Accession Number : ADA504177


Title :   Hypersonic Wind-Tunnel Measurements of Boundary-Layer Pressure Fluctuations


Descriptive Note : Master's thesis


Corporate Author : PURDUE UNIV LAFAYETTE IN SCHOOL OF AERONAUTICS AND ASTRONAUTICS


Personal Author(s) : Casper, Katya M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a504177.pdf


Report Date : Aug 2009


Pagination or Media Count : 178


Abstract : During atmospheric reentry, hypersonic vehicles are subjected to high levels of boundary-layer pressure fluctuations. To improve understanding and prediction of these fluctuations, measurements of surface pressure fluctuations on a seven-degree sharp cone at zero angle of attack were conducted in Sandia's Hypersonic Wind Tunnel under noisy flow and in Purdue University's Boeing/AFOSR Mach-6 Quiet Tunnel under noisy and quiet flow. Fluctuations under laminar boundary layers reflected tunnel noise levels. Laminar boundary-layer measurements under quiet flow were an order of magnitude lower than under noisy flow. Transition on the model only occurred under noisy flow, and fluctuations peaked during transition. The transition location, marked by the peak, depended on tunnel noise parameters.


Descriptors :   *MEASUREMENT , *HYPERSONIC WIND TUNNELS , *PRESSURE MEASUREMENT , *BOUNDARY LAYER , THESES , HYPERSONIC VEHICLES , ANGLE OF ATTACK , QUIET , TRANSITIONS , REENTRY VEHICLES , NOISE , INSTABILITY , PARAMETERS , ATMOSPHERE ENTRY , VARIABLE PRESSURE , FLOW


Subject Categories : Research and Experimental Aircraft
      Test Facilities, Equipment and Methods
      Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE