Calibration of the HEG and Its Use for Verification of Real Gas Effects in High Entalpy Flows

Abstract

This paper deals with the experimental possibilities, provided by the new high enthalpyh wind tunnel HEG, to study the effects of oxygen and nitrogen dissociation in experiments where this reaction occurs over a sufficiently short distance in stagnating flows. The current capability of the HEG does not cover the real gas effects of combustion in high enthalpy flows. First, the capabilitiesof the various types of experimental facilities for generating high enthalpy flows will be discussed and compared with capability achieved in the HEG. Second, the particulars of the large facility its capability to operate in tailored mode and the drawbacks of relatively large test times at high density and enthalpy will be discussed in the light of the latest calibration experiments. After the discussion of the calibration status of the HEG, samples ofaerothermodynamics tests performed in the HEG will be discussed. Someof these experiments are reconfirmations of experiments like flow over blunt bodies performed in the Australian tunnels T3 and T4 wherethe difference lies in the new instrumentation applied to the same flow problems, others are new studies of external aerothermodynamics like the experiments on shock/shock interactions. The significance of the dissociation effects in the above experiments is pointed out.