Accession Number : ADA599340


Title :   Numerical Modeling of Compressible Flow and Its Control


Descriptive Note : Interim rept. 1 Jan 2012-1 Jan 2014


Corporate Author : AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AEROSPACE SYSTEMS DIR


Personal Author(s) : Poggie, Jonathan


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a599340.pdf


Report Date : Mar 2014


Pagination or Media Count : 201


Abstract : This report describes work carried out on numerical modeling of high Mach number flows and their control. Two main technical areas were addressed: nanosecond-pulse, dielectric barrier discharge flow control actuators, and large-scale unsteadiness in separated shock-wave/boundary-layer interactions. Numerical simulations of experiments in the Ohio State University Mach 5 tunnel on control of a cylinder flow with a plasma actuator revealed the interaction of the disturbance generated by the actuator with the bow shock, and ruled out sidewall interactions as a major influence on the experiments. High-fidelity fluid simulations of nanosecond-pulse discharges demonstrated the importance of rapid relaxation of excited neutrals and recombination of ions in generating the flow disturbance. Comparisons of fluid simulations with particle-in-cell simulations showed good agreement, confirming the appropriateness of the fluid approach. In a supersonic compression ramp flow, a gliding discharge plasma actuator was found to be very effective in reducing the extent of separation and the low-frequency content of the turbulent fluctuations. This low-frequency content was examined in data from wind tunnel experiments, Hypersonic International Flight Research Experimentation flight test 1 (HiFIRE-1), and large-eddy simulations, and was found to agree with a theory developed by Plotkin that represents the separation bubble as a frequency-selective amplifier. This approach to understanding of the physics of separation unsteadiness, combined with effective flow control actuators, shows promise for mitigating fatigue loading on high Mach number aircraft.


Descriptors :   *COMPRESSIBLE FLOW , *MACH NUMBER , *NUMERICAL ANALYSIS , ACTUATORS , ALGORITHMS , BOUNDARY LAYER , COMPUTATIONAL FLUID DYNAMICS , GLOW DISCHARGES , LOW FREQUENCY , PLASMAS(PHYSICS) , RECOMBINATION REACTIONS , SHOCK WAVES , SUPERSONIC FLOW , WIND TUNNEL TESTS


Subject Categories : Numerical Mathematics
      Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE