Hydrogen Business Jet Preliminary Design Review Team III

1
Hydrogen Business JetPreliminary Design
ReviewTeam III

• Derek Dalton
• Megan DarraughSara DaViaBeau GlimSeth
  HahnLauren NordstromMark Weaver

2
Design Requirements

• Alternative fuel lH2
• Mid-sized
• 8 passengers
• Ultra-long-range business jet
• Providing non-stop service between locations such
  as Los Angeles-Tokyo

Range 5,700nmi
Passengers 8
Cruise Speed 0.80M
3
Market Overview

• Projected 10-year revenue is 50B for the entire
  ultra long range market
• Acquire 15 market share within 10 years
• Approximately 20 aircraft sold annually
• 1.2B in potential annual sales, 2 of total
  business aviation market
• Expect to enter market in 2040
• Assuming 12B in development costs, will break
  even in 10 years

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Hydrogen Business Jet
5
Front View
28 ft
8 ft
83.5 ft
6
Side View
26.45 ft
12 ft
123 ft
7
Compliance with Requirements
  Required Design
GTOW (lbs) 70,000 58,700
Vcruise (KTAS) ³460 460
Hcruise (ft) ³40,000 40,000
Range (nmi) ³5,700 5,700
Landing Field Length (ft) 5,600 5,370
Thrust per Engine (lbs) 15,000 12,630
Fuel Weight 11,700 11,600
Cruise Altitude Rated
8
Carpet Plots
Design Point
L/D and Fuel Weight are constraining parameters L/D and Fuel Weight are constraining parameters
GTOW 58,700 lb
AR 11.9
T/W 0.43
W/S 100 lbs/ft2
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Carpet Plots
Design Point
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Flight Envelope
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V-N Diagram
Load Factors Load Factors
Vstall 117 kts (SL)
Altitude 28,000 ft
Nlim 3.2g
Nult 4.8g
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Mission Performance
  Distance (nm) Time (mn) Fuel (lbs) Speed (Mach) Altitude (ft) Altitude (ft) Thrust (lbs) Thrust (lbs) L/D
          Start End Start End  
Taxi Out -  10 43  0 0 0  - -  - 
Take Off - 0.4 22 0  0  0  0 18,091 16
Climb 252.4 36.3 767 0.3 0 37,686 18,841 3,822 16.5
Cruise 5501.4 719.4 9552 0.8 37,686 40,000 3,822 3180  14.6
Hold   39.1 488  - -  - - - -
Descend 127.1 27.1 143 0.3 40,000 0  - - 17
Taxi In -  10 43  - 0 0 - - -
Reserves -   - 1052 -  -   -  - -  - 
Flight Total 5880.9 782.8 12126  - - - - - -
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Twin Spool Turbofan

• Unmixed flow
• Bypass ratio 4.5
• Total pressure ratio 25
• Weight 4,400 lbm
• Diameter 3.6 ft
• Thrust (SLS) 33,800 lbf
• SFC (SLS) 0.14 lbm/lbf-hr

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Fan Study at SLS
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Structures Materials

• Wing fuselage skin Carbon Epoxy laminate
• Core in laminate adds stiffness for little
  additional weight
• The laminate can be compared to an I-beam
• Skins act as the I-beam flange
• Core materials act as the beams shear web
• Pylons Titanium (Ti 6Al- 4V)
• Good for high load, poor shear properties

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Structures Materials

• Ribs/stringers
• Al 2024
• Al 7075
• Al-Li alloy in future
• Landing gear
• Steel 300M
• Spar
• Aluminum 7175T66 will be used to get a 1.7 safety
  factor

Engine Weight
Wing Weight
Fuselage
11.5 ft
16.9 ft
Lift Force
21.5 ft

• Lift was simplified to a point load at the
  aerodynamic center since the specific airfoil was
  not chosen

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Landing Gear

• Tricycle configuration
• Better visibility, good maneuverability
• Requires proper balance to ensure braking and
  steering effectiveness
• Oleo-pneumatic shocks

Diameter Rear Tire 29.2 in Width Rear Tire 9.2 in
Diameter Front Tire 20 in Width Front Tire 6.6 in
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Supercritical Airfoils

• Relatively high cruise speed cause local shocks
  on most airfoils
• Supercritical airfoils reduce the severity of the
  shocks by distributing the pressure over the
  entire chord

19
Airfoil Selection

• Unable to choose an airfoil because of limited
  data available on specific supercritical airfoils
• Most aircraft with transonic cruise have airfoils
  tailored to their specific mission

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Weight Breakdown
Wing 5,200 lb
Fuselage 18,260 lb
Landing Gear 2,545 lb
Structure Total 27,000 lb
Engines 4,380 lb (x2)
Fuel 11,600 lb
Systems Equipment 10,160 lb
Empty Weight 43,570 lb
Payload 2,730 lb
GTOW 58,700 lb
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Weight Location
123 ft
X
61.6 ft
Wfuel 2,3,4 A
Wfuel 2,3,4 C
Wfuel 2,3,4 B
Wbaggage
Wwing
Wcrew
Wfuel 1
Wlanding gear, front
Wengine
Wfuselage
Wverticle tail
Whorizontal tail
Neutral Point
22
Fuel Storage
2
A
B
C
3,4
12 ft
8 ft
Passengers
Pax Area
1
35 ft
Fuel Weight 11760 lb LH2 Density 4.23 lb/ft3
78 ft

• D 8 ft, L 43 ft, V 2027 ft3 8575 lb LH2
• Each Section D 3 ft, L 25 ft, V 169
  ft3 717 lb LH2
• Tank 2 V 509 ft3 2152 lb LH2
• Each Section D 1.5 ft, L 25 ft, V 41
  ft3 172 lb LH2
• Tank 3 V 122 ft3 516 lb LH2
• Each Section D 1.5 ft, L 25 ft, V 41
  ft3 172 lb LH2
• Tank 4 V 122 ft3 516 lb LH2
• Total V 2780 ft3 11760
  lb LH2

Nose 28 16 ft Tail 3.68 28 ft Total 78
16 24 123 ft
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C.G. Travel
Neutral Point
24
Dynamic Stability
Vertical Tail Volume
1 Engine Out Takeoff 350 ft2
Cross-wind Landing 307 ft2
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Cost

• Acquisition Cost
• Based off Average of FLOPS and Historical Trend
  Data
• Both took into account increased technology as
  weighted factors

• Direct Operating Cost (DOC)
• 5/gallon for Hydrogen
• 4 Flight Crew
• Weighted Factors for Engine/Airframe Labor,
  Burden, and also Insurance
• Approx. 50,000/departure at 200 departures per
  year

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  HBJ BBJ G550
GTOW (lbs) 58,700 171,000 91,000
Wing Area (ft2) 587 1345 1137
Span (ft) 83.53 117 91.5
?1/4c (Degree) 30 34 27
T/W 0.43 0.32 0.352
W/S (lbf/ft2) 100 127 80
Vcruise (KTAS) 460 450 460
Hcruise (ft) 40,000 39,000 40,000
Range (nmi) 5700 6200 6500
AR 11.9 10 7.4
(L/D)max 17 17.5 18.4
Landing Distance (ft) 3224 2549 2767
Takeoff Field Length (ft) 4459 5643 5934
Cost (2006 Millions) 60 52 38
DOC (2006) 4070 2900 1820
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Outstanding Issues

• Stability
• Airfoil Selection and Aerodynamic Analysis
• Detailed Structural Analysis
• FAA Certification
• Research and Development Cost Analysis

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Questions
29
(No Transcript)
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Hydrogen Safety
.30 Caliber Armor Piercing
Placed in Bonfire
Charred Remains

