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Joseph Boussinesq
Joseph Valentin Boussinesq (; 13 March 1842 – 19 February 1929) was a French mathematician and physicist who made significant contributions to the theory of hydrodynamics, vibration, light, and heat. Biography From 1872 to 1886, he was appointed professor at Faculty of Sciences of Lille, lecturing differential and integral calculus at Institut industriel du Nord (École centrale de Lille). From 1896 to his retirement in 1918, he was professor of mechanics at Faculty of Sciences of Paris. John Scott Russell experimentally observed solitary waves in 1834 and reported it during the 1844 Meeting of the British Association for the advancement of science. Subsequently, this was developed into the modern physics of solitons. In 1871, Boussinesq published the first mathematical theory to support Russell's experimental observation, and in 1877 introduced the KdV equation. In 1876, Lord Rayleigh published his mathematical theory to support Russell's experimental observation. At the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saint-André-de-Sangonis
Saint-André-de-Sangonis (''Sant Andrieu de Sangònis'' in Occitan) is a commune in the Hérault department in the Occitanie region in southern France. Population Sights * Jardin botanique de la Font de Bézombes See also *Communes of the Hérault department The following is a list of the 342 Communes of France, communes of the Hérault Departments of France, department of France. The communes cooperate in the following Communes of France#Intercommunality, intercommunalities (as of 2020): References Communes of Hérault {{Hérault-geo-stub ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Scott Russell
John Scott Russell FRSE FRS FRSA (9 May 1808, Parkhead, Glasgow – 8 June 1882, Ventnor, Isle of Wight) was a Scottish civil engineer, naval architect and shipbuilder who built '' Great Eastern'' in collaboration with Isambard Kingdom Brunel. He made the discovery of the wave of translation that gave birth to the modern study of solitons, and developed the wave-line system of ship construction. Russell was a promoter of the Great Exhibition of 1851. Early life John Russell was born on 9 May 1808 in Parkhead, Glasgow, the son of Reverend David Russell and Agnes Clark Scott. He spent one year at the University of St. Andrews before transferring to the University of Glasgow. It was while at the University of Glasgow that he added his mother's maiden name, Scott, to his own, to become John Scott Russell. He graduated from Glasgow University in 1825 at the age of 17 and moved to Edinburgh where he taught mathematics and science at the Leith Mechanics' Institute, achieving the hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basset–Boussinesq–Oseen Equation
In fluid dynamics, the Basset–Boussinesq–Oseen equation (BBO equation) describes the motion of – and forces on – a small particle in unsteady flow at low Reynolds numbers. The equation is named after Joseph Valentin Boussinesq, Alfred Barnard Basset and Carl Wilhelm Oseen. Formulation The BBO equation, in the formulation as given by and , pertains to a small spherical particle of diameter d_p having mean density \rho_p whose center is located at \boldsymbol_p(t). The particle moves with Lagrangian velocity \boldsymbol_p(t)=\text \boldsymbol_p / \textt in a fluid of density \rho_f, dynamic viscosity \mu and Eulerian velocity field \boldsymbol_f(\boldsymbol,t). The fluid velocity field surrounding the particle consists of the undisturbed, local Eulerian velocity field \boldsymbol_f plus a disturbance field – created by the presence of the particle and its motion with respect to the undisturbed field \boldsymbol_f. For very small particle diameter the latter is locally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stokes Flow
Stokes flow (named after George Gabriel Stokes), also named creeping flow or creeping motion,Kim, S. & Karrila, S. J. (2005) ''Microhydrodynamics: Principles and Selected Applications'', Dover. . is a type of fluid flow where advective inertial forces are small compared with viscous forces. The Reynolds number is low, i.e. \mathrm \ll 1. This is a typical situation in flows where the fluid velocities are very slow, the viscosities are very large, or the length-scales of the flow are very small. Creeping flow was first studied to understand lubrication. In nature this type of flow occurs in the swimming of microorganisms, sperm and the flow of lava. In technology, it occurs in paint, MEMS devices, and in the flow of viscous polymers generally. The equations of motion for Stokes flow, called the Stokes equations, are a linearization of the Navier–Stokes equations, and thus can be solved by a number of well-known methods for linear differential equations. The primary Green's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boussinesq–Basset Force
In a body submerged in a fluid, unsteady forces due to acceleration of that body with respect to the fluid, can be divided into two parts: the virtual mass effect and the Basset force. The Basset force term describes the force due to the lagging boundary layer development with changing relative velocity (acceleration) of bodies moving through a fluid. The Basset term accounts for viscous effects and addresses the temporal delay in boundary layer development as the relative velocity changes with time. It is also known as the "history" term. The Basset force is difficult to implement and is commonly neglected for practical reasons; however, it can be substantially large when the body is accelerated at a high rate. This force in an accelerating Stokes flow has been proposed by Joseph Valentin Boussinesq in 1885 and Alfred Barnard Basset in 1888. Consequently, it is also referred to as the Boussinesq–Basset force. Acceleration of a flat plate Consider an infinitely large plate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reynolds Stresses
In fluid dynamics, the Reynolds stress is the component of the total stress tensor in a fluid obtained from the averaging operation over the Navier–Stokes equations to account for turbulent fluctuations in fluid momentum. Definition The velocity field of a flow can be split into a mean part and a fluctuating part using Reynolds decomposition. We write :u_i = \overline + u_i',\, with \mathbf(\mathbf,t) being the flow velocity vector having components u_i in the x_i coordinate direction (with x_i denoting the components of the coordinate vector \mathbf). The mean velocities \overline are determined by either time averaging, spatial averaging or ensemble averaging, depending on the flow under study. Further u'_i denotes the fluctuating (turbulence) part of the velocity. We consider a homogeneous fluid, whose density ''ρ'' is taken to be a constant. For such a fluid, the components ''τ''ij'' of the Reynolds stress tensor are defined as: :\tau'_ \equiv \rho\,\overline,\, Anothe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscosity
