coupled to an electrode to capacitively drive the beam. The operating principle is based on detecting the shift in the resonance frequency of the microbeam to measure the mass of a cell deposited on the sensing tip. We show that the present system enables easy detection and measurement of the added mass. To gain insight into the microsystem sensitivity to variations in its parameters, such as the gap distance and tip mass, as well as the use of higher-order modes, we examine their effects on the variation of the resonance frequency shift with respect to the added mass.