نتایج جستجو برای: اجسام bluff

تعداد نتایج: 2468  

Journal: :Physics of Fluids 2022

Experimental studies dealing with the wake of isolated stationary bluff bodies are reviewed. After briefly recalling pioneering works in this domain, paper focuses on recent research conducted latest experimental methods and techniques. The review encompasses a range topics, including effects body geometry (non-circular cross sections non-uniformity spanwise direction), steady unsteady (periodi...

مقدمه: سندرم دیسترس تنفسی از علل شایع مرگ و میر دوره نوزادی است و علت آن عدم وجود مقدار کافی سورفاکتانت در بافت ریه جنین می باشد. چندین روش آزمایشگاهی برای تعیین بلوغ ریه جنین وجود دارد. هدف از این مطالعه، انجام تست شمارش اجسام لاملار جهت پیشگویی رسیدگی ریه جنین و ابتلا به سندرم دیسترس تنفسی در ریه نوزادان نارس می باشد. روش کار: مطالعه کاربردی حاضر از نوع بررسی مقطعی است که به مدت 6 ماه در سال ...

2008
M. Minguez R. Pasquetti E. Serre

The paper addresses the Large-Eddy Simulation (LES) of the turbulent wake of the Ahmed car model. To this endwe use a Fourier-Chebyshevmulti-domain solver and the LES capability is implemented through the use of the Spectral Vanishing Viscosity (SVV) method, completed with a near-wall correction. A “pseudo-penalization” technique is used to model the bluff body. Comparisons of the present SVV-L...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2009
Marcus Roper Michael P Brenner

The nonlinearity of the Navier-Stokes equations makes predicting the flow of fluid around rapidly moving small bodies highly resistant to all approaches save careful experiments or brute force computation. Here, we show how a linearization of the Navier-Stokes equations captures the drag-determining features of the flow and allows simplified or analytical computation of the drag on bodies up to...

2017
Christopher D. Golden Katherine L. Seto Madan M. Dey Oai L. Chen Jessica A. Gephart Samuel S. Myers Matthew Smith Bapu Vaitla Edward H. Allison

Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, United States, Harvard University Center for the Environment, Cambridge, MA, United States, Department of Environmental Science, Policy and Management, University of California, Berkeley, Berkeley, CA, United States, Department of Agriculture, Texas State University, San Marcos, TX, United States, 5 Aquac...

2011
S. Bajalan A. Shadaram N. Hedayat A. Shams Taleghani

The interaction between wakes of bluff body and airfoil have profound influences on system performance in many industrial applications, e.g., turbo-machinery and cooling fan. The present work investigates the effect of configuration include; airfoil’s angle of attack, transverse and inline spacing of the models, on frequency behavior of the cylinder’s near-wake. The experiments carried on under...

Journal: :IEEE Trans. Automat. Contr. 2007
Ole Morten Aamo Andrey Smyshlyaev Miroslav Krstic Bjarne A. Foss

An exponentially convergent observer is designed for a linearized Ginzburg-Landau model of vortex shedding in viscous flow past a bluff body. Measurements are restricted to be taken collocated with the actuation which is applied on the cylinder surface. The observer is used in conjuction with a state feedback boundary controller designed in previous work to attenuate vortex shedding. Simulation...

Journal: :J. Comput. Physics 2011
Johannes Tophøj Rasmussen Georges-Henri Cottet Jens H. Walther

We present a novel multiresolution Vortex-In-Cell algorithm using patches of varying resolution. The Poisson equation relating the fluid vorticity and velocity is solved using Fast Fourier Transforms subject to free space boundary conditions. Solid boundaries are implemented using the semi-implicit formulation of Brinkman penalization and we show that the penalization can be carried out as a si...

2010
David J. Olinger

A combined analytical-experimental approach is used. Analytical aspects focus on the continued development of a low-order model that utilizes a series of diffusively coupled circle map oscillators along the cylinder span. This coupled map lattice has been extended to include control logic to develop a very efficient low order model for control studies in cylinder wake flows. On the experimental...

2016
C. Mimeau

A vortex method with penalization is proposed in order to simulate three-dimensional incompressible bluff body flows. This approach combines the robustness of vortex methods and the flexibility of penalization methods to impose boundary conditions on the obstacle. Far field boundary conditions are handled in a FFT-based Poisson solver. A validation of the proposed numerical method is carried ou...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید