AAE 450 Spring 2008 Jesii Doyle 1/31/2008 Internal Structure, Mounting Materials Bulkhead Weight and Cost

AAE 450 Spring 2008 Bulkhead Weight and Cost  Assumptions –Max G-loading: 2G’s –Bulkhead position as shown in Figure 1 –Bulkhead loading as shown in Figure 1  Propulsion Options –LOX/LH2 –H2O2/RP-1 –HTPB/AP/Al *Dimensions and weights for each option provided by Dana Lattibeaudiere Structures Figure 1: Bulkhead Configuration Tank Engine External Skin Nozzle Bulkhead Bulkhead Inner Radius Nozzle Dia.

AAE 450 Spring 2008 Bulkhead Weight and Cost Structures Future Work  Internal support structure  CAD models - Internal structure

AAE 450 Spring 2008 Backup Slides  Prop. Specifications Structures

AAE 450 Spring 2008 Backup Slides  Prop. Specifications (Cont.)

AAE 450 Spring 2008 Backup Slides  MATLAB Code Results – Config. 2 LOX/LH2 Material Weight (kg)Cost (USD) Al 6061-T6160.2$ Al 7075-T6121.2$ Ti 6Al-4V137.6$29, Steel453.7$ Fiberglass109.5$250, Carbon Fiber138.6$151, H2O2/RP-1 Material Weight (kg) Cost (USD) Al 6061-T62.3$6.35 Al 7075-T62.4$6.50 Ti 6Al-4V3.2$ Steel4.7$2.09 Fiberglass2.3$5, Carbon Fiber2.1$2,305.80

AAE 450 Spring 2008 Backup Slides  MATLAB Code Results – Config. 2 (Cont.) HTPB/AP/Al Material Weight (kg) Cost (USD) Al 6061-T61.1$3.04 Al 7075-T61.1$3.12 Ti 6Al-4V1.5$ Steel2.3$1.00 Fiberglass1.1$2, Carbon Fiber1.0$1,105.00

AAE 450 Spring 2008 Backup Slides  Global Governing Equations –Variables: Gs = Max. G-loading g = Gravitational constant = m/s^2 m = Weight applied to bulkhead (kg) rnozzle = Nozzle radius (m) w = Applied unit line load (Pa) a = Rocket stage radius (m) b = Inner bulkhead radius (m) t = Bulkhead thickness (m) –Requirements: Displacement <= Max. Displacement (y = -0.01m) Applied Stress <= Yield Stress

AAE 450 Spring 2008 Backup Slides  Governing Equations – Config. 2 –Calculation of Thickness Maximum Displacement E = Modulus of Elasticity (Pa) ν = Poisson’s ratio

AAE 450 Spring 2008 Backup Slides  Governing Equations - Config. 2 (Cont.) –Applied Stress Assume cantilever beam with square cross- section F.S. = Factor of Safety

AAE 450 Spring 2008 Backup Slides  Manufacturing Cost Estimations –Aluminum manufacturing: 1.2x Mat’l Cost –Steel manufacturing: 1.6x Aluminum –Titanium manufacturing: 2x Aluminum –Fiberglass structure manufacturing: 1.7x Aluminum Additional Safety Factor 3.0 Required –Carbon fiber manufacturing: 2x Aluminum

AAE 450 Spring 2008 Backup Slides  Bulkhead Configuration 1 Tank Engine External Skin Nozzle Bulkhead Inner Radius F Nozzle Diameter Stage Diameter

AAE 450 Spring 2008 Backup Slides  MATLAB Code Results – Config. 1 LOX/LH2 Material Weight (kg)Cost (USD) Al 6061-T6257.9$ Al 7075-T6202.9$ Ti 6Al-4V233.0$20, Steel744.3$ Fiberglass177.1$198, Carbon Fiber227.6$104, H2O2/RP-1 Material Weight (kg) Cost (USD) Al 6061-T662.5$ Al 7075-T647.5$ Ti 6Al-4V54.6$4, Steel177.1$ Fiberglass42.1$47, Carbon Fiber54.0$24,678.00

AAE 450 Spring 2008 Backup Slides  MATLAB Code Results – Config. 1 (Cont.) HTPB/AP/Al Material Weight (kg) Cost (USD) Al 6061-T621.4$86.37 Al 7075-T615.7$73.16 Ti 6Al-4V21.3$1, Steel60.7$73.29 Fiberglass16.5$18, Carbon Fiber17.8$8,189.40

AAE 450 Spring 2008 Backup Slides  Governing Equations – Config. 1 –Calculation of Thickness Maximum Displacement E = Modulus of Elasticity (Pa) ν = Poisson’s ratio

AAE 450 Spring 2008 Backup Slides  Governing Equations - Config. 1 (Cont.) –Applied Stress Assume cantilever beam with square cross- section F.S. = Factor of Safety

AAE 450 Spring 2008 Backup Slides  Manufacturing Cost Estimations –Cost/Rivet: $0.73/rivet –Labor hour/Rivet: hr/rivet –Cost/Labor Hour: $52.00/hr –# Rivets = 6 * Circumference

AAE 450 Spring 2008 Backup Slides  References Cyr, Kelley, “NASA New Start Index Inflation Calculator,” Cost Estimating Web Site, NASA, May [ /inflateNASA.html. Accessed 1/28/08] Design Manual: Fiberglass Grating and Structural Products, Delta Composites, L.L.C., Houston, TX, Green, E.A., and Coulon, J.F., “Cost Considerations in Using Titanium,” AIAA Paper , Jun Noton, Bryan R., “ICAM - Manufacturing Cost Design Guide,” AIAA Paper , May 1981.

AAE 450 Spring 2008 Backup Slides  References (Cont.) Young, W.C., and Budynas, R.G., Roark’s Formulas for Stress and Strain (7th Edition), McGraw-Hill, 2002.