FOUNDATIONAL FUEL TECHNOLOGIES IN SUPPORT OF ROTATING DETONATION ENGINE PROPULSION
Abstract
The overall goal of this effort is to advance rotating detonation engine (RDE) technology for Navy applications by evaluating the detonation behavior of nitrate ester-based fuels. To achieve this goal, I propose a 1-year effort where my team will systematically detonate nitrate ester-based fuels, with mixtures of hydrogen and air, in a narrow detonation channel (representative of an RDE) andin a detonation tube. The influence of droplet sizes, concentration of nitrate ester-based fuels, and the fuel quality (i.e., fraction of fuel in vapor phase) on detonation characteristics will be quantified. My expectation is that successfully achieving the overall goal can drastically reduce the cost and time required to implement RDEs in practical systems. These expectations are based on the anticipated discoveries being used to guide the design and testing of RDEs. In the absence of such information, engineers must reply on intuition, trial and error, or poorly established modeling tools,in particular for nitrate ester-based fuels. The proposed research is motivated by the potential for RDEs to be used to drastically reduce the length of combustors and, by extension, the weight of engines. These advances can increase the range of propulsion systems or allow other materials to be carried on the system (e.g., weapons). Unfortunately, the performance of detonation devices burning liquid fuels is only marginally understood. The proposed effort is expected to benefit the warfighter by 1) helping to accelerate development of RDEs for practical systems 2) establish that nitrate ester-based fuels (which the Navy produces and has control over) are advantage for detonation systems, 3) reduce the cost of development and evaluation. Two specific objectives will be accomplished and used to satisfy the overall goal.Objective 1: Develop and evaluate existing and new nitrate ester-jet fuel blends for detonative propulsion applications.Objective 2: Evaluate detonation cell sizes and velocities to understand benefits and disadvantages of using a more readily detonable fuel blend than conventional jet fuel (JP-5).An RDE with an optically accessible linear section will be used to study the influence of nitrate ester-based fuels on detonation behavior. The linear section represents an #unwrapped# RDE. Hydrogen and liquid hydrocarbon fuels will be injected with air into the linear section. The hydrogen/liquid ratio and droplet characteristics will be systematically varied and the influence on detonation behavior quantified. High speed infrared images and pressure transducers will be used evaluate detonation behavior.Detonation cell sizes of the fuel/air mixtures will be measured in a detonation tube with optical access. The detonation frontwill pass the window section and detonation behavior will be quantified. Cell sizes will be measured using soot foils. Ion probeswill be used to measure wave speeds. These measurements will be used to correlate cell sizes to the behavior observed in the linear detonation channel. The most impactful scientific advances expected from the proposed effort include the following:1) The qualityof nitrate ester-based fuels (i.e., fraction of fuel in vapor phase) required for detonations to propagate will be measured in air. 2) Sensitivities of detonation speeds, behavior, and cell sizes to droplet sizes will be measured for varying concentrations of nitrate ester fuels.3) Correlations between detonation behavior and cell sizes will be evaluated. Teleconferences, including slides and videos summarizing key discoveries, will be shared with shared with researchers from NSWC Indian Head. Similarly, and as approved, results will be shared with engineers from OEMs. [Approved for Public Release]
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Nov 09, 2024
- Source ID
- N000142412728
Entities
People
- David Blunck
Organizations
- Office of Naval Research
- Oregon State University
- United States Navy