Thin perforated Steel Plate Shear (SPS) Walls are among the most common types of energy dissipating systems. The applied holes reduce the shear strength of the plate and allow to decrease the profile size of the members at the boundary of the panel when these systems are used in the typical design of structures. On the other hand, the different fracture locations of these panels are visible whe...

Preliminary note Uniformity of the radial air jet issuing from the ceiling vortex diffuser with side entry plenum box was investigated experimentally. Two different cases of diffuser plenum box design were used: plenum box with perforated plate and plenum box without perforated plate. Air jet velocities were measured under isothermal conditions circumferentially around a diffuser. It was found ...

Introduction: Micro-perforated absorbents are one of the structures that are widely used nowadays. The sound absorption mechanism is performed by viscous energy losses in the cavities on the plate. In this study, the acoustic properties of non-flat perforated panels in oblique angle was investigated in numerical method. Material and Methods: This paper examined the effect of the surface shape ...

The main objective of this paper is to study the characteristics of flow-induced noise in high pressure reducing valve (HPRV) and to provide some guidance for noise control. Based on computational fluid dynamics (CFD), numerical method was used to compute flow field. Ffowcs Williams and Hawkings Model was applied to obtain acoustic signals. The unsteady flow field shows that noise sources are l...

The study of the acoustic effect of perforated plates by Large-Eddy Simulations is reported. The ability of compressible Large-Eddy Simulations to provide data on the flow around a perforated plate and the associated acoustic damping is demonstrated. In particular, assumptions of existing models of the acoustic effect of perforated plate are assessed thanks to the Large-Eddy Simulations results...

Low-frequency noise pollution in substations has a significant impact on the physical and mental health of workers. Reduction low-frequency is an urgent problem to solve for researchers. In this paper, different structures Al 2 O 3 -polyurethane composites micro-perforated plate were constructed, effects cavity depth, perforated plate, foam position sound absorption properties comprehensively i...

unglazed transpired solar collectors are widely used for heating outside air directly, these days. pre-heating ventilation air for large spaces and heating air for crop drying, are some of the applications of these kinds of collectors. the outside air is drawn straight from ambient, uniformly through the whole surface of a perforated absorber (transpired, dark-colored plate) exposed to the sun....

The flow and acoustic fields of jets at a Mach number 3.1 impinging on plate the jet nozzle exit, where is diameter, have been investigated using highly resolved large-eddy simulations. perforated with hole diameter , or . full-plate free-jet cases also considered. pressure levels are highest for non-perforated decrease as increases. Compared free jet, they higher by about 5 dB full plate, 4 3 ...