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the internal frictional force between adjacent layers of fluid that are in relative motion. For instance, when a viscous fluid is forced through a tube, it flows more quickly near the tube's axis than near its walls. Experiments show that some stress (such as a pressure difference between the two ends of the tube) is needed to sustain the flow. This is because a force is required to overcome the friction between the layers of the fluid which are in relative motion. For a tube with a constant rate of flow, the strength of the compensating force is proportional to the fluid's viscosity. In general, viscosity depends on a fluid's state, such as its temperature, pressure, and rate of deformation. However, the dependence on some of these properties is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbulence Modeling
Turbulence modeling is the construction and use of a mathematical model to predict the effects of turbulence. Turbulent flows are commonplace in most real life scenarios, including the flow of blood through the cardiovascular system, the airflow over an aircraft wing, the re-entry of space vehicles, besides others. In spite of decades of research, there is no analytical theory to predict the evolution of these turbulent flows. The equations governing turbulent flows can only be solved directly for simple cases of flow. For most real life turbulent flows, CFD simulations use turbulent models to predict the evolution of turbulence. These turbulence models are simplified constitutive equations that predict the statistical evolution of turbulent flows. Closure problem The Navier–Stokes equations govern the velocity and pressure of a fluid flow. In a turbulent flow, each of these quantities may be decomposed into a mean part and a fluctuating part. Averaging the equations gives the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Thomson, 1st Baron Kelvin
William Thomson, 1st Baron Kelvin, (26 June 182417 December 1907) was a British mathematician, mathematical physicist and engineer born in Belfast. Professor of Natural Philosophy at the University of Glasgow for 53 years, he did important work in the mathematical analysis of electricity and formulation of the first and second laws of thermodynamics, and did much to unify the emerging discipline of physics in its contemporary form. He received the Royal Society's Copley Medal in 1883, was its president 1890–1895, and in 1892 was the first British scientist to be elevated to the House of Lords. Absolute temperatures are stated in units of kelvin in his honour. While the existence of a coldest possible temperature ( absolute zero) was known prior to his work, Kelvin is known for determining its correct value as approximately −273.15 degrees Celsius or −459.67 degrees Fahrenheit. The Joule–Thomson effect is also named in his honour. He worked closely with mathematics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philosophical Magazine
The ''Philosophical Magazine'' is one of the oldest scientific journals published in English. It was established by Alexander Tilloch in 1798;John Burnett"Tilloch, Alexander (1759–1825)" Oxford Dictionary of National Biography, Oxford University Press, Sept 2004; online edn, May 2006, accessed 17 Feb 2010 in 1822 Richard Taylor became joint editor and it has been published continuously by Taylor & Francis ever since. Early history The name of the journal dates from a period when "natural philosophy" embraced all aspects of science. The very first paper published in the journal carried the title "Account of Mr Cartwright's Patent Steam Engine". Other articles in the first volume include "Methods of discovering whether Wine has been adulterated with any Metals prejudicial to Health" and "Description of the Apparatus used by Lavoisier to produce Water from its component Parts, Oxygen and Hydrogen". 19th century Early in the nineteenth century, classic papers by Humphry Davy, M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Strutt, 3rd Baron Rayleigh
John William Strutt, 3rd Baron Rayleigh, (; 12 November 1842 – 30 June 1919) was an English mathematician and physicist who made extensive contributions to science. He spent all of his academic career at the University of Cambridge. Among many honors, he received the 1904 Nobel Prize in Physics "for his investigations of the densities of the most important gases and for his discovery of argon in connection with these studies." He served as president of the Royal Society from 1905 to 1908 and as chancellor of the University of Cambridge from 1908 to 1919. Rayleigh provided the first theoretical treatment of the elastic scattering of light by particles much smaller than the light's wavelength, a phenomenon now known as " Rayleigh scattering", which notably explains why the sky is blue. He studied and described transverse surface waves in solids, now known as " Rayleigh waves". He contributed extensively to fluid dynamics, with concepts such as the Rayleigh number (a dimen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lord Rayleigh
John William Strutt, 3rd Baron Rayleigh, (; 12 November 1842 – 30 June 1919) was an English mathematician and physicist who made extensive contributions to science. He spent all of his academic career at the University of Cambridge. Among many honors, he received the 1904 Nobel Prize in Physics "for his investigations of the densities of the most important gases and for his discovery of argon in connection with these studies." He served as president of the Royal Society from 1905 to 1908 and as chancellor of the University of Cambridge from 1908 to 1919. Rayleigh provided the first theoretical treatment of the elastic scattering of light by particles much smaller than the light's wavelength, a phenomenon now known as "Rayleigh scattering", which notably explains why the sky is blue. He studied and described transverse surface waves in solids, now known as "Rayleigh waves". He contributed extensively to fluid dynamics, with concepts such as the Rayleigh number (a dimensio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
