Assessment of continuum breakdown for high-speed chemically reacting wake flows

Sharanya Subramaniam, Krishnan Swaminathan-Gopalan, Kelly Stephani

Research output: Chapter in Book/Report/Conference proceedingConference contribution


The Generalized Chapman Enskog (GCE) breakdown parameters for a two temperature model have been used to assess continuum breakdown for a Mach 24 reacting flow past a circular cylinder. These rigorously derived parameters indicate the regions in the flow field where a solution based on the continuum approximation would no longer accurately reproduce the governing physics. The analysis performed in this work indicates the presence of breakdown regions at the cylinder shock and near the cylinder surface, in the front part of the cylinder. Breakdown regions were also found to extend in the cylinder wake up to the aft cylinder surface. The breakdown parameter indicated that the strong velocity gradients set up in wake region are responsible for distorting the velocity distribution function leading to continuum breakdown. It is also observed that within the recirculation zone adjacent to the cylinder wall, the steep gradients in the temperature are responsible for causing continuum breakdown. A comparison between the rigorously obtained Generalized Chapman Enskog breakdown parameters and the state of the art Gradient-Length-Local Knudsen number reveals that former predict larger breakdown regions, especially in the cylinder wake region.

Original languageEnglish (US)
Title of host publication46th AIAA Thermophysics Conference
PublisherAmerican Institute of Aeronautics and Astronautics Inc, AIAA
ISBN (Print)9781624104350
StatePublished - 2016
Event46th AIAA Thermophysics Conference, 2016 - Washington, United States
Duration: Jun 13 2016Jun 17 2016


Other46th AIAA Thermophysics Conference, 2016
Country/TerritoryUnited States

ASJC Scopus subject areas

  • Aerospace Engineering
  • Mechanical Engineering


Dive into the research topics of 'Assessment of continuum breakdown for high-speed chemically reacting wake flows'. Together they form a unique fingerprint.

Cite this