Fundamental Non Equilibrium Experiments for Hypersonic Flight
Abstract
The aim of the proposed research is to deliver new insight into non equilibrium flows encountered in high speed flows around hypersonic vehicles. As atmospheric gas passes through the shock wave in front of the vehicle, the large kinetic energy is converted into internal energy. This sudden rise in temperature leads to a variety of chemical reactions and to the excitation of different internal degrees of freedom within the shock layer gas. The inverse happens when a shocked gas is suddenly expanded as is the case around the aft of a vehicle. In both cases, the occurring non equilibrium effects have a significant influence on the aerodynamic characteristics and the surface heat flux of the vehicle. An accurate prediction of these effects is therefore vital for the design of future hypersonic flight vehicles. Non equilibrium occurs as the time scales associated with excitation of internal degrees of freedom and chemical reactions are in the order of the time of flight of the gas particles. The respective rates differ significantly between the various processes which leads to a mixed situation of equilibrium, frozen and states in between these boundaries. This problem has been studied in macro scale experiments of flows around models that highlighted the importance of non equilibrium effects of high enthalpy flows and also the difficulty to accurately predict them. Fundamental micro scale experiments are required to solve the discrepancies seen between experiments and simulations.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 14, 2022
- Source ID
- FA95501917020
Entities
People
- Matthew Mcgilvray
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Oxford