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Moody Chart
In engineering, the Moody chart or Moody diagram (also Stanton diagram) is a graph in non-dimensional form that relates the Darcy–Weisbach friction factor ''f''''D'', Reynolds number Re, and surface roughness for fully developed flow in a circular pipe. It can be used to predict pressure drop or flow rate down such a pipe. History In 1944, Lewis Ferry Moody plotted the Darcy–Weisbach friction factor against Reynolds number Re for various values of relative roughness ε / ''D''. This chart became commonly known as the Moody chart or Moody diagram. It adapts the work of Hunter Rouse but uses the more practical choice of coordinates employed by R. J. S. Pigott, whose work was based upon an analysis of some 10,000 experiments from various sources. Measurements of fluid flow in artificially roughened pipes by J. Nikuradse were at the time too recent to include in Pigott's chart. The chart's purpose was to provide a graphical representation of the function of C. F. Colebr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimensionless Numbers
Dimensionless quantities, or quantities of dimension one, are quantities implicitly defined in a manner that prevents their aggregation into units of measurement. ISBN 978-92-822-2272-0. Typically expressed as ratios that align with another system, these quantities do not necessitate explicitly defined units. For instance, alcohol by volume (ABV) represents a volumetric ratio; its value remains independent of the specific units of volume used, such as in milliliters per milliliter (mL/mL). The number one is recognized as a dimensionless base quantity. Radians serve as dimensionless units for angular measurements, derived from the universal ratio of 2π times the radius of a circle being equal to its circumference. Dimensionless quantities play a crucial role serving as parameters in differential equations in various technical disciplines. In calculus, concepts like the unitless ratios in limits or derivatives often involve dimensionless quantities. In differential geom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laminar Flow
Laminar flow () is the property of fluid particles in fluid dynamics to follow smooth paths in layers, with each layer moving smoothly past the adjacent layers with little or no mixing. At low velocities, the fluid tends to flow without lateral mixing, and adjacent layers slide past one another smoothly. There are no cross-currents perpendicular to the direction of flow, nor eddies or swirls of fluids. In laminar flow, the motion of the particles of the fluid is very orderly with particles close to a solid surface moving in straight lines parallel to that surface. Laminar flow is a flow regime characterized by high momentum diffusion and low momentum convection. When a fluid is flowing through a closed channel such as a pipe or between two flat plates, either of two types of flow may occur depending on the velocity and viscosity of the fluid: laminar flow or turbulent flow. Laminar flow occurs at lower velocities, below a threshold at which the flow becomes turbulent. The thresh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 (the study of air and other gases in motion) and (the study of water and other liquids in motion). Fluid dynamics has a wide range of applications, including calculating forces and moment (physics), moments on aircraft, determining the mass flow rate of petroleum through pipeline transport, pipelines, weather forecasting, predicting weather patterns, understanding nebulae in interstellar space, understanding large scale Geophysical fluid dynamics, geophysical flows involving oceans/atmosphere and Nuclear weapon design, modelling fission weapon detonation. Fluid dynamics offers a systematic structure—which underlies these practical disciplines—that embraces empirical and semi-empirical laws derived from flow measurement and used to solve practical problems. The solution to a fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Darcy Friction Factor Formulae
In fluid dynamics, the Darcy friction factor formulae are equations that allow the calculation of the ''Darcy friction factor'', a dimensionless quantity used in the Darcy–Weisbach equation, for the description of friction losses in pipe flow as well as open-channel flow. The Darcy friction factor is also known as the ''Darcy–Weisbach friction factor'', ''resistance coefficient'' or simply ''friction factor''; by definition it is four times larger than the Fanning friction factor. Notation In this article, the following conventions and definitions are to be understood: * The Reynolds number Re is taken to be Re = ''V'' ''D'' / ν, where ''V'' is the mean velocity of fluid flow, ''D'' is the pipe diameter, and where ν is the kinematic viscosity μ / ρ, with μ the fluid's Dynamic viscosity, and ρ the fluid's density. * The pipe's relative roughness ε / ''D'', where ε is the pipe's effective roughness height and ''D'' the pipe (inside) diameter. * ''f'' stands for the D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friction Loss
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Types of friction include dry, fluid, lubricated, skin, and internal -- an incomplete list. The study of the processes involved is called tribology, and has a history of more than 2000 years. Friction can have dramatic consequences, as illustrated by the use of friction created by rubbing pieces of wood together to start a fire. Another important consequence of many types of friction can be wear, which may lead to performance degradation or damage to components. It is known that frictional energy losses account for about 20% of the total energy expenditure of the world. As briefly discussed later, there are many different contributors to the retarding force in friction, ranging from asperity deformation to the generation of charges and changes in local structure. When two bodies in contact move relative to each other, due to these variou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fanning Friction Factor
The Fanning friction factor (named after American engineer John T. Fanning) is a dimensionless number used as a local parameter in continuum mechanics calculations. It is defined as the ratio between the local shear stress and the local flow kinetic energy density: f = \frac where : is the local Fanning friction factor (dimensionless); : is the local shear stress (units of pascals (Pa) = kg/m, or pounds per square foot (psf) = lbm/ft); : is the bulk dynamic pressure (Pa or psf), given by: q = \frac \rho u^2 :: is the density of the fluid ( kg/m or lbm/ft) :: is the bulk flow velocity (m/s or ft/s) In particular the shear stress at the wall can, in turn, be related to the pressure loss by multiplying the wall shear stress by the wall area ( 2 \pi R L for a pipe with circular cross section) and dividing by the cross-sectional flow area ( \pi R^2 for a pipe with circular cross section). Thus \Delta P = f \frac q = f \frac \rho u^2 Fanning friction factor formula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fanning Equation
