Streamsurface

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In fluid dynamics a stream surface is a surface across which no flow occurs. A stream surface may be one of two types:

In scientific visualization a stream surface is the 3D generalization of a streamline. It is the union of all streamlines seeded densely on a curve. Like a streamline, a stream surface is used to visualize flows – three-dimensional flows in this case. Specifically, it is "the locus of an infinite set of such curves [streamlines], rooted at every point along a continuous originating line segment." [1]

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<span class="mw-page-title-main">Bernoulli's principle</span> Principle relating to fluid dynamics

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A foil is a solid object with a shape such that when placed in a moving fluid at a suitable angle of attack the lift is substantially larger than the drag. If the fluid is a gas, the foil is called an airfoil or aerofoil, and if the fluid is water the foil is called a hydrofoil.

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In scientific visualization skin friction lines are used to visualize flows on 3D-surfaces. They are obtained by calculating the streamlines of a derived vector field on the surface, the wall shear stress. Skin friction arises from the friction of the fluid against the "skin" of the object that is moving through it and forms a vector at each point on the surface. A skin friction line is a curve on the surface tangent to skin friction vectors. A limit streamline is a streamline where the distance normal to the surface tends to zero. Limit streamlines and skin friction lines coincide.

Airflow, or air flow, is the movement of air. The primary cause of airflow is the existence of air. Air behaves in a fluid manner, meaning particles naturally flow from areas of higher pressure to those where the pressure is lower. Atmospheric air pressure is directly related to altitude, temperature, and composition.

Boundary conditions in fluid dynamics are the set of constraints to boundary value problems in computational fluid dynamics. These boundary conditions include inlet boundary conditions, outlet boundary conditions, wall boundary conditions, constant pressure boundary conditions, axisymmetric boundary conditions, symmetric boundary conditions, and periodic or cyclic boundary conditions.

<span class="mw-page-title-main">Surface</span> Outermost or uppermost layer of a physical object or space

A surface, as the term is most generally used, is the outermost or uppermost layer of a physical object or space. It is the portion or region of the object that can first be perceived by an observer using the senses of sight and touch, and is the portion with which other materials first interact. The surface of an object is more than "a mere geometric solid", but is "filled with, spread over by, or suffused with perceivable qualities such as color and warmth".

References

  1. Hultquist, J. P. M. (1992). Constructing stream surfaces in steady 3D vector fields. IEEE Computer Society Press Los Alamitos, CA, USA. pp. 171–178. ISBN   978-0-8186-2896-2.