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System Definition Review. presented by:. XG International. Gihun Bae - Joe Blake - Jung Hoon Choi - Jack Geerer - Jean Gong - Daniel Kim - Mike McCarthy - Nick Oschman - Bryce Petersen - Lawrence Raoux - Hwan Song. Outline of Contents. Mission Statement
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System Definition Review presented by: • XG International GihunBae - Joe Blake - Jung HoonChoi - Jack Geerer - Jean Gong - Daniel Kim - Mike McCarthy - Nick Oschman - Bryce Petersen - Lawrence Raoux - Hwan Song
Outline of Contents • Mission Statement • Market / Customer Verification • Competitors • Concept of Operations • System Design Requirements • Advanced Technologies • Sizing Code • Summary / Next Steps
Mission Statement Develop an environmentally-sensitive aircraft which will provide our customers with a 21st-century transportation system that combines speed, comfort, and convenience while meeting NASA’s N+2 criteria.
Design Requirements • Noise (dB) • 42 dB decrease in noise • NOx Emissions • 75% reduction in emissions • Aircraft Fuel Burn • 40% lower TSFC • Airport Field Length • 50% shorter distance to takeoff **Values for NASA N+2 protocol are found in the Opportunity Statement** NASA ‘s Subsonic Fixed Wing Project Requirements.
Aircraft Concept Selection • Six Initial Concepts and a Datum • Pugh’s Method • Two Result Concepts
Pugh’s Method • Started off by choosing criteria using original QFD: • Fuel Efficiency, Airport Flexibility, Noise, Speed, Range, Attractiveness, Green Image, Personal Space, Passenger Capacity, Smooth Ride (i.e. Overall Vibration) • Gathered concepts and chose a datum concept, the Gulfstream G250, then formed a matrix comparing everyone’s concepts with the datum concept. • Ran with +’s, left out –’s and reiterated a couple of times; feasibility a key issue here. • Took winning ideas, and either added or replaced them on datum concept. • Produced two, ranked “Winning Concepts”
Concept Design 1 Winglet Solar film Duct Turboprop Turbofan
Concept 1 Cont’d 3 Engines 1 Turbofan, 2 Turboprop Conventional Tail Swept back + winglets Battery powered avionics Integrated all-weather solar films NOX-reducing Catalytic Reduction “Green Image” Active Vibration Control System Closeable duct – reduce unnecessary drag from resting engine during cruise • Cons • Heavier • Shorter range • Longer take-off Distance • Slower • Pros • Less expensive development costs • Location of engines doesn’t create moment about c.g.
Concept Design 2 Duct UDF Solar film T-Tail Canard Turbofan
Concept 2 Cont’d 2 Vertically oriented engines 1 UDF, 1 Turbofan T-tail Canard - reduce drag, wing size - create moment about c.g. Battery powered avionics Integrated all-weather solar films NOX-reducing Catalytic Reduction “Green Image” Active Vibration Control System Closeable duct • Cons • Louder • Harder to control • Higher development costs • Pros • Lighter • Faster
Closeable Duct Diverted Airflow diagram Passing Flow diagram
Advanced Technology • Engine-Isolated Internal Power System • Solar Film • Lithium-ion Batteries • Active Vibration Control System • Selective Catalytic Reduction • Un-ducted Fan
Advanced Technology Cont’d • Internal Power : Lithium-Ion Batteries • Replace one APU as power generator for avionics, air-conditioning, pressurization, lighting, electronics • Equivalent APU weight will provide 5kWh of power • Can be charged directly by solar film or ground power source • Backup APU used to start engines, for nighttime operation, as failsafe
Advanced Technology – Solar Film • Copper Indium Gallium Selenide thin film • Demonstrated at 19% efficiency • Can be mounted on plastic, glass, • or metal substrate • All-weather application • Typical performance: >10 W/ft2 • 7.5 hour optimal day-time • operation • Added Weight: 200 lb • Negligible effect on c.g. http://www.ascentsolar.com/site/epage/87631_870.htm
Advanced TechnologyActive Vibration Control • Generates destructive interference • Significantly dampens vibration and noise throughout cabin • Lightweight • 10:1 mechanical advantage • Tunable response • Reduce overall vibration or eliminate completely in specific section of the aircraft
Advanced TechnologySelective Catalytic Reduction • Simple chemical process to remove NOX from exhaust gases • Primary reaction: NO + NO2 + 2NH3 → 2N2 + 3H2O • Pertinent issues: • Catalyst delivery/storage • Removing excess from mix • Optimal temperature range
Advanced Technology Vortex Generators Small vanes or bumps that create turbulence in flow over the wing. Reduces pressure drag by delaying flow separation. Also increases the maximum takeoff weight. Implementation Pros Extremely Light Implementation Cons Difficult to manufacture – increase in cost Placement limited – possibly affect location of solar films
Major Performance Constraint Change from the last constraint diagram Aspect Ratio Mach Number Altitude Service Ceiling Height Major Constraints Landing ground roll Take-off ground roll (for smaller airport compatibility)
Concept 2 Constraint Diagram Concept 1 TSL/WO = 0.36 WO/S = 92.6 lb/ft2 TSL/WO = 0.35 WO/S = 88.3 lb/ft2
Sizing Code Used Excel Spreadsheet 6 Different Sections Main Fuselage Wing Engine Geometry Constraint Diagram Weight Airfoil Mission Detail
Validation Bench Mark : Bombardier Challenger 300 Bombardier Challenger 300 Specification (XG Endeavour) • Range : 3560 nmi (3700 nmi) • Passenger number: 9 (9) • Crew Number : 2 (2) • Cruise Mach Number : 0.8 (0.8) • Service Ceiling : 45000 ft (45000 ft)
Validation Cont’d Features that affect the weight based on the sizing code • High Correlation • Specific Fuel Consumption • Ultimate Load Factor • Low Correlation • Aspect Ratio • Area of the wings • Others
Validation Cont’d Weights based on the sizing code Empty Weight = 17500lb Fuel Weight = 14000lb Total Weight = 34400lb Actual Weights of Bombardier Challenger 300 Empty Weight = 18500b Fuel Weight = 14100lb Total Weight = 35400lb Fudge Factor
Current Approach Current Status Able to predict the weight based on 100+ inputs Empty Weight based on the 22 features of aircraft Empty Weight fraction based on the equation from Raymer’s Fuel Weight fraction based on the weight fractions Future Work Drag calculation based on the altitude Noise calculation
Engine Modeling • Design concepts require two types of engines to be utilized in the final design. • Estimated total thrust requirement = 11,500 lbf. • Turbofan, Turboprop, and UDF engines are among the considerations. • Engines will be modeled based on existing platforms. • The design concepts intend to combine the use of two types of engines, so the effects of separate and simultaneous use will need to be determined.
Turbofan • PROS • CONS • Efficient at subsonic speeds • Lower TSFC • Low direct operating cost • Commercially acceptable technical risk • Relative mechanical simplicity • Proven technology Weight, drag of large diameter fan and nacelle
Turboprop • PROS • CONS • Efficient at cruising altitude, can be more efficient than turbofan • High potential for fuel savings Speed limited to M < 0.65 High noise and vibration
UDF • PROS • CONS • High potential for fuel savings Speed limited to M < 0.85 High noise and vibration Only a few existing designs
Engine Modeling - Turbofan • Baseline engine is HF120 Turbofan • Manufactured by GE Honda Aero Engines • Environmentally Friendly: • Designed to reduce NOx, CO, HC, and smoke emissions. • Meets Stage 4 noise level requirements with room to spare.
Engine Modeling - Turboprop • Baseline engine is the Rolls-Royce M250-B17. • Combines small size and a high power to weight ratio.
Turboprop Cont’d • Specifications:
Engine Modeling - UDF A few concepts have been built in the past, including: GE-36, P&W-578DX, and the Russian built Progress-D27. GE-36 Progress-D27
UDF Cont’d • Very little data exists for the unducted fan engines. • The 3 examples of unducted fans shown were meant for much higher thrust outputs than a business jet requires. • Currently working on an accurate method for predicting performance and scaling to fit the business jet design.
Modeling of Baseline Engines • The three engines shown are the baseline engines that will be scaled to meet the final design’s needs. • The engines will be scaled for proper thrust and fuel flow, while incorporating technology factors to predict performance in 2020.
Technology Factor • According to historical data, seat miles per gallon increased from 26.2 to 49 for small commercial aircraft between 1970-1989. • Improving seat miles per gallon would require the improvement of many individual technologies, and therefore is a good estimate of the overall technological advancement rate. • Seat miles per gallon improved by 3.3 %/yr between 1970-1989. • To be conservative, our design will be based on an assumed overall technological improvement rate of 2 %/yr.
Center of Gravity, Stability, Control Estimates **c.g. travel diagram is not yet calculated
Tail Sizing • Current approach • Design tail so that the a.c. is close to c.g. • More calculation needs to be done • Current estimated size