RollsRoyce University Technology Center in High Mach Propulsion

Rolls-Royce University Technology Center in High Mach Propulsion – Year 1 Review and Status Update S. Heister, W. Anderson School of Aeronautics & Astronautics I. Mudawar, P. Sojka School of Mechanical Engineering Rolls-Royce High Mach Propulsion UTC

Outline 1. UTC Overview & Year 1 Goals – Heister 2. Fuel/Air HEX Project Status – Mudawar 3. Supercritical Fuel Injection Project Status – Sojka 4. Afterburner Cooling Project Status – Anderson 5. Summary & Year 2 Plans - Heister Rolls-Royce High Mach Propulsion UTC

Senior UTC Personnel • Dr. Steve Heister, UTC Lead, propulsion, two-phase flows, engine cycles • Dr. Bill Anderson, combustors, fuel stability • Dr. Issam Mudawar, high heat-flux heat transfer • Dr. Paul Sojka, supercritical “atomizer” design & spray characterization • Dr. Jay Gore, IR spectroscopy • Mr. Scott Meyer, Senior Engineer, facilities & instrumentation • Ms. Melanie Thom (Baere Aerospace Consulting): over 15 years experience in fuel systems Rolls-Royce High Mach Propulsion UTC

Collaborators & Students in UTC • Fuel/air HEX project – – Mr. John Tsohas, M. S. student Mr. Neal Herring, Ph. D. student Mr. Tim Kibbey, M. S. student and Rolls-Royce Fellowship recipient Mr. Adam Finney, undergraduate student • A/B cooling project: – Mr. Tom Martin, M. S. student and Ross Fellowship recipient – Mr. Eric Briggs, M. S. student • Supercritical fuel injection project: – Mr. Greg Zeaton, M. S. student – Mr. Omar Morales, MARC/AIM program Rolls-Royce High Mach Propulsion UTC

High Mach Propulsion UTC 5 Year Plan Two-phase Fuel Injection Design injector(s) for two-phase fuel mixture flow into combustor • Test at least two injector designs to develop data base for mass-driven spray formation • Develop design models to treat mass-transfer driven spray formation • Predict mean drop size and drop size distribution in terms of atomizer operating conditions, nozzle geometry, and fuel physical properties • Build on existing effervescent atomizer model development • Include influence of fuel vaporization/cracking, which can produce liquid/vapor mixture • Develop design models to treat mass-transfer driven spray evolution • Predict patternation, cone angle, entrainment of surrounding air, and penetration • Build on existing effervescent atomizer model development (effervescent Diesel injection) • Eventually include vapor distribution as well as liquid distribution Rolls-Royce High Mach Propulsion UTC

3. Supercritical Fuel (SCF) Injection Project Status Rolls-Royce High Mach Propulsion UTC

Supercritical Fluid (SCF) Injection Experiment Goal Ø Identify performance limitations for SCF injection and develop design guidelines for future high-Mach engines Ø A literature review of previous supercritical fluid injection studies suggests fuel superheat, atomizer geometry, and gas/fluid density ratio are the key variables that effect Ø “Spray” cone angle Ø Patternation Ø “Spray” momentum rate distribution Rolls-Royce High Mach Propulsion UTC

SCF Injection – Fluid Selection Ø Jet fuel ruled out for initial experiments Ø HOQ is engineering approach to decision making Ø Surrogate “fuel” selected based on human factors and functional performance Rolls-Royce High Mach Propulsion UTC

SCF Injection – Fluid Selection Ø CO 2 selected as surrogate “fuel” for first experiments Ø Relatively safe, inert, non-toxic Ø Inexpensive, readily available Ø Supercritical thermodynamic and transport properties are already well defined Ø Non-combustible so no need to redesign existing spray apparatus Ø Tc “low” so existing apparatus can be used Rolls-Royce High Mach Propulsion UTC

Baseline Injector and Preliminary Results Rolls-Royce High Mach Propulsion UTC

SCF Injection – Baseline Pressure Swirl Injector Ø Pressure swirl atomizer selected as baseline configuration for evaluation Ø Larger cone angles (better distribution of fuel mass in the combustion chamber) than demonstrated in previous experiments using plain orifice injectors with SCF’s Ø Injector geometry is easily modified to obtain desired spray characteristics Rolls-Royce High Mach Propulsion UTC