• Explosion Hazard
• Leakage and Boil over Explosion
• Similar to Jet Fuel Characteristics
• Proper Care and Materials Needed
• Materials need to withstand very Low Temperatures
• Safety Relief Valves, Purging, Sensors, and
  Sophisticated Seals

• Proven As Safe as Jet Fuel
• No Detonation in Free Atmosphere
• Tested and Comply with Present Regulations
• Fire Hazard
• Boils off
• No Fire Carpet
• Fast Burn with Low Radiation

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Hydrogen Fueled Engine

• Hydrogen has lower Flame Temperature
• Reduced Turbine Inlet Temperature resulting in
  decrease in thrust
• Premixing almost necessary for proper combustion
• Other Slight Modifications needed

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Possible Fuel Cell APU

• Advantages
• Reduces Size of Engine
• Hydrogen Already onboard
• Can be stored in empty wings
• Reduced Noise

• Disadvantages
• Needs Several Megawatts of Energy
• Current APUs producing only a few Megawatts and
  outweighing turbines

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Fuel Supply/Engine Modifications

• High Pressure Pump
• Centrifugal Pump at approx. 150 RPM
• Move LH2 from tanks to combustor
• Heat Exchanger
• Transform Liquid to Gas before Combustion
• Needs to increase temperature to about 150-300 K
• Purging System
• Flush Air from Pipes
• Added Sensory
• Sense Leakage
• Proper Materials
• Perform at very low temperature

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Cryogenic Liquid Hydrogen

• Critical Temperature
• -400 F
• Critical Pressure
• 188 psia
• Cryogenic Storage
• -423 F
• 30 psia
• Requires 30 of Heating Value to Liquefy (15,000
  BTU/lbm)

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Cryogenic Tank

• Current Cryogenic Tanks
• Carbon Steel Alloy Outer Shell
• Perlite Insulating Layer with Mylar wrapped Inner
  Shell
• Al-Ni Inner Shell
• Future Cryogenic Tanks
• Carbon Fiber Outer Shell
• Graphite Fiber Resin Matrix Composite
  Insulation
• Advanced Composite Inner Shell

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Top View
8 ft
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FLOPS Input

• Moved Fuel from Wings to Fuselage
• Modified Heating Value to 54,000 BTU/lbm
• Added Composite Wing and Fraction of Structure
• Additional Weighted Factors for Fuel System to
  Include Cryogenics
• Increased Cost of Labor and Material

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Constraint Landing
39
Constraint Landing
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Constraint Landing
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Constraint Landing
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V-N Diagram Support

• Gust Velocities
• At VB, G 60.4 ft/s
• At VC, G 45 ft/s
• At VD, G 22.5 ft/s
• nGust 1 VG(KGGCLalpha)/(498W/S)
• KG .88u/(5.3 u)
• u 2W/S/(pcbargCLalpha)

43
Fan Study at 40,000 ft
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Engine Code Validation
Bypass Ratio Pressure Ratio Thrust (SLS) Thrust (11 km) SFC (11 km)
Cryoplane Engine 5.2 36.63 129.5 kN 24.77 kN 5.502 kg/(s-MN)
HBJ Engine Code 5.2 36.6 121.2 kN 33.3 kN 6.2 kg/(s-MN)
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Landing Gear

• Size calculation
• Used Business Twin equations
• Table 111 English Units

Diameter or Width (inches) A WwB
(where Ww is the weight applied on each wheel)
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Structural Layout

• Guidelines
• Never attach to skin alone
• Structural members should not pass through
  cabins, air inlets, etc
• Attach engine, landing gear, seats, etc to
  existing structural member
• Design redundancy into structure
• Mount control surfaces to spar
• Carry-through wing
• Added structural complexity with tanks above main
  cabin

