Investigation of Transition Frequencies of Two Acoustically Coupled Bubbles Using a Direct Numerical Simulation Technique

Investigation of transition frequencies of two acoustically coupled bubbles using a direct numerical simulation technique

The theoretical results regarding the “transition frequencies” of two acoustically interacting bubbles have been verified numerically. The theory provided by Ida [Phys. Lett. A 297 (2002) 210] predicted the existence of three transition frequencies per bubble, each of which has the phase difference of π/2 between a bubble’s pulsation and the external sound field, while previous theories predict...

investigation of thermal comfort properties of woven sport fabric using blend of estabragh fibers

امروزه لباس در نظر ورزشکاران و کسانی که برای اوقات فراغت خود و یا برای رسیدن به اندامی متعادل، ورزش می کنند؛ بسیار با اهمیت است. احساس مطلوب از لباس در زمره خصوصیات راحتی پوشش می باشد. خصوصیات انتقال رطوبت لباس، در ارزیابی راحتی حسی و حرارتی منسوجات تولید شده از آن ها بسیار مهم است. هدف از این تحقیق، معرفی پارچه جدید است که متشکل از الیاف استبرق با خواص منحصر به فرد می باشد. استبرق لیف طبیعی تو...

Investigation of acoustically coupled enclosures using a diffusion-equation model.

Recent application of coupled-room systems in performing arts spaces has prompted active research on sound fields in these complex geometries. This paper applies a diffusion-equation model to the study of acoustics in coupled-rooms. Acoustical measurements are conducted on a scale-model of two coupled-rooms. Using the diffusion model and the experimental results the current work conducts in-dep...

Direct Numerical Simulation of Wall Turbulence with Bubbles

investigation of turbulent kinetic energy redistribution in a channel flow using direct numerical simulation

in this study, the turbulent kinetic energy redistribution process is investigated. to this aim, the direct numerical simulation (dns) of incompressible flow of a newtonian fluid through a channel at a shear reynolds number of reτ = 180 is used to produce a flow data base. then, these data are statistically analyzed. the turbulent kinetic energy redistribution is studied using the pressure-stra...