developments in liquid rocket engine technology · developments in liquid rocket engine technology...
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Developments in Liquid Rocket Engine Technology
Dr. Richard CohnChief, Liquid Rocket Engines Branch
Propulsion Directorate
Air Force Research [email protected]
661-275-5198
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Air Force Materiel Command
MISSION
Deliver war-winning ...
- Technology
- Acquisition
- Test
- Sustainment
... expeditionary capabilities to the warfighter
Air Force Research Laboratory
Mission: Leading the discovery,
development and integration of
affordable warfighting
technologies for America's
aerospace forces.
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AFRL People & Facilities
• 5,400 Gov’t Employees
• 3,800 On-site Contractors
• 10 Major R&D sites across US
• 40 Locations around the World
• 10 Technical Directorates• Air Vehicles (RB)
• Directed Energy (RD)
• Human Effectiveness (RH) (711 HP Wing)
• Information (RI)
• Space Vehicles (RV)
• Munitions (RW)
• Materials & Manufacturing (RX)
• Sensors (RY)
• Propulsion (RZ)
• AF Office of Scientific Research (AFOSR)Distribution A – Approved for Public Release. Distribution Unlimited. PA Clearance #10439
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Space and Missile R&D Building Block Process
6.1 6.2 6.3
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AFRL Propulsion Directorate
Corporate
InformationContracts
Turbine Engine
Division
Engine
Components
Gas Generators
Engine Demos
IHPTET Mgt
Energy, Power &
Thermal Division
Aircraft & Missile Power
Special Power
Thermal Management
Plasma Research
Space & Missile
Propulsion Division
Aerophysics
Analysis
Engines
Materials
Motors
Operations
Propellants
Spacecraft
Aerospace
Propulsion Office
Initiates, Plans,
Promotes and
Conducts R&D
Programs in Adv
Engine Science &
Technology
FinanceCorporate
Development
Integration &
Operations Division
Administration
Civilian Personnel
Computer Support
Facility Support
Front Office Support
As of: 25 Jun 10
WPAFBEdwards AFB
DIRECTORMr. Doug Bowers
Associate DirectorEdwards Site CC
Col(S) Mike Platt
Chief Scientist Dr. Dick River
Deputy DirectorCol Bill Hack
Mr. Dave BlasiusMr. Phil MitchellMs. Cheryl SkipperMs. Mary Donohue-Perry
Mr. John FedonMr. Bill Koop
Mr. Tom Jackson
Dr. Rick Fingers
Mr. Mike Huggins
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―RZ-West‖ Organization
INTEGRATION & OPS
DIVISION (WEST)
MR. K. VANDERDHYDE
RZO (Deputy)
FINANCE
BRANCH (WEST)
MS. RUTH DECOY
RZFB
BUSINESS
OPERATIONS
CAPT MATT
PASTEWAIT/TJ
TURNER
RZOF
INFORMATION
TECHNOLOGY
MR. CARL OUSLEY
RZOI
CHIEF OF SAFETY
MS. DEB FULLER
SE
QUALITY
ASSURANCE
TSGT TIMOTHY
ROWE
QA
EXECUTIVE
OFFICER
1ST LT ERIC MILLER
CCE
FIRST SERGEANT
TSGT CARLOS
LABRADOR
CCF (Add’l Duty)
SPACE & MISSILE
PROPULSION DIVISION
MR. MIKE HUGGINS
AEROPHYSICS
DR. INGRID WYSONG
RZSA
MOTORS
CAPT KRISTEN CLARK
ENGINES
DR. RICHARD COHN
MATERIALS APPS
MAJ(S) A. DUGAS
RZSM
PROPELLANTS
DR. STEVEN SVEDJA
RZSP
SPACECRAFT
DR. JAMES HAAS
RZSS
EXPERIMENTAL DEMO
MS. JULIE CARLILE
RZSO
PAYOFF STUDIES
MR. ROY HILTON
RZST
CONTRACTS
MS. LUCY CASTEL
AFFTC/PK
ASSOC DIRECTOR
SITE COMMANDER
COL(S) MIKE PLATT
RZ
RZSRZ
DET 7
RZ (Edwards)Det 7 Other
RZSB
RZSE
As of: 1 Jun 09
Propulsion Directorate
Mr. DOUG BOWERS
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RZ-West People
Civil Service
(175)
Military
(65)
On-site
Contractors
(240)
Overall
Advanced Degrees
13% PhD
11% MS
Approx. 475 on-site personnel
RZSE
Advanced Degrees
27% PhD
36% MS
5 in Student Programs
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Edwards AFB
Edwards AFB is located about 120 miles North of LAXMap from Google Maps
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MOJAVE
BORONHWY 58
LANCASTER
AVENUE E
HIG
HW
AY
14
LA
NC
AS
TE
R B
LV
D.
