HFSB-seeding for large-scale tomographic PIV in wind tunnels

Journal article (2016)

Authors

Giuseppe Carlo Alp Caridi Aerodynamics - Aerospace Engineering
D. Ragni Wind Energy - Aerospace Engineering
A. Sciacchitano Aerodynamics - Aerospace Engineering
F. Scarano Flow Physics and Technology
Research Group
Aerodynamics (Aerospace Engineering) (TU Delft)
Copyright: © 2016 Giuseppe Carlo Alp Caridi, D. Ragni, A. Sciacchitano, F. Scarano
DOI: https://doi.org/10.1007/s00348-016-2277-7
More Info
expand_more

Published Date

01-12-2016

Language

English

Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Faculty

Aerospace Engineering

Department

Flow Physics and Technology

Research Group

Aerodynamics

Abstract

A new system for large-scale tomographic particle image velocimetry in low-speed wind tunnels is presented. The system relies upon the use of sub-millimetre helium-filled soap bubbles as flow tracers, which scatter light with intensity several orders of magnitude higher than micron-sized droplets. With respect to a single bubble generator, the system increases the rate of bubbles emission by means of transient accumulation and rapid release. The governing parameters of the system are identified and discussed, namely the bubbles production rate, the accumulation and release times, the size of the bubble injector and its location with respect to the wind tunnel contraction. The relations between the above parameters, the resulting spatial concentration of tracers and measurement of dynamic spatial range are obtained and discussed. Large-scale experiments are carried out in a large low-speed wind tunnel with 2.85 × 2.85 m2 test section, where a vertical axis wind turbine of 1 m diameter is operated. Time-resolved tomographic PIV measurements are taken over a measurement volume of 40 × 20 × 15 cm3, allowing the quantitative analysis of the tip-vortex structure and dynamical evolution.

Files

Art_3A10.1007_2Fs00348_016_227... (pdf)
(pdf | 2.52 Mb)
Unknown license