Numerical Studies for the RAM Accelerator
Abstract
Time-dependent, multidimensional computations were performed to study basic issues related to the structure of shocks, detonations, and modes of combustion affecting the feasibility or performance of the ram accelerator. A focus was on understanding of the structure and stability of oblique detonations generated by oblique shocks in supersonic fuel-air mixtures. The simulations show that steady, oblique detonations can be stabilized in supersonic flows and that they have very complex, multidimensional structures. Basic elements of such detonation structure include: (1) a nonreactive, oblique shock, (2) an induction zone, (3) a set of deflagration waves, and (4) a reactive shock in which the shock front is closely coupled with the energy release. This structure is stable and resilient to disturbances in the flow in a wide range of flow and mixture conditions. The conditions under which the overall detonation structure becomes unstable have also been identified. Preliminary studies which compared extremely resolved Navier-Stokes simulations to a boundary-layer model indicate some fundamental disagreements between the model and the simulations which require further investigations to resolve.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 23, 1992
- Accession Number
- ADA259949
Entities
People
- Chiping Li
- Elaine Oran
- Kazhikathra Kailasanath
Organizations
- United States Naval Research Laboratory