14
0th
ST
RE
ET
EA
ST
RESERVATION BOUNDARY
0 5 10
SCALE IN MILES
HWY 395
ROSAMOND BLVD.
MERCURY BLVD.
RO
CK
ET
SIT
E R
OA
D
EDWARDS AIR FORCE BASE Air Force
Research
Laboratory
Site
ROGERS
DRY LAKE
ROSAMOND
DRY LAKE
AFFTC
Edwards AFB
HWY 58
D.C.
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High Thrust Facilities
NINETEEN LIQUID ENGINE
STANDS TO 8,000,000 LBS THRUST
THIRTEEN SOLID ROCKET MOTOR
PADS TO 10,000,000 LBS THRUST
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Facilities: Bench-Scale Labs
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History
• 1939 – Rocket research begins at Power Plant Lab, Wright Field OH
• 1947 – Edwards AFB selected for rocket testing
• 1959 – Rocket scientists move from WPAFB to Edwards
• 1997 – AF labs consolidated into AFRL
• Key Accomplishments
– Saturn V F-1 engine development
– Minuteman ICBM silo basing
– XLR-129 engine (for Shuttle main engine)
– Peacekeeper ICBM development
– Missile defense interceptor HOVER tests
– Titan IV solid rocket motor upgrade
– RS-68 engine for Delta IV EELV
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AIAA’s 1st Historical Aerospace Sites (2000)
1. Rocket Site
2. Aerojet Pasadena, CA
3. Goddard First Auburn, MA
4. Dutch Flats San Diego, CA
5. Tranquility Base
6. Huffman Prairie, OH and Kitty Hawk, NC
―Helped to Advance the Arts, sciences
and technology of aeronautics and
astronautics, and promoted the
professionalism of those engaged in
these pursuits.‖ -AIAA
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AFRL Edwards Rocket Site: LiquidRocket Technology Development
Air Force Programs
Air Force Proposed
Other Programs
X-33
XRS-2200
On-Demand Launch
(RBS)
Space Vector 1
AFRL Aerospike Tech
AFRL Thrust
Cell Program
Military Space
Plane & SOV
AFRL IPD
Concept
Engine
AFRL XLR-129
Space
Shuttle
SSME
X-15
AFRL XLR-99
RL-10
Centaur Upper Stage
CL-400 Suntan
DC-X
J2X
RS 68- A/B ARES
Four Decades of Leadership in Rocket Engine Technology
AFRL HCB
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Key Rocket Parameters
• Key components of rocket engines– Main Thrust Chamber – Most catastrophic failures
– Preburner/Gas Generator – Most tech challenges, harshest environment
– Turbopump – Most likely to delay development, increase costs
• Booster Engines– Booster stages provide initial thrust to lift vehicles off the launch pad
– Booster engines require high thrust
– Flow-rates can exceed 1000 lbs/s of propellant
• F-1 engine flow-rate ~650 gal/s 1.5 Swimming Pools/minute
• Upper Stages– Final thrust to transfer orbit
– Moderate thrust, high performance requirements
• Critical parameters for rockets include– Specific Impulse
– Thrust to weight
– Throttle
– Operability
– Reusability
– ReliabilityDistribution A – Approved for Public Release. Distribution Unlimited. PA Clearance #10439
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Differences between Rocket & Jet Engine
• Rockets use pure oxygen as oxidizer
– Operate at significantly hotter combustion temperatures
– Pumps need to operate at cryogenic conditions
– Oxygen Blanching
– Oxygen ignition of materials
• Rockets may use liquid hydrogen as a fuel
– Extreme cryogenic conditions
– Hydrogen embrittlement
• Potentially very high pressures
– Can exceed 6000+ psi in some components
• Extremely high heat fluxes
• Operate at 100% throttle during most of mission
– Total operational time measured in minutesDistribution A – Approved for Public Release. Distribution Unlimited. PA Clearance #10439
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Comparison of Rocket and Turbojet
500,000 lbf 50,000 lbf
Power density 10X greater in rocket compared to turbojet
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Liquid Engine Branch Current Objectives
• Technology focused
• Develop the technologies needed to develop next generation of flight liquid rocket engines
– Do not develop a solution to a particular point design but attempt to increase design space
– Do develop integrated technology demonstrator engines
– Tools are a critical part of that mission
• Systems engineering approach
– Both in execution and selection of technology to develop
• Current focus
– Reusable Boost Stage
– Expendable Upper Stage
• Future focus
– Reusable upper stage
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Joint government and industry effort focused on developing
affordable technologies for revolutionary, reusable and/or rapid
response military global reach capability, sustainable strategic
missiles, long life or increased maneuverability spacecraft
capability and high performance tactical missile capability
SMV/SOV
Air-to-Air Missiles
High Energy
Upper Stages
ELVs ICBMs
SLBMs Satellites
Micro-Satellites
Integrated High Payoff Rocket Propulsion Technology (IHPRPT)
Ground/Surface
Launched Missiles
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Liquid Rocket Engine Technology Efforts
• Rocket Engine Technology Demonstration Programs
1. IPD (Lox/LH2 Booster)
2. USET (Lox/LH2 Upper Stage)
3. Hydrocarbon Boost (Lox/RP-2 Booster)
4. 3GRB (Lox/LCH4 Booster)
• Core Technology Efforts
– Drive towards Modeling and Simulation
• Most common conference to present programs JANNAF
– ITAR restrictions
– It is open to people from academia
– Must be a US citizen
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1. Integrated Powerhead Demo (IPD)
• Joint program between AF, NASA, and Industry
• Supports sortie-like launch for Operationally Responsive Space (ORS)
• Payoffs:
– 200 Mission Life (20X improvement)
– 100 MTBOH
• First known full scale demonstration of Full Flow Staged Combustion Cycle in the World!
IPD Ground Engine: E1 Test Stand NASA SSC, Test
014TA: Standard Start to 85%PL, (Actual 89%PL) w/
Steady State; Test Profile SA, December 15th, 2005
IPD Ground Demonstrator Engine
installed in E1 Complex Cell 1
IPD Ground Engine: E1 Test Stand NASA SSC, Test
013TA: Standard Start to 80%PL, 87%PL w/ Short Hold;
Test Profile RA, November 10th, 2005
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IPD Program
• IPD program sought to improve the nations technological capability in Liquid Hydrogen/Liquid Oxygen (LH2/LOX) booster engines
• Design began by examining the failure modes of the SSME
• Sought to eliminate these failures through the use of a new engine cycle
– Full Flow Staged Combustion
• Program executed by team consisting of:
– AFRL
– NASA
– Rocketdyne (now Pratt & Whitney Rocketdyne)
– Aerojet
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• Benefits Provided
• Reduced Turbine temperatures
• Improve turbine life and increases reliability
• Eliminates of two criticality 1 failure modes
• Turbopump interpropellent seal
• Heat exchanger to pressurize propellant tanks.
