CaltechAUTHORS
  A Caltech Library Service

Pressure from 2D snapshot PIV

Van der Kindere, J. W. and Laskari, A. and Ganapathisubramani, B. and de Kat, R. (2019) Pressure from 2D snapshot PIV. Experiments in Fluids, 60 (2). Art. No. 32. ISSN 0723-4864. PMCID PMC6394750. http://resolver.caltech.edu/CaltechAUTHORS:20190125-115026899

[img] PDF - Published Version
Creative Commons Attribution.

2921Kb
[img] Video (MPEG) - Supplemental Material
Creative Commons Attribution.

6Mb

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20190125-115026899

Abstract

In this study, we quantify the accuracy of a simple pressure estimation method from 2D snapshot PIV in attached and separated flows. Particle image velocimetry (PIV) offers the possibility to acquire a field of pressure instead of point measurements. Multiple methods may be used to obtain pressure from PIV measurements, however, the current state-of-the-art requires expensive equipment and data processing. As an alternative, we aim to quantify the efficacy of estimating instantaneous pressure from snapshot (non-time resolved) two-dimensional planar PIV (the simplest type of PIV available). To make up for the loss of temporal information, we rely on Taylor’s hypothesis (TH) to replace temporal information with spatial gradients. Application of our approach to high-resolution 2D velocity data of a turbulent boundary layer flow over ribs shows moderate to good agreement with reference pressure measurements in average and fluctuations. To assess the performance of the 2D TH method beyond average and fluctuation statistics, we acquired a time-resolved measurement of the same flow and determined temporal correlation values of the pressure from our method with reference measurements. Overall, the correlation attains good values for all measured locations. For comparison, we also applied two time-resolved approaches, which attained values of correlation similar to our approach. The performance of the 2D TH method is further assessed on 3D time-resolved velocity data for a turbulent boundary layer and compared with 3D methods. The root-mean-square (RMS) pressure fluctuations of the 2D TH, 3D TH and 3D pseudo-Lagrangian methods closely follow the pressure fluctuation distribution from DNS. These observations on the RMS pressure estimates are further supported by similar analysis on synthetic PIV data (based on DNS) of a turbulent channel flow. The values of spatial correlation between the 2D TH method and the DNS pressure fields in this case, are similar to the temporal correlations achieved in the turbulent flow over the ribs. Finally, we discuss the accuracy of instantaneous pressure estimates and provide a rule of thumb to determine regions where the pressure fluctuation estimate from the 2D TH methods is likely to fail.


Item Type:Article
Related URLs:
URLURL TypeDescription
https://doi.org/10.1007/s00348-019-2678-5DOIArticle
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6394750PubMed CentralArticle
ORCID:
AuthorORCID
de Kat, R.0000-0002-6851-4409
Additional Information:© The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Received: 20 March 2018; Revised: 20 December 2018; Accepted: 3 January 2019; First Online: 25 January 2019. European Research Council (ERC Grant agreement no. 277472), EU-FP7 project NIOPLEX (Grant agreement no. 605151), EPSRC project EP/R010900/1, EU-H2020 project HOMER (Grant agreement no. 769237), RdK was partially supported by a Leverhulme Early Career Fellowship (Grant no. ECF-2013-259).
Group:GALCIT
Funders:
Funding AgencyGrant Number
European Research Council (ERC)277472
European Research Council (ERC)605151
Engineering and Physical Sciences Research Council (EPSRC)EP/R010900/1
European Research Council (ERC)769237
Leverhulme TrustECF-2013-259
PubMed Central ID:PMC6394750
Record Number:CaltechAUTHORS:20190125-115026899
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20190125-115026899
Official Citation:Van der Kindere, J.W., Laskari, A., Ganapathisubramani, B. et al. Exp Fluids (2019) 60: 32. https://doi.org/10.1007/s00348-019-2678-5
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:92475
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:25 Jan 2019 19:58
Last Modified:18 Mar 2019 15:32

Repository Staff Only: item control page