Fanning may refer to: * Fanning (bees), a behaviour of worker bees signalling an entrance to a hive * Fanning (firearms), a shooting technique in which one hand holds a revolver and the other hits the hammer repeatedly * Fanning (surname) * Fanning friction factor, a dimensionless number used in fluid flow calculations * Fan dance, a dance art form * USS ''Fanning'', ships of the United States Navy Places * Cape Fanning, Antarctica * Fanning Ridge, South Georgia Island * Fanning, Kansas, United States * Fanning, Missouri, United States * Tabuaeran Tabuaeran, also known as Fanning Island, is an atoll that is part of the Line Islands of the central Pacific Ocean and part of the island nation of Kiribati. The land area is , and the population in 2015 was 2,315. The maximum elevation is abou ..., also known as Fanning Atoll or Fanning Island, one of the Line Islands of the central Pacific Ocean See also * Fan (other) {{Disambiguation, geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colebrook Equation
In fluid dynamics, the Darcy friction factor formulae are equations that allow the calculation of the ''Darcy friction factor'', a dimensionless quantity used in the Darcy–Weisbach equation, for the description of friction losses in pipe flow as well as open-channel flow. The Darcy friction factor is also known as the ''Darcy–Weisbach friction factor'', ''resistance coefficient'' or simply ''friction factor''; by definition it is four times larger than the Fanning friction factor. Notation In this article, the following conventions and definitions are to be understood: * The Reynolds number Re is taken to be Re = ''V'' ''D'' / ν, where ''V'' is the mean velocity of fluid flow, ''D'' is the pipe diameter, and where ν is the kinematic viscosity μ / ρ, with μ the fluid's Dynamic viscosity, and ρ the fluid's density. * The pipe's relative roughness ε / ''D'', where ε is the pipe's effective roughness height and ''D'' the pipe (inside) diameter. * ''f'' stands for the D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hagen–Poiseuille Equation
In fluid dynamics, the Hagen–Poiseuille equation, also known as the Hagen–Poiseuille law, Poiseuille law or Poiseuille equation, is a physical law that gives the pressure drop in an incompressible and Newtonian fluid in laminar flow flowing through a long cylindrical pipe of constant cross section. It can be successfully applied to air flow in lung alveoli, or the flow through a drinking straw or through a hypodermic needle. It was experimentally derived independently by Jean Léonard Marie Poiseuille in 1838 and Gotthilf Heinrich Ludwig Hagen, and published by Hagen in 1839 and then by Poiseuille in 1840–41 and 1846. The theoretical justification of the Poiseuille law was given by George Stokes in 1845. The assumptions of the equation are that the fluid is incompressible and Newtonian; the flow is laminar through a pipe of constant circular cross-section that is substantially longer than its diameter; and there is no acceleration of fluid in the pipe. For velocities a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbulent Flow
In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by Chaos theory, chaotic changes in pressure and flow velocity. It is in contrast to laminar flow, which occurs when a fluid flows in parallel layers with no disruption between those layers. Turbulence is commonly observed in everyday phenomena such as Breaking wave, surf, fast flowing rivers, billowing storm clouds, or smoke from a chimney, and most fluid flows occurring in nature or created in engineering applications are turbulent. Turbulence is caused by excessive kinetic energy in parts of a fluid flow, which overcomes the damping effect of the fluid's viscosity. For this reason, turbulence is commonly realized in low viscosity fluids. In general terms, in turbulent flow, unsteady vortices appear of many sizes which interact with each other, consequently Drag (physics), drag due to friction effects increases. The onset of turbulence can be predicted by the dimensionless Reynolds number, the rati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Darcy Friction Factor
Darcy, Darci or Darcey may refer to different people such as: Science * Darcy's law, which describes the flow of a fluid through porous material * Darcy (unit), a unit of permeability of fluids in porous material * Darcy friction factor in the field of fluid mechanics * Darcy–Weisbach equation used in hydraulics for calculation of the head loss due to friction People * Darcy (surname), a surname (including a list of people with the name) Men * Darci Afonso Jacobi Júnior (born 1979), Brazilian footballer * Darcy Blake (born 1988), Welsh footballer * Darcy Dallas (born 1972), Canadian ice hockey defenceman * Darcy Cameron (born 1995), Australian rules footballer * Darcy Daniher (born 1989), Australian rules footballer * Darci Frigo, Brazilian activist * Darcy Furber, Canadian politician * Darcy Gardiner (born 1995), Australian rules footballer * Darcy Hordichuk (born 1980), professional ice hockey player * Darcy Kuemper (born 1990), professional ice hockey player ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Darcy–Weisbach Equation
In fluid dynamics, the Darcy–Weisbach equation is an Empirical research, empirical equation that relates the head loss, or pressure loss, due to friction along a given length of pipe to the average velocity of the fluid flow for an incompressible fluid. The equation is named after Henry Darcy and Julius Weisbach. Currently, there is no formula more accurate or universally applicable than the Darcy-Weisbach supplemented by the Moody diagram or Colebrook equation. The Darcy–Weisbach equation contains a dimension analysis, dimensionless friction factor, known as the Darcy friction factor. This is also variously called the Darcy–Weisbach friction factor, friction factor, resistance coefficient, or flow coefficient. Historical background The Darcy-Weisbach equation, combined with the Moody chart for calculating head losses in pipes, is traditionally attributed to Henry Darcy, Julius Weisbach, and Lewis Ferry Moody. However, the development of these formulas and charts also involv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
