Shape factor (boundary layer flow)
- Shape factor (boundary layer flow)
A shape factor is used in boundary layer flow to determine the nature of the flow.
:
where H is the shape factor, is the displacement thickness and θ is the momentum thickness. Displacement thickness is defined as the distance that the surface would have to displace outwards in an inviscid flow in order to give the same mass flow rate deficit as that which exists in the boundary layer. Momentum thickness is defined as the distance that the wall would have to displace outwards in an inviscid flow in order to give the same momentum deficit (per unit width) of the mass flow rate.
The higher the value of H, the stronger the adverse pressure gradient. Large values of H implies that boundary layer separation is about to occur.
Further reading
* F.M. White, "Fluid Mechanics", McGraw-Hill, 5th Edition, 2003.
* B.R. Munson, D.F. Young and T.H. Okiishi, "Fundamentals of Fluid Mechanics", John Wiley, 4th Edition, 2002.
* B. Massey and J. Ward-Smith, "Mechanics of Fluids", Taylor and Francis, 8th Edition, 2006.
Wikimedia Foundation.
2010.
Look at other dictionaries:
Shape factor — can refer to one of number of values in physics, engineering or image analysis. Typically, a shape factor refers to a value that is affected by an object s shape but is independent of its dimensions.In physics: * A band pass filter performance… … Wikipedia
Boundary layer — For the anatomical structure, see Boundary layer of uterus. Boundary layer visualization, showing transition from laminar to turbulent condition In physics and fluid mechanics, a boundary layer is that layer of fluid in the immediate vicinity of… … Wikipedia
Boundary-layer thickness — This page describes some parameters used to measure the properties of boundary layers. Consider a stationary body with a turbulent flow moving around it, like the semi infinite flat plate with air flowing over the top of the plate. At the solid… … Wikipedia
Dimensionless quantity — In dimensional analysis, a dimensionless quantity or quantity of dimension one is a quantity without an associated physical dimension. It is thus a pure number, and as such always has a dimension of 1.[1] Dimensionless quantities are widely used… … Wikipedia
Reynolds number — In fluid mechanics and heat transfer, the Reynolds number mathrm{Re} is a dimensionless number that gives a measure of the ratio of inertial forces ({old mathrm V} ho) to viscous forces (mu / L) and, consequently, it quantifies the relative… … Wikipedia
Drag (physics) — Shape and flow Form drag Skin friction 0% 100% 10% 90% … Wikipedia
climate — /kluy mit/, n. 1. the composite or generally prevailing weather conditions of a region, as temperature, air pressure, humidity, precipitation, sunshine, cloudiness, and winds, throughout the year, averaged over a series of years. 2. a region or… … Universalium
fluid mechanics — an applied science dealing with the basic principles of gaseous and liquid matter. Cf. fluid dynamics. [1940 45] * * * Study of the effects of forces and energy on liquids and gases. One branch of the field, hydrostatics, deals with fluids at… … Universalium
Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… … Universalium
Gas — This article is about the physical properties of gas as a state of matter. For the uses of gases, and other meanings, see Gas (disambiguation). Ga … Wikipedia
