At supersonic speeds, shock waves create steep gradients in the density of the flow field. These large gradients have been shown to adversely affect the accuracy of Shack-Hartmann Wavefront Sensor (SHWFS) during wavefront reconstruction. This is caused by higher-order beam distortions within the lenslet. In the presented work, the wavefront of a collimated beam propagating through a local shock region over a partially protruding cylinder body was measured using SHWFS and off-axis Digital Holography Wavefront Sensor (DHWFS). These measurements were taken simultaneously allowing for direct comparison. Further study was done on computational and post-processing methods of handling the higher order aberrations caused by the shock, as well as studying their effects on the resulting wavefront. By varying the incoming transonic Mach numbers, the shock strength and spatial extent could be adjusted, thus providing multiple scenarios for comparison. The experimental data presented in this work provides valuable insight into shock-induced effects on the resulting wavefront. These results help to further support the development of new methods for mitigating the adverse effects of shocks on well-established measurement methods such as SHWFS and off-axis DHWFS in similar applications.
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