1. Project M.E.T.E.O.R. P07109: Flying Rocket Team
Andrew Scarlata, Geoff Cassell, Zack Mott, Garett Pickett, Brian Whitbeck, Luke Cadin, David Hall

2. Inner and Outer Shell ANSYS Stress Modeling (Chalice Design)
Payload
Composite-Honeycomb End Cap
Electronics
Micro IMU
(Inertial Measurement Unit)
Composite Outer Shell
Nitrous Oxide Tank
Pre-Combustion Chamber
HTPB Fuel Grain
Post-Combustion Chamber
Graphite Nozzle

3. Inner and Outer Shell ANSYS Stress Modeling (Embedded Design)
2x Aluminum End Cap
Siphon Tube
Composite Outer Shell
(Aluminum Inner Reinforced)
Nitrous Oxide Tank
Titanium Inner Shell
Combustion Chamber Inside
2x Outer Ring

4. Customer Specifications
Number
Design Specification
Importance
Units
Expected
Value
Current 1
Containment of Nitrous Oxide 5
psi
1000 2
Safety
P/F P 3
Operate within Material Temperature Range K
4700?
TBD 4
Max Allowable Acceleration (with respect to design) G
10-50
Nozzle Stress Testing (to determine if the graphite will rip away from body) 6
Cost
USD
10000 7
Structure to propellant ratio
2:10
1:2 8
Manufacturing feasibility 9
Reliable Ignition Method s
3-5 10
Tank Pressure Regulation
750 11
Satellite Implementation (diameter of top of rocket) cm
18 + 12
Accommodating thrust vectoring equipment

5. Bill of Materials

6. Mass Budget Total: 3.8 – 4.5kg Total: 5.9kg Chalice Concept
Embedded Concept:
Electronics/Guidance System: 1kg
Siphon Tube: 0.03kg
Composite Body: 0.85kg
Inner Shell: .56kg
Pre & Post Combustion Chambers: 0.15kg each
Outer Shell: 1.64kg
Injector Plate: 0.31kg
Outer Bands: 0.11kg each
Exit Nozzle: 0.71kg
Pressure Vessel: kg
Aluminium Shell: 0.76kg
Total: 3.8 – 4.5kg
End Caps: 0.52kg each
Total: 5.9kg

7. Composite Pressure Vessel (Chalice Concept)
Identified Company (CompositeX) to manufacture Custom Composite Pressure Vessel
Working pressure 1000psi
Holds 8 kg Nitrous Oxide
700 cubic inch volume
HDPE lined
1.4 lbs
Liquid Nitrous
Oxide
Nitrous
Oxide Vapor

8. Composite Pressure Vessel (Chalice Concept)
Helium Gas
Liquid Nitrous
Oxide

9. Composite Pressure Vessel (Chalice Concept)
Ideal gas law used to model helium pressure
p=m*R*T/V
Verified from pressure/ temperature data that Helium will remain gaseous
Compressibility factor ~1, so ideal gas assumption valid
Tank weights listed estimated from quote of 700ci=1.4 lbs
Also includes weight of Helium (case dependent)

10. Aluminum/Titanium Comparison

11. Mass Calculation

12. Mass Calculation Chalice Design, 7075-T6 Al 240mm OD, 1
Mass Calculation Chalice Design, 7075-T6 Al 240mm OD, 1.75mm Thickness, FS 1.25

13. Mass Calculation Embedded Outer Shell Design, 7075-T6 Al 180mm OD, 61mm ID, 1.3mm Thickness, FS 1.25

14. Inner Shell (fuel grain housing) Outer Shell (NOS/rocket housing)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Model Geometry
Inner Shell (fuel grain housing)
Outer radius: 2.40” (~61mm)
Inner radius: 2.36” (~60mm)
Height: ” (~545 m)
Mat’l: Aluminum 7075 T6
Outer Shell (NOS/rocket housing)
Outer radius: 1.75” mm ( m)
Inner radius: 1.25” ( m)
Height: 1.5” ( m)
Mat’l: Al 7075 T6 with Composite over-wrap
Composite: IM7 Carbon (fiber) / PEEK (matrix)

15. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Material Properties
Al 7075-T6
(Modeled as Isotropic)
Density: 2810 kg/m3
Longitudinal Mod., E1: 71.7e9 Pa
Poisson’s Ratio, v12: 0.33
Carbon/PEEK Composite
(Modeled as Orthotropic)
Density: 1600 kg/m3
Longitudinal Mod., E1: 71.7e9 Pa
Transverse Mod., E2: 10.2e9 Pa
Poisson’s Ratio, v12: 0.30
Shear Modulus, G12: 5.7e9
PEEK (matrix)
Density: 1376 kg/m3
IM7 Carbon Fiber (12,000 filaments)
(Modeled as Orthotropic)
Density: 1780 kg/m3
Longitudinal Mod., E1: 278e9 Pa
Poisson’s Ratio, v12: 0.20

