Presentation 2 Vehicle Systems - Daedalus 1
Outline Structures Nosecone Body tubes Bulkheads Fins Tail Cone Recovery System Layout Testing Propulsion Ox Tank Plumbing Injector Chamber Nozzle Testing Hydrostatic Cold Flow Hot Fire System Validation Test data presentation Trajectory System Operating space (altitude) Flight Profile (engine test) 2
Slide Structure Design & Analysis Construction Validation 3
Nose Cone Design Discussion -Materials: Fiberglass sheet 60 minute cure epoxy resin -High tensile and compressive strength FR = 3:1 Anaylsis - Half-Power profile -y = R x L - Fineness Ratio -STAR-CCM+ -Simulations @ Mach 0.8
Nose Cone Construction -Wet-lay fiberglass strips into mold halves, nose cone -Fill, prime, and paint Flight Performance -Withstood flight loads as expected -Minor scratches from landing
Bulkheads Design Material Aluminum 6061-T6 Considerations Attachment methods Well nut Nut/bolt Rivets JB weld Loading Ease of Assembly Layout 5 main bulkheads Recovery Bulkhead Connections: Recovery well nuts Payload bolt/nut Body Tubes JB weld Joint Bulkhead Connections: Body Tubes JB weld Thrust Bulkhead Connections: Body Tubes JB weld Top Well nut Bottom Nut/Bolt 6
Body Tubes Analysis z+45 /-45 weave angle Fiber/matrix modeling difficulty Estimated Load ~1250 lbf Flight Proven Flight Results Construction 0 (axial) Resistant to longitudinal bending 90 (hoop) 45 Weakened while finishing rough surfaces, slight fracture upon landing Resists internal/external pressure Ideal to resist pure torsion 7
Fins & Stability Airfoil Design NASA SC-010 CFD optimization Planform Design RASAero optimization Dynamic Stability RASAero w/crosswind 8
Fins Design Materials Carbon Fiber Cloth High Density Foam Aluminum Base Epoxy Considerations Light Weight Resist Fin Flutter Maintain Structural Integrity Construction CNC aluminum bases CNC fin mold Cast foam fin cores Fuse core and base with epoxy Vacuum resin transfer process Attach to body with ¼ bolts Bondo fillet around the aluminum base Flight Performance Withstood flight loads
Tail Cone Design Discussion Analysis -Lightweight & Heat Resistant -CFD in STAR-CCM+ stagnation region -Strong enough to hold fins -Material: Al 6061-T6 -Made from rolled aluminum sheet, welded at seam 1.22 calibers 1.25 calibers 7.3 14.5
Recovery System Overview (3) Apogee (2) Coast Dual-Deployment Recovery System Key Features: Dual Deployment design to minimize drift Single point of rocket separation Integration of Advanced Retention Release Device to release main (ARRD) (4) Drogue Deployment at Apogee, Descent @ 90 ft/s (1) Motor Ignition (5) Main Deployment at 1500 AGL, Descent @ 20 ft/s (6) Landing 11
Recovery System Overview Drogue Parachute Configuration Main Drogue 5 Tubular Nylon 15 Tubular Nylon Shock Cord Main Parachute Configuration 28 Tubular Nylon + 6 Kevlar Y-Harness = 34 12
Initial Design Utilizing Line Cutters Preliminary Design Overview: Dual Deployment system utilizing line cutters to deploy main parachute at desired altitude Both main and drogue are ejected from the vehicle at apogee System Concerns A pre-mature deployment of the main parachute at Waco launch Redundant line cutters on same zip-tie proved to be faulty in conditions that are difficult to test More reliable and testable solution is desired Line Cutter V3 Key Dimensions Length 5.25 Weight 3.75 oz Charge.75 grams Pyrodex p 13
Current Recovery System Recovery Bulkhead: Top View U-Bolt Binding Posts connect E-Match to Electronics Bay Ejection Pod Showing E-match to Pyrodex Charge U-Bolt ARRD Recovery Bulkhead Redundant Ejection Charges connected with binding posts to electronics bay 7 gram charge Pyrodex P 4 x (4-40 Shear Pins) 2 (U-Bolts) distribute opening force across entire bulkhead ARRD mounted through bulkhead 14
ARRD (Advanced Retention Release Device) ARRD implemented as alternative to line cutters Link between drogue and main parachute from apogee to 1500 AGL Activated by pyrodex P charge Installed through the recovery bulkhead Advantages of ARRD vs. Previous Designs Main parachute is kept in the recovery bay Electronic wire no longer required to run from bulkhead to main parachute Utilization of deployment bag keeps the recovery bay organized ARRD Key Dimensions Length w/o shackle 2.125 Diameter 1.375 Weight 2.75 oz Pyrodex P Charge.25 grams 15
