elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Shake The Box’ - a 4D PTV algorithm: Accurate and ghostless reconstruction of Lagrangian tracks in densely seeded flows

Schanz, Daniel and Schröder, Andreas and Gesemann, Sebastian (2014) Shake The Box’ - a 4D PTV algorithm: Accurate and ghostless reconstruction of Lagrangian tracks in densely seeded flows. 17th Lisbon 2014 International Symposia on Applications of Laser Techniques to Fluid Mechanics, 07. – 10. July 2014, Lisbon, Portugal.

Full text not available from this repository.

Official URL: Z:\Tagungs_CD\2014\17th_Lisbon_2014\cd2014\finalworks2014\papers\01.5_5_328paper.pdf

Abstract

The ‘Shake The Box’ (STB) PTV - method for the accurate reconstruction of particle tracks in densely seeded flows was first introduced in the scope of the 10th International Symposium on Particle Image Velocimetry (PIV13) in 2013 [Schanz 2013b]. In this first work, it was shown that the proposed method of incorporating the temporal information into the process of particle position reconstruction is able to improve results in various aspects compared to conventionally used techniques. However, only an experimental dataset was available to explore the abilities of the technique [Schanz 2013b]. In order to quantify the key features of the STB-method - and to identify the benefits and drawbacks – a scheme for the creation of synthetic tracks from input - vector volumes was created, allowing the calculation of physically (sufficiently) correct track systems at arbitrary seeding densities and time separations. Projections of such track systems on virtual cameras are used as input data for both STB, as well as an MLOS-SMART [Atkinson 2009] tomographic reconstruction algorithm. The results are compared with respect to positional accuracy of reconstructed particles, occurrence of ghost particles and reconstruction time. It is shown that, after a sufficient number of snapshots to allow for convergence of the algorithm, the STB-method is able to correctly identify nearly all particles in existence, even for high seeding density up to 0,125 particles per pixel (ppp). On the same time, the average position error stays very low (0,023 px for 0.125 ppp) – a gain of more than an order of magnitude compared to MLOS-SMART. The occurrence of ghost particles is almost completely suppressed (ghost level below 0.2 percent for 0.125 ppp). The efficient utilization of the temporal information allows a significant reduction in processing time, with STB being 4 to 6 times faster compared to MLOS-SMART. As the temporal information plays such a dominant role in the STB method – both in the gained results, as well as in the reconstruction process itself – the method cannot be described as pure particle reconstruction, but rather as a method to reconstruct the full temporal development of tracer particles within their residence in the measurement volume. Therefore it is more appropriate to speak of a track reconstruction scheme - or 4D PTV.

Item URL in elib:https://elib.dlr.de/87192/
Document Type:Conference or Workshop Item (Speech)
Additional Information:Paper-Nr.: 01.5_5_328
Title:Shake The Box’ - a 4D PTV algorithm: Accurate and ghostless reconstruction of Lagrangian tracks in densely seeded flows
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Schanz, Danieldaniel.schanz (at) dlr.deUNSPECIFIED
Schröder, Andreasandreas.schroeder (at) dlr.deUNSPECIFIED
Gesemann, SebastianUNSPECIFIEDUNSPECIFIED
Date:2014
Refereed publication:Yes
Open Access:No
Gold Open Access:No
In SCOPUS:No
In ISI Web of Science:No
Page Range:pp. 1-14
Series Name:Conference Proceedings online
Status:Published
Keywords:Time-resolved Tomo PIV, Tomo PTV, Lagrangian particle statistics
Event Title:17th Lisbon 2014 International Symposia on Applications of Laser Techniques to Fluid Mechanics
Event Location:Lisbon, Portugal
Event Type:international Conference
Event Dates:07. – 10. July 2014
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Aeronautics
HGF - Program Themes:fixed-wing aircraft
DLR - Research area:Aeronautics
DLR - Program:L AR - Aircraft Research
DLR - Research theme (Project):L - Simulation and Validation
Location: Göttingen
Institutes and Institutions:Institute of Aerodynamics and Flow Technology > Experimental Methods
Deposited By: Micknaus, Ilka
Deposited On:18 Aug 2014 08:57
Last Modified:21 Oct 2014 13:49

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.