16. Outer Shell (w/ composite)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (w/ composite)
Figure 1: Outer Shell of Imbedded Fuel Grain Design
(Meshed Elements – 8node93)

17. Outer Shell (w/ composite)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (w/ composite)
Figure 2: Outer Shell of Imbedded Fuel Grain Design:
Plot Results  Contour Plot  Element Solution  Stresses  von Mises stress

18. Outer Shell (w/ composite)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (w/ composite)
Figure 3: Outer Shell of Imbedded Fuel Grain Design:
Plot Results  Deformed Shape  Def + undeformed

19. Outer Shell (w/ composite)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (w/ composite)
Figure 4: Outer Shell of Imbedded Fuel Grain Design:
(Pressure & Constraints – Rotated view)

20. Outer Shell (w/ composite)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (w/ composite)
Figure 5: Outer Shell of Imbedded Fuel Grain Design:
(Pressure & Constraints - Front View)

21. Outer Shell (w/ composite)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (w/ composite)
Figure 6: Outer Shell of Imbedded Fuel Grain Design:
(Pressure & Constraints - Side View)

22. Inner Shell (All Aluminum)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Inner Shell (All Aluminum)
Figure 7: Inner Shell of Imbedded Fuel Grain Design
(Meshed Elements – 8node93)

23. Inner Shell (All Aluminum)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Inner Shell (All Aluminum)
Figure 8: Inner Shell of Imbedded Fuel Grain Design:
Plot Results  Contour Plot  Element Solution  Stresses  von Mises stress

24. Inner Shell (All Aluminum)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Inner Shell (All Aluminum)
Figure 9: Inner Shell of Imbedded Fuel Grain Design:
Plot Results  Deformed Shape  Def + undeformed

25. Inner Shell (All Aluminum)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Inner Shell (All Aluminum)
Figure 10: Inner Shell of Imbedded Fuel Grain Design:
(Pressure & Constraints – Rotated view)

26. Inner Shell (All Aluminum)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Inner Shell (All Aluminum)
Figure 11: Inner Shell of Imbedded Fuel Grain Design:
(Pressure & Constraints – Front view)

27. Inner Shell (All Aluminum)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Inner Shell (All Aluminum)
Figure 12: Inner Shell of Imbedded Fuel Grain Design:
(Pressure & Constraints – Side view)

28. Outer Shell (Aluminum only)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (Aluminum only)
Figure 13: Outer Shell of Imbedded Fuel Grain Design
(Meshed Elements – 8node93)

29. Outer Shell (Aluminum only)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (Aluminum only)
Figure 14: Outer Shell of Imbedded Fuel Grain Design:
Plot Results  Contour Plot  Element Solution  Stresses  von Mises stress

30. Outer Shell (Aluminum only)
Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (Aluminum only)
Figure 15: Outer Shell of Imbedded Fuel Grain Design:
Plot Results  Deformed Shape  Def + undeformed

31. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (Aluminum only)
Figure 16: Outer Shell of Imbedded Fuel Grain Design:
(Pressure & Constraints – Rotated view)

32. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (Aluminum only)
Figure 17: Outer Shell of Imbedded Fuel Grain Design:
(Pressure & Constraints - Front View)

33. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Outer Shell (Aluminum only)
Figure 18: Outer Shell of Imbedded Fuel Grain Design:
(Pressure & Constraints - Side View)

34. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 19: ELEMENT LAYERS

35. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 20: LAYER ORIENTATION AND THICKNESS

36. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 21: LAYER ORIENTATION AND THICKNESS continued…

37. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 22: COMPOSITE PROPERTIES

38. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 23: ALUMINUM PROPERTIES

39. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 24: FAILURE CRITERIA FOR COMPOSITES

40. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 25: INVERSE TSAI-WU STRENGTH RATIO INDEX

41. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 26: X-COMP OF STRESS

42. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 27: Y-COMP OF STRESS

43. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 28: X-COMP OF STRESS

44. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 29: SHEAR XY-DIR

45. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 30: SHEAR YZ-DIR

46. Inner and Outer Shell ANSYS Stress Modeling (Embedded Fuel Grain Concept)
Figure 31: SHEAR XZ-DIR

47. Top and Bottom Fixture Solidworks Stress Model (Embedded Fuel Grain Concept)
Model Geometry
Mass = kg
% Allowable Mass(2.31kg) = 22.5%
Volume = m3
Geometry is the same for both the top and bottom fixture

48. Material Properties, Loading, and Meshing
Top and Bottom Fixture Solidworks Stress Model (Embedded Fuel Grain Concept)
Material Properties, Loading, and Meshing
1000 psi
Al 7075-T6
Density: 2810 kg/m3
Modulus of Elasticity: 71.7 GPa
Shear Modulus: 28 GPa
Meshing done with Solidworks and Cosmos finite element analysis
Elements: 25306
Nodes: 49277

