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Lecture

Control volume - Reynolds Transport Theorem

In course

BIOENG-312: Fluid mechanics (for SV)

This introductory course on fluids mechanics presents the basics concepts in fluids statics, dynamics and kinematics. ...

Description

This lecture covers the concepts of control volume and Reynolds Transport Theorem (RTT) in fluid mechanics. It explains the Eulerian and Lagrangian descriptions of flowing fluids, flow field characterization, examples of flow fields, and the application of RTT to conservation of mass. The derivation of RTT, continuity equation, and examples of compressible fluid flow are discussed in detail.

Instructor

Nikolaos Stergiopoulos

Education MTE, Managing the Technology Enterprise Program (2000), IMD, Lausanne Ph.D. in Biomedical Engineering & Engineering Mechanics (1990) Iowa State University, Ames, Iowa. MS in Biomedical Engineering (1987) Iowa State University, Ames, Iowa. Diploma in Mechanical Engineering (1985) National Technical University of Athens. Professional Activities 2002 - present: Professor and director of LHTC 2010 - present: Founder and director of Rheon Medical SA, Préverenges, Switzerland 2008 - present: Founder and director of Antlia S.A., PSE-C, EPFL campus, Switzerland 1998 - 2007: Founder and Scientific Director of EndoArt S.A., Lausanne, Switzerland 1996 - 2002: Assistant professor at the Biomedical Engineering Laboratory, Swiss Federal Institute of Technology, Lausanne, Switzerland. 1991 - 1996: Research Associate at Swiss Federal Institute of Technology - Lausanne 1990 - 1991: Lecturer, Iowa State University

Official source

Ontological neighbourhood

Physics

Mechanics: Fluid mechanics

Related concepts (32)

Fluid dynamics

In physics, physical chemistry and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids—liquids and gases. It has several subdisciplines, including aerodynamics (the study of air and other gases in motion) and hydrodynamics (the study of liquids in motion). Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modelling fission weapon detonation.

Fluid mechanics

Fluid mechanics is the branch of physics concerned with the mechanics of fluids (liquids, gases, and plasmas) and the forces on them. It has applications in a wide range of disciplines, including mechanical, aerospace, civil, chemical, and biomedical engineering, as well as geophysics, oceanography, meteorology, astrophysics, and biology. It can be divided into fluid statics, the study of fluids at rest; and fluid dynamics, the study of the effect of forces on fluid motion.

Incompressible flow

In fluid mechanics or more generally continuum mechanics, incompressible flow (isochoric flow) refers to a flow in which the material density is constant within a fluid parcel—an infinitesimal volume that moves with the flow velocity. An equivalent statement that implies incompressibility is that the divergence of the flow velocity is zero (see the derivation below, which illustrates why these conditions are equivalent). Incompressible flow does not imply that the fluid itself is incompressible.

Reynolds number

In fluid mechanics, the Reynolds number (Re) is a dimensionless quantity that helps predict fluid flow patterns in different situations by measuring the ratio between inertial and viscous forces. At low Reynolds numbers, flows tend to be dominated by laminar (sheet-like) flow, while at high Reynolds numbers, flows tend to be turbulent. The turbulence results from differences in the fluid's speed and direction, which may sometimes intersect or even move counter to the overall direction of the flow (eddy currents).

Newtonian fluid

A Newtonian fluid is a fluid in which the viscous stresses arising from its flow are at every point linearly correlated to the local strain rate — the rate of change of its deformation over time. Stresses are proportional to the rate of change of the fluid's velocity vector. A fluid is Newtonian only if the tensors that describe the viscous stress and the strain rate are related by a constant viscosity tensor that does not depend on the stress state and velocity of the flow.

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