Increasing Accuracy in Super-Resolution PIV
Abstract
In the development of new measurement techniques, increasing the resolution has always been one of the main goals. For the moment, cross-correlation algorithms such as PIV, are limited by the size of the interrogation areas. Algorithms of hybrid PIV-PTV processing, so called Super Resolution methods, are about to be mature and have shown an increase in the spatial response. The present work is addressing the accuracy issue of such methods. An approach that correlates individual particle images is developed and it is referred as the IPC method. It aims at improving the efficiency compared to the classical approach using estimators of the successive particle locations. Examples of application in vortical flows are presented aiming at discussing the ability to characterize coherent structures. Ideal cases of vortices are simulated with synthetic images. This work presents also measurements of the flow field behind a backward facing step at low Re (Reh=5000) performed in a low speed wind tunnel (U0=3.75 m/s, h=2cm, expansion ratio=1.2). Vortical structures are extracted and results obtained from the two approaches (correlation PIV, hybrid PIV-PTV) are compared.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2005
- Accession Number
- ADA471496
Entities
People
- A. Stitou
- M. L. Riethmuller
- R. Theunissen
Organizations
- von Kármán Institute for Fluid Dynamics