Development of a Simple Compact Photodiode Array for Use with Linear Array-FLDI

This work presents a simplified and cost-effective modification for the signal sampling configuration used by previously described linear array focus laser differential interferometers (LA-FLDI). In this configuration, the photodiodes used previously are decoupled from their amplifier boards allowing for a compact sensor arrangement that eliminates the need for fiber optic transport of the individual signals. In this work, the frequency response of the updated photodiode configuration measured are compared against the previous configuration. LA-FLDI measurements will also be carried out with the new array on a flared cone model boundary layer of a Mach 6 blowdown tunnel. These results are compared with expected values and with data collected previously in the same facility.