Holographic interferometry of the flow field between a fin and flat plate.

This study was an attempt to map the density field in a fin-flat plate junction three-dimensionally using holographic interferometry. This investigation has extended the density studies by Matulka [12, 13] and Jagota [3, 4] to include, for the first time, interferometric fringe information obtained through a transparent model in supersonic flow. The fringe information was then inverted by a FORTRAN computer program to produce a plot of the density field around the model. The feasibility of the method was demonstrated. The factors which are thought to have limited the success of the experiment include vibration of the model, fluctuations of the tunnel flow and the fact that the model was somewhat too large in relation to the size of the wind tunnel test section. Schlieren photography was used to look through and around the model and to verify that the same flow was established as was reported by Thomas [23, 24] and Winkelmam [26, 27] . The data reduction of holographic inter ferograms was, for the first time, accomplished using photographic enlargements. This technique is considered to be much easier and more accurate than the one used in the previous investigations. However, the data reduction step, because of the time and labor involved, is considered to be the rate controlling process of the whole analysis.
http://archive.org/details/holographicinter1094516171
Lieutenant, United States Navy
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