Differences of turbulence modulation by heavy particles on solid wall and erodible bed surface

2021 ◽  
Vol 33 (11) ◽  
pp. 113305
Author(s):  
Ping Wang ◽  
Qingqing Wei ◽  
Xiaojing Zheng
Keyword(s):  
Solid Wall ◽  
Heavy Particles ◽  
Turbulence Modulation

scholarly journals Modelling of turbulence modulation in particle- or droplet-laden flows

2012 ◽  
Vol 706 ◽  
pp. 251-273 ◽  
Author(s):  
Daniel W. Meyer
Keyword(s):  
Isotropic Turbulence ◽  
Density Ratio ◽  
Joint Probability ◽  
Stokes Number ◽  
Navier Stokes ◽  
Grid Turbulence ◽  
Heavy Particles ◽  
Turbulence Modulation ◽  
Modelling Framework ◽  
Liquid Flows

AbstractAddition of particles or droplets to turbulent liquid flows or addition of droplets to turbulent gas flows can lead to modulation of turbulence characteristics. Corresponding observations have been reported for very small particle or droplet volume loadings ${\Phi }_{v} $ and therefore may be important when simulating such flows. In this work, a modelling framework that accounts for preferential concentration and reproduces isotropic and anisotropic turbulence attenuation effects is presented. The framework is outlined for both Reynolds-averaged Navier–Stokes (RANS) and joint probability density function (p.d.f.) methods. Validations are performed involving a range of particle and flow-field parameters and are based on the direct numerical simulation (DNS) study of Boivin, Simonin & Squires (J. Fluid Mech., vol. 375, 1998, pp. 235–263) dealing with heavy particles suspended in homogeneous isotropic turbulence (Stokes number $\mathit{St}= O(1{\unicode{x2013}} 10)$, particle/fluid density ratio ${\rho }_{p} / \rho = 2000$, ${\Phi }_{v} = O(1{0}^{- 4} )$) and the experimental investigation of Poelma, Westerweel & Ooms (J. Fluid Mech., vol. 589, 2007, pp. 315–351) involving light particles ($\mathit{St}= O(0. 1)$, ${\rho }_{p} / \rho \gtrsim 1$, ${\Phi }_{v} = O(1{0}^{- 3} )$) settling in grid turbulence. The development in this work is restricted to volume loadings where particle or droplet collisions are negligible.

Turbulence modulation by finite-size heavy particles in a downward turbulent channel flow

2021 ◽  
Vol 33 (6) ◽  
pp. 063321
Author(s):  
Yan Xia ◽  
Zhaowu Lin ◽  
Dingyi Pan ◽  
Zhaosheng Yu
Keyword(s):  
Channel Flow ◽  
Finite Size ◽  
Turbulent Channel Flow ◽  
Heavy Particles ◽  
Turbulence Modulation

Action of Non-Linear Waves at a Solid Wall

1977 ◽  
Author(s):  
Mohamed S. Nasser ◽  
John A. McCorquodale
Keyword(s):  
Solid Wall ◽  
Linear Waves ◽  
Non Linear

Connected Post-Wall (C-PW) Waveguide for Efficient Design of Broad Wall Slots by Using Equivalent Solid-Wall Waveguide

2010 ◽  
Vol E93-C (7) ◽  
pp. 1038-1046
Author(s):  
Jae-Ho LEE ◽  
Kimio SAKURAI ◽  
Jiro HIROKAWA ◽  
Makoto ANDO
Keyword(s):  
Solid Wall ◽  
Efficient Design

Turbulence Modulation in a Simplex Spray

1997 ◽  
Vol 24 (1-3) ◽  
pp. 97-107 ◽  
Author(s):  
Wei-Hsiang Lai ◽  
Muh-Rong Wang ◽  
D. Y. Huang
Keyword(s):  
Turbulence Modulation

РАДИАЦИОННО СТОЙКОЕ КМОП СТАТИЧЕСКОЕ ОЗУ 16 МБИТ 1657РУ2У

2020 ◽  
Vol 96 (3s) ◽  
pp. 169-174
Author(s):  
Ю.М. Герасимов ◽  
Н.Г. Григорьев ◽  
А.В. Кобыляцкий ◽  
Я.Я. Петричкович
Keyword(s):  
Total Dose ◽  
Heavy Particles ◽  
Topological Features ◽  
Radiation Hardened ◽  
Latch Up

Рассматриваются архитектурные, схемотехнические и конструктивно-топологические особенности асинхронного радиационно стойкого ОЗУ 1657РУ2У емкостью 16 Мбит с организацией (1Мx16)/(2Mx8), изготавливаемого по коммерческой КМОП-технологии объемного кремния уровня 130 нм. СБИС ОЗУ нечувствительна к эффекту «защелкивания», имеет повышенные дозовую стойкость и сбоеустойчивость при воздействии отдельных ядерных частиц (ОЯЧ), протонов и нейтронов (ТЧ). The paper highlights architectural, schematic and topological features of the radiation hardened 16 Mbit CMOS SRAM with configurable organization 1Mx16/2Mx8, which is immune to latch-up and with improved total dose and heavy particles tolerance.

scholarly journals Settling Velocity of Microplastics Exposed to Wave Action

2021 ◽  
Vol 9 (2) ◽  
pp. 142
Author(s):  
Annalisa De Leo ◽  
Laura Cutroneo ◽  
Damien Sous ◽  
Alessandro Stocchino
Keyword(s):  
Laboratory Experiments ◽  
Settling Velocity ◽  
Transport Model ◽  
Stokes Drift ◽  
Inertial Effects ◽  
Sea Waves ◽  
Heavy Particles ◽  
Analytical Formulation ◽  
Simplified Approach ◽  
Remote Areas

Microplastic (MP) debris is recognized to be one of the most serious threats to marine environments. They are found in all seas and oceanic basins worldwide, even in the most remote areas. This is further proof that the transport of MPs is very efficient. In the present study, we focus our attention on MPs’ transport owing to the Stokes drift generated by sea waves. Recent studies have shown that the interaction between heavy particles and Stokes drift leads to unexpected phenomena mostly related to inertial effects. We perform a series of laboratory experiments with the aim to directly measure MPs’ trajectories under different wave conditions. The main objective is to quantify the inertial effect and, ultimately, suggest a new analytical formulation for the net settling velocity. The latter formula might be implemented in a larger scale transport model in order to account for inertial effects in a simplified approach.

Sign in / Sign up

Export Citation Format

Share Document