Library Subscription: Guest
Begell Digital Portal Begell Digital Library eBooks Journals References & Proceedings Research Collections
Visualization of Mechanical Processes: An International Online Journal


ISSN Online: 2152-209X

Visualization of Mechanical Processes: An International Online Journal

DOI: 10.1615/VisMechProc.2013007554

Digital holographic interferometry at F4-ONERA hypersonic wind tunnel

Jean-Michel Desse
ONERA, The French Aerospace Lab, 5, boulevard Paul Painleve, F-59045 Lille Cedex, France
Jacques Soutade
ONERA, The French Aerospace Lab, Centre du Fauga-Mauzac, F-31410 Mauzac, France
Paul Viguier
ONERA, The French Aerospace Lab, Centre du Fauga-Mauzac, F-31410 Mauzac, France
Pascal Picart
LAUM, Laboratoire d'Acoustique de l'Universite du Maine, Rue Aristote, F-72085 Le Mans, France
Marc Ferrier
ONERA, The French Aerospace Lab, Centre de Palaiseau, Chemin de la Huniere, F-91761 Palaiseau, France
Laurent Serre
ONERA, The French Aerospace Lab, Centre de Palaiseau, Chemin de la Huniere, F-91761 Palaiseau, France

ABSTRACT

The feasibility of digital holographic interferometry using a CW laser at 532nm and a Photron APX camera is demonstrated in the F4-ONERA hypersonic wind tunnel. This optical technique is used to point out the possible combustion of a small hydrogen jet in the shock layer developed on the model. The optical technique generates in the field under analysis, interference micro-fringes which are used as carrier spatial frequency. The FFT2D processing leads to obtain the field of the optical thickness. If the flow is assumed to be two-dimensional, the map of the refractive index can be estimated. The adjustment of the optical bench is easy to implement and the results obtained with this technique can be used for several interesting comparisons. From the phase difference maps, the holographic images and schlieren images in the x- and y directions can be recalculated, which is not possible with a conventional schlieren optical setup. In addition, if the characteristics of the ionized gas are well known, the value of the gas density upstream and in the shock layer can be estimated.