fluid mechanics

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Related to Fluid dynamic: Fluid dynamic pressure

fluid mechanics,

branch of mechanicsmechanics,
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 is also a fluid (see states of matterstates of matter,
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 and includes principles from several fields.

Fluid mechanics

The engineering science concerned with the relation between the forces acting on fluids (liquids and gases) and their motions, and with the forces caused by fluids on their surroundings. It is distinct from solid mechanics by virtue of the different responses of fluids and solids to applied forces. In an ideal elastic solid, the deflection or deformation is proportional to the applied stress, whereas a fluid cannot support an applied shear stress unless it is in motion. In most fluids, called simple or newtonian fluids, it is the rate of deformation of the fluid, as opposed to the amount of deformation in a solid, that is proportional to the applied stress. See Fluid flow, Newtonian fluid

Many substances of everyday experience and of engineering importance are found naturally in the fluid state. These include water (liquid and vapor), air (gaseous and liquid), as well as other liquids and gases of natural and industrial importance. The most common fluids are newtonian under most flow conditions.

Fluid mechanics treats the fluid as a continuum, ignoring the fact that it actually consists of individual molecules that may be, in the case of gases, widely spaced compared to molecular dimensions. Nevertheless, the continuum assumption is valid for almost all applications down to the size of bacteria. An exception occurs with gases at very low densities, such as exist in the uppermost regions of the atmosphere. At extremely high altitudes the mean free paths of air molecules—that is, the distances they travel between collisions in random thermal motion—can become as large, or even larger than, the dimensions of a space vehicle, making the assumption of a continuum invalid. See Rarefied gas flow

Fluid mechanics is of fundamental importance to a number of disciplines, including aerospace, chemical, civil, environmental, mechanical, and ocean engineering, as well as to climatology, geology, meteorology, and oceanography. Applications in these fields include, but are not limited to, the study of fluid forces acting on vehicles; flows in natural rivers and artificial channels and the flow of ground water; the dispersion of pollutants in the atmosphere, lakes, rivers, and oceans; the flows in the circulatory and pulmonary systems of humans and animals; the flows in pipelines that carry crude oil and natural gas over many hundreds, or even thousands, of miles from the petroleum fields of their origin to deep-water ports or refineries; the flow of molten plastics or metals filling molds in the manufacture of numerous solid parts; the flow in pumps for water distribution systems; and both hydraulic and gas turbines for power generation and propulsion. Fluid mechanics forms the basis for much of chemistry and physics, and is sometimes applied to such apparently remote fields as cosmology. The fluid mechanical behavior of gases and liquids plays an important role in the dispersion of dissolved or entrained substances. See Aerodynamic force, Aerodynamics, Hydrodynamics

fluid mechanics

[¦flü·əd mə′kan·iks]
The science concerned with fluids, either at rest or in motion, and dealing with pressures, velocities, and accelerations in the fluid, including fluid deformation and compression or expansion.
References in periodicals archive ?
Further, because the fluid dynamic equations are nonlinear, the governing equations must be solved numerically where the problem space is divided into finite cells.
He became an NRL chief scientist and director of the Laboratory for Computational Physics and Fluid Dynamics, a Charter Senior Executive Service position, in 1978.
For example, a thorough understanding of the fluid dynamics of the flow surrounding the Orion Crew Exploration Vehicle - a new spacecraft designed to carry astronauts back to the Moon and later to Mars - is key to a smooth descent and accurate prediction of the landing location.
This project will extend intelligence from small scale laboratory tests to industrial scale piping systems," said Mike Lewis, global lead of Computational Fluid Dynamics with Xodus Group.
This project will extend intelligence from small scale laboratory tests to industrial scale piping systems, said Mike Lewis, Global Lead - Computational Fluid Dynamics with Xodus Group.
Intended as a textbook for courses in computational fluid dynamics at the senior undergraduate or graduate level, this book is a follow-up to Fundamentals of Computational Fluid Dynamics by the same authors, which was published in the series Scientific Computation in 2001.
3) is the vector of external forces and moments, such as weight, buoyant, fluid dynamics which produced by the motion of underwater glide vehicle, and disturbed force which produced by the environment.
Sauber Petronas' Technical Director, Willy Rampf, adds: "Success in F1 requires world-class computational fluid dynamics and a cutting-edge aerodynamic team that is armed with the best tools available, such as the AMD Opteron processor.
This time, to gain more insight, they used computational fluid dynamics (CFD) to analyze both the natural water flow and the behavior of the flow that was mechanically induced.
Arena-flow[TM] is a new computational fluid dynamics (CFD) software package developed for modeling the fluid- and granular-flow behavior controlling sand core blowing.
The Fire Dynamics Simulator is a computational fluid dynamics model which solves a form of the Navier-Stokes equations appropriate for low-speed, thermally-driven flows of smoke and hot gases generated in a fire.
Computational fluid dynamics programs are often cumbersome and erratic, which limits their usefulness.