• Thermally gentle start sequence
• increases turbine life
• Current SOA
• High Pressure LOX/LH2
• Booster
• Space Shuttle Main Engine
• Fuel Rich Staged Combustion
Benefits of IPD Full Flow Cycle
• Successful Test Program with one set of hardware
• Incorporation of large amounts of Modeling and Simulation tools
• Tools drive the test process
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2. Upper Stage Engine Technology (USET)
• RL-10 Engine initially developed in the 1950’s and first flew in 1961
• RL-10 engine is currently used on both EELV
• AFRL USET program seeks to allow the creation and transition of a modern upper stage engine
– Focus on developing critical tools
• Two contractor teams
– Aerojet
– Northrop Grumman
All
operational
DoD
satellites
lifted by
EELV
Atlas V
Upper stage
RL10-A-4-2
Delta IV
Upper
stage
RL10-B-2
Turbopump
Assembly
Identify Issues
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USET Objective
• Objective: Develop and demonstrate the next generation Model Driven Design (MDD) tools on an upper stage engine component
– Selected Turbopump
• Approach:
– Link commercial design tools with rocket specific empirical data, rocket specific material & propellant libraries, and user defined functions
– Replace targeted legacy design tools with physics based tools
• Enable Multi-Disciplinary Models, Time Accurate Solutions & Interconnected Models
– Reduced design time, more design iterations
– Higher fidelity analysis earlier in process
– Multi-disciplinary optimization
– Use Tools to design validation turbopump assembly
• Validation: provide sealed envelope predictions to compare with test data
Models & design tools applicable to other Liquid Boost & OTV Applications
- Range of Thrust - Range of Propellants - Range of Engine Cycles
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USET Output
Validation Turbopump
System Tool
Thrust Chamber Tools
Turbopump Tools
Modeling & Simulation
USET
Tools
– Pump and Inductor Performance
– Cavitation
– Integrated Vibration Tool
– Bearings
– Turbine Performance
– Axial Thrust Critical Fits Clearances
– Transient
– Engine Start Margin
– Linked Coolant Combustion
– System Sizing Tool
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USET Validation Turbopump
Challenges
• Design and Fabrication of
Highly Instrumented Pump
– Over 100 measurements
– Full shaft position
measurement system
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USET AccomplishmentsAFRL Test Stand - Facility Readiness Review (FRR)
• Activation with GN2 and LN2 Complete
• Hydrogen Vents, Drains, and Flarestacksystem upgraded to comply with recent changes in NFPA code
• Successfully passed Facility Readiness Review (FRR)– Facility permitted to load Hydrogen
– First LH2 loaded on 2 Feb 10
• Testing to complete in FY2011
Pump Supply Line
Test Stand 2A Activation
USET Validation TPA
inside of Test Skid
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USET Tool Improvement
(Pump Performance Methodology)
Description
• Enables 3-D Pump Component Design
& Performance Analysis Early in
Development
• CFD Based Verification of Pump
Efficiency, Head Coefficient, and
Cavitation
• Current Methodology
– Meanline Empirical Design
– Limited CFD Late in Design
Process
Impact
• Better Performance Verification Earlier in
Design Process (Fidelity Forward)
– Enabled USET Cavitation
Optimization
– Enabled Improvement of Off-Design
USET Performance
• Lower Test Risk
• Reduced Design Iteration Late in
Development
USET Improvement
• 3-D CFD Verification of Design
Performance
• CFD Based Optimization
• Cavitation Performance Optimization
• Assessment of Off-Design Stability and
Performance Early in Design Process
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3. Hydrocarbon Boost
