LES of Combustion Instability in High Pressure Combustors

The Continuously Variable Resonance Chamber (CVRC) experiment at Purdue University exhibits classical signature of longitudinal combustion instability under realistic high pressure conditions. This experiment is simulated here using LES, and the instability mechanism is reproduced and analyzed for a range of inlet duct length. Simulations are focused on understanding the sensitivity of the predictions to the grid and wall conditions, as well as to the choice of chemical mechanism employed.

Personnel Involved: Dr. Reetesh Ranjan, P. Tudisco

Sponsor: AFOSR, NASA/GRC, Rocketdyne-Aerojet


  1. cvrc_temp_heat
  2. Time evolution of temperature and heat-release rate on the central plane in the Continuously Variable Resonance Chamber (CVRC) for an oxidizer injector length of 14cm . Top and bottom halves show contours of temperature and heat-release rate, respectively.


  1. 9cm_rknRay and 14cm_rknRay
  2. Contours of the time-averaged methane reaction rate (top half) and space-local Rayleigh index R (bottom half) on a centerplane.

  3. 9cm_uT and 14cm_uT
  4. Contours of the time-averaged axial velocity (top half) and temperature (bottom half) fields on an azimuthal plane. Solid lines denote iso-lines of U = 0 m/s in the top-half and T = 2000 K in the bottom-half of each subfigure.