DOI: 10.5281/zenodo.1210794
title: Dataset For Journal Jfs: "Near-Wake Characteristics Of Rigid And Membrane Wings In Ground Effect" 2018 By R.Bleischwitz, R.De Kat, B.Ganapathisubramani

description: Complete Dataset for Journal of Fluids and Structures publication:

"Near-wake characteristics of rigid and membrane wings in ground effect" (2018) by, R.Bleischwitz, R.de Kat, B.Ganapathisubramani<br>
Written 01-04-2018<br>
by Robert Bleischwitz (robert.bleischwitz@gmail.com)

General Comments

0.) This specific upload contains the full timeresolved dataset of the JFS-paper (~27GB of timeresolved MATLAB files)

1.) The attached time-resolved-data relates to experimental windtunnel measurements on passive membrane wings for MAVs. The data was aquired between 2012-2016 at the University of Southampton, involving Robert Bleischwitz as PhD student, who was supervised by Roeland de Kat and Bharathram Ganapathisubramani.

2.) The attached data is given time-resolved and time-synchronised at 800Hz over a imaging-period of 5000 images, involving load measurements via a 6-axis load-cell ATI Nano17 /25N, deformation measurements via Digitial Image Processing (high-speed DIC) and stereo flow measurements via two high-speed cameras (high-speed stereo PIV). 

3.) More setup and processing details can be found in the paper "Near-wake characteristics of rigid and membrane wings in ground effect" (2018) by the authors R. Bleischwitz, R. de Kat, B. Ganapathisubramani<br>
Published in:

-Journal of Fluids and Structures: https://doi.org/10.1016/j.jfluidstructs.2018.03.007 

- University of Southampton: http://doi.org/10.5258/SOTON/D0461 

4.) All load/deformation/flow folders contain a README.txt(Use 1st) and Instructions.m (Use 2nd) MATLAB-file, which give further supporting details how to illustrate the time-resolved-data

5.) This specific upload contains the full time-resolved dataset, including:

-Cases:

a.) Rigid and Membrane wings

b.) Height of ground(from trailing edge, in referecne to chord length): h/c=2, 0.25 and 0.1

c.) Angle-of-attack: 10,15,25deg

d.) DATA available (Timeresolved and time-synchronised):

-Loads in high speed (10 kHz)

-Membrane deformations in high speed(800Hz)

-Stereo Flow velocities in wake at high-speed (800Hz)

<strong><em>Abstract of Journal-publication:</em><br>
Wind tunnel measurements are conducted at a Reynolds numbers of Re = 56,000 to examine the characteristics of<br>
near-wake vortices of rigid flat-plates and membrane wings from free-flight into ground–effect conditions. Synchronised<br>
high-speed load cell measurements, digital image correlation and particle image velocimetry are performed to<br>
resolve lift, drag and pitch oscillations simultaneously with membrane deformation and flow dynamics. Flow measurements<br>
are acquired in a crossflow-plane, one chord downstream of the trailing-edge, allowing the examination of<br>
time evolution of the wake and its relationship to the forces and membrane deformation. Membrane wings are found<br>
to delay ground–effect or high angles-of-attack induced tip-vortex break-down and result in larger tip-vortex push-out<br>
(beyond the wing span) compared to rigid flat-plate wings. The leading-edge vortex appears to shed with streamwise<br>
vorticity close to the root of the wing and this frequency of this shedding is found to match with the dominant frequency<br>
observed in membrane fluctuations. In specific resonance conditions, membrane and flow fluctuations are found to<br>
correlate well to the fluctuations in loads and moments.</strong>
description: Link to paper publication: https://doi.org/10.1016/j.jfluidstructs.2018.03.007