Performance analysis of a strut-aided hypersonic scramjet by full-scale IDDES modeling

The uninstalled performance of a full-scale scramjet operating over Mach 7 to 10 and altitudes of 28 to 40 km was numerically analyzed by using high-fidelity Improved Delayed Detached Eddy Simulation (IDDES) with 125.10 million cells and Dynamic Zone Flamelet model (DZFM) with 21,294 flamelet zones. The inviscid thrust can be well correlated with dynamic pressure in the form of a gaussian function, whereas the viscous drag increases almost linearly with dynamic pressure. For the examined scramjet, net thrust is achieved for the low dynamic pressure range below 37 kPa and the high range above 55 kPa. The rule of mixed is burnt is observed, and the final combustion efficiencies vary from 66% to 82%. The upstream propagation of combustion occurs for most of the cases in the current strut-based combustor, and unstart occurs for the case of Mach 7 at 30 km. (C) 2021 Elsevier Masson SAS. All rights reserved.

Automated summary

The study found that a full-scale scramjet engine can achieve net thrust in the range of low dynamic pressure below 37 kPa and high range above 55 kPa, with combustion efficiencies varying from 66% to 82%. The rule of mixed is burnt was observed along with upstream propagation of combustion. However, unstart may occur in specific cases, such as Mach 7 at 30 km altitude.