Dataset for journal JFS: "Near-wake characteristics of rigid and membrane wings in ground effect" 2018 by R.Bleischwitz, R.de Kat, B.Ganapathisubramani

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
Written 01-04-2018
by Robert Bleischwitz ([e-mail])

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
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)

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