Hydrocarbon Boost establishes the required
tech base/knowledge base for domestic ORSC engine
• Developing new Liquid Oxygen/Kerosene staged combustion engine
– 250k skid based brass board demo engine for simplified test stand operations
• 12 year development effort (2007-2019)
– Aerojet Prime contractor
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Hydrocarbon Boosters: State of the Industry
Increased Life + Operability + Performance =
HC Boost Demo Will Redefine Global State-of-the-Art
270
280
290
300
310
320
330
340
350
0 200,000 400,000 600,000 800,000 1,000,00 1,200,00 1,400,00 1,600,00 1,800,00 2,000,0
Thrust (Klbf)
Isp
(V
ac)
MA -5
Atlas I/II
1963
RS -27
Delta II/III
1972
H -1
Saturn I
1961
US Technology Base
Gas Generator Cycle
RD -170
Zenit
1987
F -1
Saturn V
1967
NK -33
N -1
Never Flown Russian Technology Base
Ox -Rich Stage Combustion Cycle
RD -180
Atlas V
1999
200 400 600 800 1000 1200 1400 1600 1800 2000
270
280
290
300
310
320
330
340
350
0 200,000 400,000 600,000 800,000 1,000,00 1,200,00 1,400,00 1,600,00 1,800,00 2,000,0
Thrust (Klbf)
Isp
(V
ac)
Russian Technology Base
Ox-Rich Stage Combustion Cycle
200 400 600 800 1000 1200 1400 1600 1800 2000
US Technology Base
Gas Generator Cycle
RD-170
Zenit
1987
RD-180
Atlas V
1999
RD-191
Naro-1
2009
NK-33
N-1
Never Flown
Merlin 1C (100k)
Falcon (1&9)
2008FS-27
Delta II/III
1972
MA-5
Atlas I/II
1963
H-1
Saturn I
1961
F-1
Saturn V
1967
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Program Objectives
• Develop a 250K-lbf thrust, oxidizer-rich staged combustion cycle LOX/Kerosene Liquid Rocket Engine
• Show scalability of technology up to very large thrust levels
• Develop technology to meet operability objectives
• Baseline fuel is advanced rocket grade kerosene
• Demonstrate goal achievement through testing and analysis
• Isp
• Thrust to Weight
• Failure Rate
• Production Costs
• Throttleability
• Mean Time Between Overhauls
• Mean Time Between Replacement
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Vision
EngineTRL 3
Subscale /
Rig Testing
TRL 4Component
Testing
Integrated Engine
Cycle Testing (250K)
TRL 5
Systems Engineering Approach to Operational HC Engine Development
Component TRL – Green
System TRL – Purple
’’
TRL 6
Flight weight
Engine
TRL 9Prototype Engine
Modeling, Simulation and Analysis
TRL 5
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Subscale Ox-Rich Preburner Assembly
LOX Inlet
Injector
Calorimeter Chamber
Diluent Chamber
L’ Chamber
Instrumentation Ring
Throat
Igniter
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3535
• The objectives of the test are to provide validation data for the tools
used to design the hardware and evaluate the operation of the
hardware.
• For each injector design evaluate:
– Combustion performance via axial energy release distribution
– Combustion stability characteristics
• High-frequency transverse modes
• Chug & longitudinal modes
– Injector face, acoustic cavity, & chamber wall thermal compatibility
– Steady-state temperature uniformity of preburner exhaust gas
– Ignition characteristics
• Start transient characteristics/low-throttle operation
Subscale ORPB Rig Test
Test Objectives
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Structural & Thermal Analysis:
Finite Element Analysis (Commercial)
Combustion device M&S design roadmap
CoDR PDR CDR
CFD Approach (Commercial)
Mixing Flow,
No Chemistry
•Mixing Of Two
Streams
• r=r(Yi,T)
Estimate Heat
Release Profile
•One Step
Chemistry
-r=r(Yi,T)
•pdf, Equilibrium
-r=r(f,f‖)
Refine Heat Release
Profile
•One Step Chemistry
•Multi Steps
Chemistry
•Reduced
Mechanism
Need Test Data To
Guide CFD Model
Refine Chemistry To
Account For RP
Decomposition
•Multi Steps Chemistry
•Droplet Combustion (?)
