Geoscience Reference
In-Depth Information
Particle Imaging Velocimetry and Its
Applications in Hydraulics: A State-of-the-Art
Review
Cristiana Di Cristo
1
Introduction
In the last three decades, the advanced technologies related of optics, laser, elec-
tronics, video and computers have facilitated the development of the image-based
techniques for flow visualization and quantitative measurements. Different image-
based instruments, under the generic name of Particle Imaging Velocimetry (PIV),
were developed and applied to a variety of fluid mechanics applications. PIV is
widely applied in aerodynamics and hydraulic research because it is a nonintrusive
technique able to provide quantitative measurement of fluid velocity over a rela-
tively large surface with measurements documented at a large number of points
simultaneously. PIV delivers whole-field velocity measurements, distinguishing
the method from all the previous velocity measurement methods, such as the
contemporary Laser Doppler Velocimetry and Hot Wire Anemometer that can
only be used to gather single point measurements. With the PIV, the velocity is
measured in an indirect way, by estimating the displacement of flow markers or
patterns in small regions (interrogation areas) in a sequence of recorded images.
Besides PIV, various image velocimetry methods were developed, such as the
Particle Tracking Velocimetry (PTV), which suites better specific objectives of
scientific investigations.
The chapter starts with a brief presentation of the historical development and of
the basic principles of Particle Imaging Velocimetry (PIV) methods. The second
part describes examples of PIV implementation in different hydraulic research
applications. No attempt has been made herein to make the presentation of the
methods exhaustive. The interested readers are directed to the comprehensive PIV
literature where they can find extensive descriptions of the principles, compo-
nents, and operational aspects (Adrian
1991
; Raffael et al.
2007
). A good source
