This paper is concerned with the analysis and design of an integrated passive and active control system for reducing the haul truck noise. By using a passive enclosure with two open ends and fiberglass inner surface, a three-dimensional noise radiation problem of the engine noise is shaped to a simple problem of noise radiation from the open ends above 200 Hz. Below 200Hz where the transmission...

The x-ray radiation shielding requirements beyond the first optics enclosure have been considered for the beam transport of the 2-ID-B and 2-ID-C branch lines of Sector 2 (SRI-CAT) of the APS. The first three optical components (mirrors) of the 2-ID-B branch are contained within the shielded first optics enclosure. Calculations indicate that scattering of the primary synchrotron beam by beamlin...

Loudspeaker arrays are increasingly being used in a variety of applications where there is a restriction on the electrical power consumption and the array must be robust to changes in the acoustic environment. Previous work has demonstrated that the efficiency and robustness of a two-source endfire loudspeaker array can be improved by acoustically coupling the two loudspeakers via a common encl...

mixed convection is a fundamentally significant heat transfer mechanism that occurs in selection industrial and technological applications. in this study, first the laminar mixed convection inside rectangular enclosure with moving wall and aspect ratio=10 is modeled and then the results are compared with other investigate. after showing varity of results, the investigation is continued with tur...

Air conditioners are commonly used to keep electronics cool in various areas, such as industrial automation, telecommunication equipment, security and defense systems as well as other indoor and outdoor electronics applications. The electronics may be housed in protective enclosures, where air conditioners deliver cooled air to keep the entire enclosure at desired temperatures for optimum elect...

In this work, to characterize the radiated emission from electronic circuits in shielding enclosure, an improved electric dipole-based source reconstruction method (SRM) is developed. Moreover, by resorting reconstructed equivalent source, estimation of electromagnetic interference (EMI) between different circuit modules enclosure can be conveniently and accurately evaluated. Different free-spa...

A transonic air stream flowing over a rectangular cavity or enclosure is unsteady. At certain flow conditions, large scale oscillations develop in the shear layer which, for an open cavity, spans across the whole enclosure. The convected shear layer instabilities interact with the cavity geometry, they generate resonance, and induce large amplitude wall pressure fluctuations, aerodynamic pressu...

Title of Dissertation: ANALYSIS AND MITIGATION OF ELECTROMAGNETIC NOISE IN RESONANT CAVITIES AND APERTURES Lin Li, Doctor of Philosophy, 2004 Dissertation directed by: Associate Professor Omar Ramahi, Mechanical Engineering The trend of low voltage in electronics circuits and boards makes them vulnerable to electromagnetic interference (EMI). Furthermore, higher speed (clock rate) leads to fast...

This study analyzed that the penetration of electromagnetic waves through an unknown opening in a large enclosure generated standing within enclosure, thereby reducing its shielding characteristics. A 3D numerical analysis confirmed performance can be improved by using absorbers to reduce wave. was verified experimentally.