Christian E. Willert – författare

This practical guide provides comprehensive information on PIV. The third edition extends many aspects of Particle image Velocimetry, in particular the tomographic PIV method, high-velocity PIV, Micro-PIV, and accuracy assessment.

This practical guide provides comprehensive information on PIV. The third edition extends many aspects of Particle image Velocimetry, in particular the tomographic PIV method, high-velocity PIV, Micro-PIV, and accuracy assessment.

Particle Image Velocimetry (PIV) is a non-intrusive optical measurement technique which allows capturing several thousand velocity vectors within large flow fields instantaneously. Today, the PIV technique has spread widely and differentiated into many distinct applications, from micro flows over combustion to supersonic flows for both industrial needs and research. Over the past decade the measurement technique and the hard- and software have been improved continuously so that PIV has become a reliable and accurate method for "real life" investigations. Nevertheless there is still an ongoing process of improvements and extensions of the PIV technique towards 3D, time resolution, higher accuracy, measurements under harsh conditions and micro- and macroscales. This book gives a synopsis of the main results achieved during the EC-funded network PivNet 2 as well as a survey of the state of the art of scientific research using PIV techniques in different fields of application.

The development of Particle Image Velocimetry (PIV), a measurement technique, which allows for capturing velocity information of whole ?ow ?elds in fractions of a second, has begun in the eighties of the last century. In 1998, when this book has been published ?rstly, the PIV technique emerged from laboratories to applications in fundamental and industrial research, in par- lel to the transition from photo-graphicalto video recording techniques. Thus this book, whose objective was and is to serve as a practical guide to the PIV technique, found strong interest within the increasing group of users. The early progress made with the PIV technique might best be char- terized by the experience gained during our aerodynamic research at DLR (Deutsches Zentrum fur ¨ Luft- und Raumfahrt) at that time. The ?rst app- cations of PIV outside the laboratory, in wind tunnels, as performed in the mid-eighties were characterized by the following time scales: time required to set up the system and to obtain well focused photo-graphical PIV recordings was 2 to 3 days, time required to process the ?lm was 0. 5 to 1 day, time - quired to evaluate a single photo-graphicalPIV recording by means of optical evaluation methods was 24 to 48 hours. When the ?rst edition of this book was published in 1998, with electronic cameras and computers, it was pos- ble to focus on-line, to capture several recordings per second, and to evaluate a digital recording within seconds.