This work aims at studying the nonlinear dynamics of drill strings using lumped-parameter method (LPM). The study is based on good consistency results test problem where model longitudinal vibrations a horizontal string with static compressive load left end considered. In this paper, applied to discretize linear and models lateral vertical under effect supersonic gas flow. obtained are verified...

The sound emission of thin-walled radiating components is a common objective of structural optimisation. Acoustic measures are not implemented in common FE-codes. Thus, different velocitiy based measures will be compared: the kinetic energy, the equivalent radiated power (ERP) and the lumped parameter model (LPM). The most common approach the ERP is based on the sound intensity in normal direct...

A hydraulic engine mount (HEM) is an advanced tuned mass damper (TMD) system used to isolate the noise and vibration from chassis. This paper aims design a semiactive HEM based on TMD model, which only tunes damping without affecting other lumped parameters of system. Firstly, dynamic equations modeled as are derived linear parameter model (LPM). Each analyzed identify relevant that affect damp...

PurposeInvasive hemodynamic ramp studies have been shown to decrease the rates of left ventricular assist device (LVAD) complications however hemocompatibility related adverse events (HRAE) still remain unacceptably high. Computational fluid dynamics (CFD) allows for a more thorough analysis shear rate (SR) and stress (SS) which influences endothelial function thrombotic potential.MethodsAn inv...

Numerical modeling and experimentation are used at Xerox Office Group to design, optimize, and verify the fluid dynamic behavior of phase-change ink jets, including the individual jets in a print head. A typical model of an ink jet is based upon lumped-parameter (no spatial variation) assumptions. While quite accurately predicting the main Helmholz resonant frequency (a key performance measure)...