Physics:Seeding (fluid dynamics)

From HandWiki
Flow around a sphere being visualized by seeding the flow with smoke.
Visualization of hairpin vortex structure, made visible by seeding the flow with colored dye.

Seeding a material is a concept used in fluid dynamics to describe the act of introducing specific particulates or other foreign substances into a stream of fluid being evaluated. An altered fluid will be described as having a seeded flow.[1]

Details

These particulates are generally small enough to be carried by the fluid but large enough to be picked up using a flow visualization technique, such as particle image velocimetry (PIV). In reference to aerodynamic testing, such as wind tunnel testing, water tunnel testing, or any other test investigating the flow of a fluid which may be invisible to the naked eye, seeding a flow is often the only way to take visual measurements. Simple examples of a seeded flow include the introduction of smoke into a low speed wind tunnel to see the general path of the air, or injecting colored dye into a water tunnel to see secondary flow structures such as hairpin vortices.[citation needed]

As stated in The Handbook of Fluid Dynamics, an ideal seeding particle should have uniform properties such that its density is the same as the fluid that it's added to.[1]

See also

References