Everything about Shear Stress totally explained
Shear stress is a
stress state where the
stress is
parallel or
tangential to a face of the material, as opposed to
normal stress when the stress is
perpendicular to the face. The variable used to denote shear stress is
(
tau).
Physical quantities of shear stress are measured in force divided by area. In
SI, the
unit is the
pascal (Pa) or newtons per square meter. In
United States customary units, shear stress is also commonly measured in pounds-force per square inch (psi) or kilopounds-force per square inch (ksi). The area is always the area resisting the shear, and not the area that the force is acting on. These two areas are always at right angles.
There are two forms of shear stress: direct shear and beam shear.
Direct Shear
The formula for shear stress in a direct shear is:
»
where
» is the
dynamic viscosity of the fluid,
is the velocity of the fluid along the boundary, and
» is the height of the boundary.
Diverging fringe shear stress sensor
This relationship can be exploited to measure the wall shear stress. If a sensor could directly measure the gradient of the velocity profile at the wall, then multiplying by the
dynamic viscosity would yield the shear stress. Such a sensor was demonstrated by A. A. Naqwi and W. C. Reynolds. The interference pattern generated by sending a beam of light through two parallel slits forms a network of linearly diverging fringes that seem to originate from the plane of the two slits (see
double-slit experiment). As a particle in a fluid passes through the fringes, a receiver detects the reflection of the fringe pattern. The signal can be processed, and knowing the fringe angle, the height and velocity of the particle can be extrapolated.
Further Information
Get more info on 'Shear Stress'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://shear_stress.totallyexplained.com">Shear stress Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |
