Transition Within a Hypervelocity Boundary Layer on a 5-Degree Half-Angle Cone in Air/CO_2 Mixtures
Laminar to turbulent transition on a smooth 5-degree half angle cone at zero angle of attack is investigated computationally and experimentally in hypervelocity flows of air, carbon dioxide, and a mixture of 50% air and carbon dioxide by mass. Transition N factors above 10 are observed for air flows. At comparable reservoir enthalpy and pressure, flows containing carbon dioxide are found to transition up to 30% further downstream on the cone than flows in pure air in terms of x-displacement, and up to 38% and 140%, respectively, in terms of the Reynolds numbers calculated at edge and reference conditions.
© 2013 by the California Institute of Tehcnology. Published by the American Institute of Aeronautics and Astronautics, Inc., with permission. The authors thank Mr. Nick Parziale for his assistance in running T5, Mr. Bahram Valiferdowsi for his work with design, fabrication, and maintenance, and Prof. Hans Hornung for his advice and support. The experimental portion of this project was sponsored by the Air Force Office of Scientific Research under award number FA9550-10-1-0491 and the NASA/AFOSR National Center for Hypersonic Research. The computational work was sponsored by the Air Force Office of Scientific Research grant FA9550-10-1-0352. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. The views expressed herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of AFOSR, Sandia, or the U.S. Government.
Accepted Version - aiaa2013-ASM-Jewell.pdf