Phase-measuring laser holographic interferometer for use in high speed flows

Phase-measurement techniques have been applied to a dual-plate laser holographic interferometer (LHI). This interferometer has been used to determine the flow-field densities in a variety of two-dimensional and axisymmetric flows. In particular, LHI has been applied in three different experiments: flow-field measurements inside two-dimensional scramjet inlet, flow over a blunt cone, and flow over an indented nose shape. Comparisons of experimentally determined densities with computational results indicate that, when phase-measurement techniques are used in conjunction with state-of-the-art image-processing instrumentation, holographic interferometry can be a diagnostic tool with high resolution, high accuracy, and rapid data retrieval