English
Related papers

Related papers: Intuitive Derivation of Reynolds Number

200 papers

The hydrodynamic and thermal characteristics of a freely-vibrating circular cylinder in mixed convection flow are numerically investigated at low Reynolds numbers. The numerical investigations are conducted for a range of parameters, Ur =…

Fluid Dynamics · Physics 2020-07-22 Bin Liu

The active mass density in Einstein's theory of gravitation in the analog of Poisson's equation in a local inertial system is proportional to $\rho+3p/c^2$. Here $\rho$ is the density of energy and $p$ its pressure for a perfect fluid. By…

General Relativity and Quantum Cosmology · Physics 2009-11-11 J. Ehlers , I. Ozsvath , E. L. Schucking , Y. Shang

A special initial condition for (1+1)-dimensional Burgers equation is considered. It allows to obtain new analytical solutions for an arbitrary low viscosity as well as for the inviscid case. The viscous solution is written as a rational…

Mathematical Physics · Physics 2019-10-15 V. I. Avrutskiy , V. P. Krainov

We consider the flow of a Newtonian fluid in a three-dimensional domain, rotating about a vertical axis and driven by a vertically invariant horizontal body-force. This system admits vertically invariant solutions that satisfy the 2D…

Fluid Dynamics · Physics 2023-07-19 Basile Gallet

The energy method, also known as the Reynolds-Orr equation, is widely utilized in predicting the unconditional stability threshold of shear flows owing to the zero contribution of nonlinear terms to the time derivative of perturbation…

Fluid Dynamics · Physics 2023-11-01 Péter Tamás Nagy

Tortuosity ($T$) is a parameter describing an average elongation of fluid streamlines in a porous medium as compared to free flow. In this paper several methods of calculating this quantity from lengths of individual streamlines are…

Fluid Dynamics · Physics 2015-05-27 Artur Duda , Zbigniew Koza , Maciej Matyka

The paper is devoted to the study of the motion of one-dimensional rigid bodies during a free fall in a quasi-Newtonian hyperviscous fluid at low Reynolds number. We show the existence of a steady solution and furnish sufficient conditions…

Mathematical Physics · Physics 2016-03-23 Giulio G. Giusteri , Alfredo Marzocchi , Alessandro Musesti

In this paper we apply the entropy principle to the relativistic version of the differential equations describing a standard fluid flow, that is, the equations for mass, momentum, and a system for the energy matrix. These are the second…

Mathematical Physics · Physics 2018-02-22 Hans Wilhelm Alt

Heat and mass transport is generally closely correlated to momentum transport in shear flows. This so-called Reynolds analogy between advective heat or mass transport and momentum transport hinders efficiency improvements in engineering…

Fluid Dynamics · Physics 2021-02-17 Geert Brethouwer

We simulate thermal convection in a two-dimensional square box using the no-slip condition on all boundaries, and isothermal bottom and top walls and adiabatic sidewalls. We choose 0.1 and 1 for the Prandtl number $Pr$ and vary the Rayleigh…

Fluid Dynamics · Physics 2025-07-23 Ambrish Pandey , Katepalli R. Sreenivasan

Rotating Rayleigh--B\'enard convection is an oft-employed model system to evaluate the interplay of buoyant forcing and Coriolis forces due to rotation, an eminently relevant interaction of dynamical effects found in many geophysical and…

We propose a reduced-order model for the instantaneous hydrodynamic force on a cylinder. The model consists of a system of two ordinary differential equations (ODEs), which can be integrated in time to yield very accurate histories of the…

Fluid Dynamics · Physics 2024-10-21 Osama A. Marzouk

We determine the Strouhal number (hereafter St), which is essentially a nondimensional measure of the correlation time, from numerical calculations of convection. We use two independent methods to estimate St. Firstly, we apply the minimal…

Astrophysics · Physics 2008-11-26 P. J. Käpylä , M. J. Korpi , M. Ossendrijver , I. Tuominen

The Lorentz transformations are represented on the ball of relativistically admissible velocities by Einstein velocity addition and rotations. This representation is by projective maps. The relativistic dynamic equation can be derived by…

Classical Physics · Physics 2010-08-23 Yaakov Friedman

Extreme Value Theory (EVT) is exploited to determine the global stability threshold $R_g$ of plane Couette flow --the flow of a viscous fluid in the space between two parallel plates-- whose laminar or turbulent behavior depends on the…

Dynamical Systems · Mathematics 2014-03-24 Davide Faranda , Valerio Lucarini , Paul Manneville , Jeroen Wouters

Direct numerical simulations of turbulent pipe flow with transverse wall oscillation (WWO) and with no transverse wall oscillation (NWO) are carried out at friction Reynolds numbers Re{\tau} = 170, 360, and 720. The period and amplitude of…

Fluid Dynamics · Physics 2024-07-18 Daniel Coxe , Yulia Peet , Ronald Adrian

We simulate the space-time dynamics of high-energy collisions based on a microscopic kinetic description, in order to determine the range of applicability of an effective description in relativistic viscous hydrodynamics. We find that…

High Energy Physics - Phenomenology · Physics 2024-02-12 Clemens Werthmann , Victor E. Ambruş , Sören Schlichting

The Lorenz number (L) contained in the Wiedemann-Franz law represents the ratio of two kinetic parameters of electronic charge carriers: the electronic contribution to the thermal conductivity (K_el) and the electrical conductivity (sigma),…

Materials Science · Physics 2022-12-05 Yi Wang , Jorge Paz Soldan Palma , Shun-Li Shang , Long-Qing Chen , Zi-Kui Liu

A new Strouhal-Reynolds number relationship, $St=1/(A+B/Re)$, has been recently proposed based on observations of laminar vortex shedding from circular cylinders in a flowing soap film. Since the new $St$-$Re$ relation was derived from a…

Fluid Dynamics · Physics 2017-08-16 Ildoo Kim , X. L. Wu

We consider $O(N)$ $g\varphi^4$ theory with the coupling $g$ being large, and calculate shear viscosity to entropy density ratio ($\eta/s$). The final result for $\eta/s$ has a form remarkably similar to that obtained from string theory…

High Energy Physics - Phenomenology · Physics 2016-05-23 Namit Mahajan