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Example of CoDR Level CFD Analysis
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4. 3GRB
• Advancement of the state of the art
– Innovative cycles/ component technologies
• Pursue IHPRPT Hydrocarbon Boost Phase III and Operability Goals
• Fuel Choice
– Rocket Grade Methane MIL-PRF-32207 is the baseline fuel
– Methane has high potential as fuel for booster stage rocket engines
– Database and experience on pump fed methane engines is lacking in US
• AFRL to leverage existing pressure fed activities (NASA)
• Develop rocket engine components
– Component and/or breadboard validation in laboratory environment
– No integrated demonstration
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Program Objectives
• Develop component technology for a high performance next generation LOX/LCH4 liquid rocket engine
• Show scalability of technology up to very large thrust levels
• Develop technology to meet operability objectives
• Baseline fuel is advanced rocket grade methane
• Demonstrate goal achievement through testing and analysis
• Isp
• Thrust to Weight
• Failure Rate
• Production Costs
• Throttleability
• Mean Time Between Overhauls
• Mean Time Between Replacement
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3GRB Roadmap
FY 09 FY 10 FY 11 FY 12 FY 13 FY 14 FY 15
Task Order 1Aerojet
Task Order 1Pratt and Whitney
Rocketdyne
Task Order 1WASK
Initial Risk Reduction
Component Demonstration
Vision Engine
Development
Vision Engine
Development
Vision Engine
Development
Initial Risk Reduction
Task Order 2Contractor TBD
Task Order 2Contractor TBD
Task Order 3Contractor TBD
IDIQ competition
Task Order competition
Task Order competition
3 Awards Task Order 1—Complete
Trade studies
Vision engine development
Technology Identification
Risk reduction
Plan 2 Awards Task Order 2 – Initial
Risk Reduction -- In source selection
Mitigate critical risks identified in
TO 0001 through M&S
1 Awards Task Order 3
Further Risk Reduction and ValidationDistribution A – Approved for Public Release. Distribution Unlimited. PA Clearance #10439
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• Staged Combustion Cycle
– Low Preburner Gas Temperature Assures Long Life
• Multiple Thrust Chamber Assemblies
– Small TCAs improve High Frequency Combustion Stability
– Center of Mass Pulled Close to Vehicle Interface
– Small TCAs Lower Development and Test Costs
• Compact TPA
Aerojet Vision Engine Overview
Fuel Inlet
LOX Inlet
OX Isolation
Valve
Preburner
Fuel Cooling Manifolds
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PWR Vision Engine
•Expander-Heat Exchanger Cycle (Ex-Hex)
•HEX reduces system pressures
–Enables higher Pressure Ratio turbine
–Reduces heat required to run cycle
–Significantly reduces Turbopump power
•Ex-Hex Eliminates Preburner
–No moisture / contaminates
–Eliminates drying / flushing
–Significantly reduces Ground-Ops
•Low CH4 Hot Gas Temp
–Reduced hot gas system complexity
–Benign fluid environment
–Improved turbine drive system life
•Lower Engine pressures
–Existing test facility infrastructure
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WASK Vision Engine
• Staged Combustion Cycle
– Low Preburner Gas Temperature Assures Long Life
• Modular engine design
– Small TCAs Lower Development and Test Costs
– Altitude compensating nozzle
• Innovative TPA
– Eliminates boost pumps
– Single shaft
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Drive Towards Model Driven Development
• There is a need to improve 30-40 year old modeling, simulation, & analysis (MS&A) tools
– Existing tools old and empirically based and require hundreds of tests
– Industry losing grey beards and thus design and analysis capability
– Could not handle new technologies like hydrostatic bearings
– Current and future computational capabilities allow use of physics-based tools to supplement testing
– Testing drives the cost of rocket programs
• Necessary
• Need to be smart
Test Driven
Development
(TDD)
Model Driven
Development
(MDD)
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Preburner Research
• In-House projects within RZSE– Research needs identified to support external efforts
• Exploratory
• Gain a more fundamental understanding of design space
• Themis– High pressure hydrocarbon propellants
• LOX-RP, LOX-LCH4
• Staged combustion cycles
• Focus on Ox-Rich Preburner– Highest component risk to Hydrocarbon Boost effort
– Gain understanding of preburner environment
• Lack of basic understanding
• Not an optimization or demonstration of a single design
• Encompassing approach– Not a single experiment or facility
– Both experiments and CFD
– Water visualization, cryogenic cold flow, hot fire testing
– Provides early validation data for Hydrocarbon Boost