SCF Injection- Baseline Pressure Swirl Injector Design Rolls-Royce High Mach Propulsion UTC

SCF Injection - Preliminary flow visualizations Ø H 2 O-in-air (1) and H 2 O-in-H 2 O (2) flows demonstrate the influence of density ratio on spray evolution Ø A density ratio similar to H 2 O-in-H 2 O (near unity) will be present when SCF experiments are performed (1) 9. 2 g/s (2) Rolls-Royce High Mach Propulsion UTC 9. 2 g/s

SCF Injection - Preliminary flow visualization Ø An overall decrease in cone angle with increased density ratio was observed Rolls-Royce High Mach Propulsion UTC

SCF Injection - Experimental apparatus Ø Ø Test vessel CO 2 supply system Air supply system DAQ system Rolls-Royce High Mach Propulsion UTC

SCF Injection – Test vessel Injector Windowed chamber Ø Originally used for Diesel injection Ø Recently upgraded to withstand pressures of 1500 psi (10. 3 MPa) Ø Reconfigured for supercritical CO 2 operation (O-rings, supply lines, etc. ) Rolls-Royce High Mach Propulsion UTC

SCF Injection – CO 2 supply system Rolls-Royce High Mach Propulsion UTC

SCF Injection – Co-flow air supply system Rolls-Royce High Mach Propulsion UTC

SCF Injection - Test rig CO 2 heater PID heater controls Air heater Test vessel Metering valve Optical table Gas booster Rolls-Royce High Mach Propulsion UTC

SCF Injection – Test rig Dome regulator Co-flow air manifold Coriolis flow meter Test vessel TC probe Rolls-Royce High Mach Propulsion UTC

SCF Injection - DAQ & control SCXI interface Control output panel Analog input panel TC panel Rolls-Royce High Mach Propulsion UTC

SCF DAQ – optical patternator Ø Optical patternator developed at Purdue Rolls-Royce High Mach Propulsion UTC

SCF DAQ – Momentum rate probe Ø Technique refined at Purdue over the last ten years Ø Characterizes spray penetration via force balance Ø To be installed in test vessel Rolls-Royce High Mach Propulsion UTC

SCF Injection – Overview of system capabilities Ø Heat and pressurize CO 2 above its critical T and p and inject into ambient environment whose p and T exceed critical CO 2 values Ø Operate at any combination of p and T above CO 2 critical values Ø Obtain shadowgraphs of spray cone angle Ø Uncertainty: +/-5 % Ø Obtain mass distribution data Ø Uncertainty: +/-0. 5% Ø Obtain momentum rate data for spray penetration Ø Uncertainty: +/-1% Rolls-Royce High Mach Propulsion UTC

SCF Injection – Status Ø Facilities near completion Ø waiting on accumulator (to damp injection pressure pulsations) Ø TRR next week Ø DAQ software optimization Ø Configure optics Ø SCF experiments will begin by the end of January 2004 Rolls-Royce High Mach Propulsion UTC

Gearing Status • Leveraging of UTC funds is a primary goal • Current Status – NASA MSFC “Risk Reduction for the ORSC Cycle” • ~ $0. 5 M w/ ~ 1/3 focused on thermal management – NASA GRC “Flow Boiling Critical Heat Flux in Reduced Gravity” (~$0. 5 M) – RR/AADC Industrial Affiliates Fellowship for Tim Kibbey – Purdue Ross Fellowship for Tom Martin – U/G Honors thesis project Adam Finney – MARC/AIM summer fellowship for Omar Morales – AFOSR MURI in Hypersonic Transition Rolls-Royce High Mach Propulsion UTC

Summary – High Mach UTC • Schedule on track to fulfill Year 1 goals – Research team in place – Fuel Thermal Management Lab nearly complete – Facility mods to spray diagnostics lab nearly complete • Gearing/leveraging efforts already successful, future efforts to explore projects with AFRL and/or NASA GRC Rolls-Royce High Mach Propulsion UTC