We derive effective equations for wave propagation in a bubbly liquid in a linearized low-frequency regime by a multiple-scale method. The effective equations are valid for finite volume fraction. For periodic bubble configurations, effective equations uniformly valid for small volume fraction are obtained. We compare the results to the ones obtained in a… (More)
We derive a system of effective equations for wave propagation in a bubbly liquid. Starting from a microscopic description, we obtain the effective equations by using Foldy's approximation in a nonlinear setting. We discuss in detail the range of validity of the effective equations as well as some of their properties.
This paper presents a novel integrated control scheme for three-level neutral point clamped (NPC) based PWM rectifier-inverter. Two measures are taken to minimize the size of dc-bus capacitors which are expensive, bulky and have a lifetime limit. Firstly, the direct power control (DPC) for front-end three-level PWM rectifier is applied, which will provide… (More)
Formulas are presented for an incompressible inviscid velocity field V with a vorticity field Ω outside of a rigid sphere and for the far-field sound generation. The velocity V is expressed as the sum of an image velocity v * and a known velocity v in 3 , which is induced by the same vorticity field Ω outside the sphere and the extension Ω = 0 inside. We… (More)
The selection of articles for this issue of the ICASE Research Quarterly departs from the previous policy of presenting technical articles covering a variety of active research areas at ICASE; instead, the articles are devoted to a single topic: convergence acceleration in CFD. The articles for this special issue, solicited by Dr. Jim Jones, Staa Scientist… (More)