Application of Holographic Interferometry to Density Field Determination in Transonic Corner Flow

Abstract

The present report is believed to be the first quantitative measurements obtained by holographic interferometry of the density field in transonic corner flow. The technique offers a new method to obtain quantitative transonic flow measurements without disrupting the flow. Finite fringe interferometry has been used to investigate the threedimensional density field about a partially transparent wing-body structure. The resulting asymmetric density field and shock wave structure are shown to be an accurate representation of the phenomena encountered in aerodynamic corner flow. The double pulse technique allows the interferogram to be taken through the transparent nonflat optical elements in the wing. The depth focusing and angular viewing properties of a hologram although of possible use in transonic flows were not used in the present experiment.