49. Factor of Safety Results
Top and Bottom Fixture Solidworks Stress Model (Embedded Fuel Grain Concept)
Factor of Safety Results

50. External Shell Solidworks Stress Model (Embedded Fuel Grain Concept)
Model Geometry
Mass = kg
% Allowable Mass(2.31kg) = 71.0%
Volume = m3

51. External Shell Solidworks Stress Model (Embedded Fuel Grain Concept)
Material Properties, Loading, and Meshing
Al 7075-T6
Density: 2810 kg/m3
Modulus of Elasticity: 71.7 GPa
Shear Modulus: 28 GPa
1000 psi
Meshing done with Solidworks and Cosmos finite element analysis
Elements: 43804
Nodes: 87448

52. External Shell Solidworks Stress Model (Embedded Fuel Grain Concept)
Factor of Safety Results

53. Internal Shell Solidworks Stress Model (Embedded Fuel Grain Concept)
Model Geometry
Mass = kg
% Allowable Mass(2.31kg) = 244%
Volume = m3

54. Internal Shell Solidworks Stress Model (Embedded Fuel Grain Concept)
Material Properties, Loading, and Meshing
Al 2024
Density: 2780 kg/m3
Modulus of Elasticity: 73.1 GPa
Shear Modulus: 28 GPa
1000 psi
Meshing done with Solidworks and Cosmos finite element analysis
Elements: 34919
Nodes: 68256

55. Internal Shell Solidworks Stress Model (Embedded Fuel Grain Concept)
Factor of Safety Results

56. External Shell Composite Design (Embedded Fuel Grain Concept)

57. External Shell Composite Design (Chalice Concept)

58. Al2O3 Post Combustion Chamber
Post Combustion Chamber ANSYS Thermal Model (Embedded Fuel Grain Concept)
Model Geometry
Al2O3 Post Combustion Chamber
Outer radius: 1.25” ( m)
Inner radius: 1” ( m)
Height: 1.5” ( m)
Al 7075-T6 Housing (0.5 mm)
Outer radius: 1.75” mm ( m)
Inner radius: 1.25” ( m)
Height: 1.5” ( m)

59. Post Combustion Chamber ANSYS Thermal Model (Embedded Fuel Grain Concept)
Material Properties
Al2O3
Density: 3970 kg/m3
Specific Heat: J/(kg-K)
Thermal Conductivity: variable
Al 7075-T6
Density: 2810 kg/m3
Specific Heat: 960 J/(kg-K)
Thermal Conductivity: 130 W/(m-K)
Assumptions
Constant Aluminum properties
Chamber ends are adiabatic
Constant film coefficients
Constant bulk temperatures

60. Post Combustion Chamber ANSYS Thermal Model (Embedded Fuel Grain Concept)
Meshed Model
Volumes meshed using ANSYS SmartSize 1 with tetrahedral elements
Nodes: 9,589
Elements: 5,602

61. All nodes initially set to 298 K
Post Combustion Chamber ANSYS Thermal Model (Embedded Fuel Grain Concept)
Boundary Conditions
Outer Surface
Film coefficient, h = 5 W/(m-K)
Bulk temperature, T∞ = 298 K
Simulates free convection of N20 on Al housing
All nodes initially set to 298 K
Inner Surface
Film coefficient, h = 300 W/(m-K)
Bulk temperature, T∞ = 3000 K
Simulates convection of the propellant gas inside the combustion chamber

62. Post Combustion Chamber ANSYS Thermal Model (Embedded Fuel Grain Concept)
Transient Results

63. Post Combustion Chamber ANSYS Thermal Model (Embedded Fuel Grain Concept)
Discussion of Results
This model demonstrates heat transfer across multiple ANSYS volumes, which will be necessary to derive a film coefficient from thermocouple data
A transient analysis was also performed by hand using ANSYS input conditions with results matching ANSYS output to within 100 Kelvin. The transient model is considered validated for this test case.

64. Post Combustion Chamber ANSYS Thermal Model (Engine Core)
Future Models
A model of the post combustion chamber and nozzle is being developed to utilize data that will be collected by the test stand team.
The model will be used to back out an average film coefficient and to determine if the engine structure will meet the Guidance burn time of 50 seconds.

65. Flying Rocket Ignition System (Darlington configure transistors)
R3 Igniter load (Nicrome Wire)
Fc = 90 hz
V2 = PWM from MSP430 F1-69

66. Transistor Characteristics
2SC7401S

67. 2SC5001

68. Output Characteristics
Current
Duty Cycle

69. Ground Ignition System

70. Output Characteristics
Current
Time

71. Power Source 7.4 volt - 700mAh 20C Li-Poly Pack
Discharge rate of 14 amps
6mm x 36mm x 55mm 50 grams

72. Discharge Characteristics
Max = 20.09
Avg = 18.9
Run Time = 2:32 min

73. Questions?