Editing Particle image velocimetry (section)

==Applications==
PIV has been applied to a wide range of flow problems, varying from the flow over an aircraft wing in a wind tunnel to vortex formation in prosthetic heart valves. 3-dimensional techniques have been sought to analyze turbulent flow and jets.

Rudimentary PIV algorithms based on cross-correlation can be implemented in a matter of hours, while more sophisticated algorithms may require a significant investment of time.  Several open source implementations are available. Application of PIV in the US education system has been limited due to high price and safety concerns of industrial research grade PIV systems.

=== Granular PIV: velocity measurement in granular flows and avalanches ===
PIV can also be used to measure the velocity field of the free surface and basal boundary in a granular flows such as those in shaken containers,<ref>
{{cite journal
 |last1=Lueptow |first1=R.M. |last2=Akonur |first2=A. |last3=Shinbrot |first3=T.
 |year=2000
 |title=PIV for granular flows
 |journal=[[Experiments in Fluids]]
 |volume=28 |issue=2 |pages=183–186
 |doi=10.1007/s003480050023
|bibcode=2000ExFl...28..183L |s2cid=113397348 }}</ref> tumblers<ref>
{{cite journal
 |last1=Jain |first1=N. |last2=Ottino |first2=J.M. |last3=Lueptow |first3=R.M. 
 |year=2002
 |title=An experimental study of the flowing granular layer in a rotating tumbler
 |journal=[[Physics of Fluids]]
 |volume=14 |issue=2 |pages=572–582
 |doi=10.1063/1.1431244
|bibcode = 2002PhFl...14..572J }}</ref> and avalanches.
This analysis is particularly well-suited for nontransparent media such as sand, gravel, quartz, or other granular materials that are common in geophysics. This PIV approach is called "granular PIV". The set-up for granular PIV differs from the usual PIV setup in that the optical surface structure which is produced by illumination of the surface of the granular flow is already sufficient to detect the motion. This means one does not need to add tracer particles in the bulk material.