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Spar Calculation
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Stability Formulas
Add cg equ. XbarxiWi/Wi
Static margin formula Xn-X bar/C bar
Equ for VHT
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C.G. Location
Component C.G. Location (ft)
Front Landing Gear 15
Crew 16
Baggage 25.5
Furnishings 33.5
Passengers 40
Miscellaneous 50
Fuel Tank 2,3,4 A 29.5
Fuel Tank 2,3,4 B 56.5
Fuel Tank 2,3,4 C 83.5
Fuselage 61.5
Component C.G. Location (ft)
Fuel Tank 1 74.5
Main Landing Gear 80
Wing 58.9
Nacelle 58.9
Engine 58.9
Vertical Tail 120
Horizontal Tail 121
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Stability Summary
  C.G. (ft) SM Weight np-cg (ft)
Wo 61.25 16.84 40827.00 1.30
Wo1/2 Fuel 61.45 14.22 42019.28 1.10
Wo1/2 Fuelcrew 60.50 26.55 42919.28 2.05
Wofuel 61.64 11.75 43211.55 0.91
Wofuelall cargo 61.74 10.57 57687.97 0.82
Woall cargo 59.38 41.07 43399.00 3.18
ready for take-off 61.74 10.57 57687.97 0.82
taxi take-off 61.73 10.67 57627.00 0.83
climb 61.63 11.88 56944.21 0.92
cruise 60.16 30.99 47378.55 2.40
decent 60.12 31.40 47260.55 2.43
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Second Look at Stability
Tank 5 ¼ of original tank 1 Tank 1 ¾ of
original tank 1
Tank 5 1/3 of original Tank 1 Tank 1 2/3 of
original Tank 1
Wfuel 1
Wfuel 5
Wfuel 1
Wfuel 5
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Additional Trade Studies
  Original 1/4 1/3
Wo 61.5 61.31 61.33
Wo1/2 Fuel 62.47 61.37 61.09
Wo1/2 Fuelcrew 62.03 60.63 60.35
Wofuel 63.95 61.62 61.10
Wofuelall cargo 61.73 60.28 59.91
Woall cargo 62.42 57.93 60.05

ready for take-off 61.73 60.28 50.94
taxi take-off 61.72 60.28 59.94
climb 61.62 60.26 59.95
cruise 60.13 59.99 60.07
decent 60.09 59.98 60.07
  Original 1/4 1/3
Wo 13.54 16.14 15.99
Wo1/2 Fuel 1.03 15.45 19.00
Wo1/2 Fuelcrew 6.67 25.11 28.68
Wofuel -18.16 12.17 18.89
Wofuelall cargo 10.61 29.65 34.41
Woall cargo 1.64 27.63 32.59

ready for take-off 10.61 29.67 34.07
taxi take-off 10.71 29.69 34.05
climb 12.07 29.95 33.95
cruise 31.33 33.39 32.31
decent 31.84 33.52 32.32
Center of Gravity (ft)
Static Margin ()
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Drag Polar
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1 Engine Out Calculations

• Fv qvSvCFßv?ßv/?ßdR
• qv (dynamic pressure at sea-level) 48.61
  slug/(ftsec2)
• Sv (vertical tail area) ft2
• CFßv (tail lateral lift force coefficient) 0.55
• ?ßv/?ß (free stream angle change) 0.99
• dR (rudder deflection) 0.35 radians
• T (thrust from 1 engine) 12500 lbf
• M (total moment) TdE-FvdV 0
• Calculate with distances from center of gravity.
  Solve for needed vertical tail area.

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Cross-wind Landing

• Cnß CnßwCnßfusCnßv-Fpß/(qSw)
  ?ßv/?ß(Xcg-Xp)
• Solve for Cnßv when Cnß 0
• Cnßv CFßv?ßv/?ß?vSv/Sw(Xacv-Xcg)
• Solve for Sv to find required vertical tail area

56
Cost Support

• Historical Trend
• AweaMbRc
• A 725.14
• a 0.1894
• b -.0519
• c 1.0777
• 50 Adjustment

• FLOPS
• Composite Wing/Structure Factor
• Increased Fuel System Factor
• Advanced Technology Factor

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DOC Support
58
DOC Support Contd
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DOC Support Contd
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DOC Support Cont