New theoretical constructs for large eddy simulation (LES) sub-grid scale models allowing modeling shock-turbulence-chemistry interactions in rotating detonation engines
Abstract
Both to increase fuel efficiency and to reduce operating costs and pollutant emissions, continuous design improvements in combustion systems need to be introduced. Conventional propulsion systems utilized nowadays mostly rely on deflagration processes and several variants of the constant-pressure Brayton cycle. However, in thermodynamical terms, energy release under near constant volume conditions, as occurs in rotating detonation engines (RDEs), is more efficient than under constant-pressure ones. Although the advantages of detonation cycles over Brayton ones have been recognized for several decades, the former more efficient cycles have not been implemented yet in practical combustion systems operating in continuous flow operating mode. This occurs because there are several technical challenges that need to be overcome first, before safely and effectively using them in combustion systems relevant to propulsion applications. One of these challenges relates to the strong shockturbulence-chemistry (STC) interactions occurring in such systems, which remain poorly understood. In numerical terms, specifically, computational approaches currently available for modeling such interactions under-resolve the associated physics. In addition, they need high fidelity models to properly capture small-scale turbulence and its interactions with detonation waves and chemical kinetics. Accordingly, this project aims to propose new theoretical constructs for large eddy simulation (LES) sub-grid scale (SGS) models, which allow modeling shock-turbulence-chemistry interactions, accounting for deflagration-to-detonation transition (DDT) processes, and which are applicable in numerical simulations of rotating detonation engines. It is worth noticing here that existing models are currently based on incomplete descriptions of physics at the microscale that typically results in an under resolved simulation. Therefore, the advancements proposed here address this scientific knowledge gap by providing accurate theoretical constructs to conduct fundamental research on compressible reacting flows including denotation waves. After proposed, the referred new theoretical constructs will be used to study physical processes in canonical flow configurations related to pressure-gain combustion systems and rotating detonation engines. Once the basic science questions are addressed, the possible application areas targeted with this project include rotorcraft and scramjets/ramjets for hypersonic propulsion, as well as aircraft and marine gas turbine-based engines. As such, it is expected that the outcomes from this project are utilized to design and use next generation, more compact, and efficient power plants. It should be noticed that the requested project funding will be used to cover expenses for personnel, computer equipment, travels and registration fees for international conferences, and student travels to US to collaborate with the ARL Open Campus program. Finally, this project will be developed in close cooperation with Dr. Luis Bravo and his team at the ARL Vehicle Power and Propulsion Branch.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 12, 2022
- Source ID
- W911NF2210275
Entities
People
- Cesar Celis
Organizations
- Army Contracting Command
- Pontifical Catholic University of Peru
- United States Army