Opening Force [lbf] Opening Force Calculation Impulse Momentum Theory Transfer of momentum between vehicle and displaced air mass provides opening force Function of inflation time Force as a function of inflation time Deployment inflation window: 100 ft/s Estimate Opening Force: 380-450 lb f Recovery System Max. Load Ratings 1200 1000 800 600 400 Opening Force vs. Inflation Time Parachute Inflation Window Tubular Nylon Shock Cord 4000 lb 200 Fruity Chutes Swivel 3000 lb 3/8 Quick Link 6000 lb Kevlar Y-Harness 6000 lb 0 0 0.5 1 1.5 2 2.5 3 3.5 Time [s] ARRD 2000 lb 16
NP-915 Icarus II I SP avg m Prop Burn time Peak Thrust Average Thrust Impulse Summary Specifications 220 s 2.47 lbs/s 11.8 s (8.4 liq) 915 lbf 542 lbf 6411 lb-s Exhibition Engine 70% FR 20% Hydrotest Verified 20% Cold Flow Verified 30% Static Test Verified Completion pending infrastructure improvements
Hybrid Engine Liquid Oxidizer: Nitrous Oxide Solid Fuel: HTPB
Pressure (psi) Nitrous Oxide Vapor pressure dependent on ambient temperature Two phases in oxidizer tank: Liquid and gas Climate Control Controlling fill tank temperature Regulate engine performance Predicted Thrust Temp: 85 F Oxidizer 1200 N 2 O Vapor Pressure v. Temperature 1000 800 600 400 200 Predicted Thrust Temp: 60 F 0 0 20 40 60 80 100 120 Temperature ( F)
Fuel: HTPB HTPB Solid Fuel Grain Regression rate Geometry 5 in OD 3.5 ID HTPB Fuel Grain 2.3 Pre-Combustion Chamber 21.3 Fuel length Predictability Fiberglass Insulation ABS Pre-CC Fiberglass Insulation n r avg = ag liquid (avg) r avg = 0.068 in/s Partial Burn r avg = 0.115 in/s Full Burn
Propellant Solid HTPB and Liquid Nitrous Together Ideal FO ratio of ~0.154 Looking for equivalence ratio of 1 Φ actual Φ stoich = 1 where Φ actual = m fuel m oxidizer
Mass (lb) Tank & Plumbing Maximum N 2 O (l) Mass v. Temperature Composite Overwrapped Solid Aluminum structure 50 40 30 20 10 0 0 20 40 60 80 100 Temperature ( F) Luxfer T144A Tank Specifications Icarus Requirement Service Pressure 3600 psi 1000 psi 18.9 lbs. vs. 46.9 lbs. Volume 1100 in 3 - Max Nitrous Mass (@ 95 F) 23.4 lb (0.02 lbm/in 3 ) 22 lb
Tank & Plumbing Minimize Weight Length Leaks Plumbing Specifications Minimum Thickness 0.100 Service Pressure 5200 psi Weight 1.22 lb
Ball Valve Actuator Servo Torque BVA Specs 611 oz-in 4 Bar Linkage Output 1100 oz-in Transferable between engine systems
Injector Increase Regression Rate ~20% Specifications Orifice Area 0.0675 in 2 Best Mixing m 2.1 lbs/s -Result of vortex injection -Localized Increase
Combustion Chamber Specifications Operating Pressure Test Pressure Length OD Thickness 400 psi 520 psi 30 in 5.5 in 0.25 in Factor of Safety >2
Nozzle Specifications ε 4.5 A t 1.1 in 2 V e m 7461 ft/s 2.75 lb/s
Hydrostatic Testing Process Injector to Tank - pressure tested to 1400 PSI Cap coin in place Tank to Chamber & Nozzle- pressure tested to 400 PSI Surface Area: 12.75 in 2 Service pressure: 400 psi Experiences 5100 lbf Cap Area: 19.63 in 2 Test pressure: 260 psi Proof pressure: 375 psi
Hydrostatic Testing Results Issues with various gasket materials V2 V3 Heat affected zone failure V1 Buna O-ring seal Verified April 28, 2016 V1
Engine Testing: Cold Flow Oxidizer runs through engine system without ignition Allows for complete testing of system and infrastructure before static fire Predicted Recorded Data Time of cold flow 272-241.7 = 30.3 sec
Static Engine Testing Results (Video)
Static Engine Testing Results 32
Daedalus Performance OVERFILL
10k Target Flight SpacePort, NM Daedalus [Icarus] 100 MC Value ±1σ Loaded Weight Mass N2O 107.3 lb - 14.5 lb - Apogee 9838 ft ±3.5% Peak Mach Peak Accel. 0.65 ±1.5% 6.12 G ±2.0% Rail Exit 94 ft/s ±3.0%
10k Target Flight SpacePort, NM Daedalus [Icarus] 100 MC Value ±1σ Loaded Weight Mass N2O 107.3 lb - 14.5 lb - Apogee 9838 ft ±3.5% Peak Mach Peak Accel. 0.65 ±1.5% 6.12 G ±2.0% Rail Exit 94 ft/s ±3.0%
05/10/16: Empirical Load Cell SpacePort, NM Daedalus [Icarus] 100 MC Load Cell Pressure Trans. Mass N2O 25 lb 25 lb Apogee 11,619 ft 20,393 ft Peak Mach 0.56 1.04 Peak Accel. 2.9 G 5.0 G Rail Exit 65 ft/s 87 ft/s