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Preburner Research Focus
• Combustion devices are focus
– Preburner is first priority
• Configuration of interest is significantly different than typical rocket hot gas devices
– Combustion device requires good mixing
• High density diluent injection
– Multiple flush ports injecting the fluid
– Simplification of geometry results in JICF configuration
• Jet-In-Crossflow (JICF)
– Available literature is extensive
– Most research has been done at academia
– Understanding at relevant environment and integrated configuration is low
Temperature uniformity
Concentration uniformity
Flow uniformity
Injector Diluent Injection
Low MR
High T
Mixing
Tu
rbin
e
Goal: T uniformity
High MR
“Low” T
•Supercritical Fluid Flows
•Multiple Jets/Jet Systems interaction
•3D configuration constrained
•Extreme Pressure
•High J
•High Rrho
•Reacting flows
•Subsonic Flows
•Penetration
•Vortex Generation
Well Understood, Extensive Literature
Available
Themis Simulations
•Supersonic Flows
(Ramjet/ Scramjet)
•Atomization
•Aeration of Jets
•Residence Time
•Weber Number
Relations
JICF Literature
Not capable of
comparison in
a cold flow
experiment
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Preburner Mixing ProcessesMultiple Confined Transverse Jets
• Understand mixing of LOX with combustion gases– From transverse jet literature
• Importance of entrainment in governing jet trajectory• Scaling laws, confined and unconfined
– Phased research process• Water-visualization facility
– Explore mixing efficiency and scaling laws for relevant geometry
• Low-speed variable gas facility– Employ different gases to achieve relevant density ratio and mass flow
ratio regime
• High-pressure ―cold-flow‖ facility– Liquid N2 injection into He/Ar gas– Supercritical fluid mixing phenomena (dilatation, transport property
variations, etc.)
• ―Hot-fire‖ test facility– Sub-scale preburner configurations– Explore combustion/mixing interactions
– Tools• Experimental: LDV, PLIF, flow visualization, PIV, temperature and pressure
sensors• Computational: CFD and linear stability analysis
Incre
asin
g r
ele
van
ce
Decre
asin
g a
ccess
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High Performance Hydrocarbon Fuels
• Develop and transition new fuels
• Feedback to chemists to improve fuel performance
– Tailor fuel properties
• Density
• Energy
• Vapor Pressure
• Thermal Stability
• Energy density of advanced synthetic fuels offers potential for:
– Use of advanced fuels as additives to improve performance for specialized missions
– Improved performance for volume constrained applications
RP-1
Fuel 1
Fuel 2
Fuel 3
C* RP-1
C* Fuel 1
C* Fuel 2
C* Fuel 3
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Improve Current Fuels
RP-1, Standard
GradeTS-5 RP-2, Advanced
Grade
• Led development of new grade of rocket propellant
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Thermal ManagementTranspiration Cooling
• AFRL in a joint program with Northrop-Grumman and Rolls Royce Liberty Works performed some of the first experiments examining transpiration cooling in a rocket engine environment
• Utilized several Lamilloy™ samples to determine applicability for rocket engine applications
– Lamilloy™ currently in use for turbine applications
– First application in rocket environment
• Seven months from concept initiation to program completion
• Demonstrated feasibility of using Lamilloy™
– Need to design specifically for rocket engine applications
– Within experience base
Sample Lamilloy™ Sheet
Test Section
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Combustion Instabilities
• Combustion Instabilities are a key risk to any rocket engine development program
• Can be extremely destructive and can destroy the engine and the test stand
• Complex interaction between many phenomena
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Materials Research
• Spearheaded development of Mondaloy, a new, high strength, oxygen compatible metal
• Spearheaded development of nano-aluminum which has greater strength than typical aluminum alloys
Bulging
indicates
ductile
failure mode
In both std
and NP Al
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Conclusions
• AFRL/RZS is leading the development of the next generation of rocket engine technology
• Focused efforts examining Cryo-Boost, HC Boost, and Upper Stage Rocket Propulsion
– Aggressive goals lead to unique vision engines
– Tool development is crucial
• Developing the critical demonstration programs as well as the key underlying technologies
• Improving Modeling and Simulation Tools essential for the next stage in rocket engine development
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