A QMU approach for characterizing the operability limits of air-breathing hypersonic vehicles

The operability limits of a supersonic combustion engine for an air-breathing hypersonic vehicle are characterized using numerical simulations and an uncertainty quantification methodology. The time-dependent compressible flow equations with heat release are solved in a simplified configuration. Verification, calibration and validation are carried out to assess the ability of the model to reproduce the flow/thermal interactions that occur when the engine unstarts due to thermal choking. quantification of margins and uncertainty (QMU) is used to determine the safe operation region for a range of fuel flow rates and combustor geometries.

► In this work we introduce a method to study the operability limits of hypersonic scramjet engines. ► The method is based on a calibrated heat release model. ► It accounts explicitly for uncertainties due to flight conditions and model correlations. ► We examine changes due to the combustor geometry and fuel injection.