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Propulsion Back-Up Slides. Propulsion. Engine Performance Characteristics. AAE 450 Spring 2008. Propulsion. Propellant Stage 1 - Hydrogen Peroxide and HTPB Stage 2,3 - AP/HTPB/Al Pressurant Nitrogen 12 MPa 1 st Stage Only. Propellant and Pressurant Cost. Propulsion.
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Propulsion Back-Up Slides AAE 450 Spring 2008 Propulsion
Engine Performance Characteristics AAE 450 Spring 2008 Propulsion
Propellant Stage 1 - Hydrogen Peroxide and HTPB Stage 2,3 - AP/HTPB/Al Pressurant Nitrogen 12 MPa 1st Stage Only Propellant and Pressurant Cost AAE 450 Spring 2008 Propulsion
Mixture Ratio Optimization O/FHybrid ~ 6 Hybrid – H2O2/HTPB
Change in Performance • Min Alt. for no separation – 21,900 m • Separation Ae/At = 3.25 • Isp,v = 283.1 • Isp, sl = 245.3 • % Diff Isp From Launch Alt = 16 %
Engine Sizing The amount of propellant required for each rocket/stage was determined in Model Analysis Inert mass fraction, finert, was optimized between the structures and propulsion groups for final design 12<#>
Engine Cost Cost of Engines calculated from equations based on mass flow, thrust, and dry weight Cost equations are extrapolated from historical values 13<#>
Historical Failure Probability • U.S. Solid Rocket Systems (Failures/Attempts) • 6 / 412 (1.4%) Failures between 1980-20041 • 19 / 3382 (0.56%) Failures between 1964-19982 • Solid Propulsion Failure Rates (Failures/Attempts) • Upper Stage 0.0161 161/10000 • Monolithic 0.0025 25/10000 • Segmented 0.0077 77/10000 • Total 0.0056 56/10000 AAE 450 Spring 2008 14<#> Propulsion – Propellants
Engine Performance Characteristics AAE 450 Spring 2008
Engine Performance Characteristics AAE 450 Spring 2008
Engine Performance Characteristics AAE 450 Spring 2008
Hybrid and Solid Standard Deviations Hybrid Propellant For hybrid propellants, we cannot find historical standard deviations. The two percent deviations for liquid and solid propellant are added together to calculate a hybrid propellant percent standard deviation. Percent Deviations for Each Propellant Type AAE 450 Spring 2008 Propulsion
LITVC • 1st and 2nd stage control • 4 valves per stage for perpendicular to centerline injection of H2O2 • 1st stage tap-off of main H2O2 tank • 2nd stage bring own H2O2 pressurized tank • Considered main part of engine for weight/cost due to low complexity • Costs include: • 4 valves per stage @ $100/valve • Extra propellant • Extra tank on 2nd stage AAE 450 Spring 2008 Propulsion
LITVC Calculations • Input • Thrust (vac) • Mass Flow rate • Stage Burn Time • Calculations Image courtesy E. Glenn Case IV1 AAE 450 Spring 2008 Propulsion
Ideal Mass Ratios AAE 450 Spring 2008 Propulsion Team
References Heister, Stephen D. Humble, R. W., Henry, G. N., Larson, W. J., Space Propulsion Analysis and Design, McGraw-Hill, New York, NY, 1995. Javorsek, D., and Longuski, J.M., “Velocity Pointing Errors Associated with Spinning Thrusting Spacecraft,” Journal of Spacecraft and Rockets, Vol. 37, No. 3, 2000, pp. 359-360. Klaurans, B. “The Vanguard Satellite Launching Vehicle,” The Martin Company. No. 11022, April 1964. Knauber, R.N., “Thrust Misalignments of Fixed-Nozzle Solid Rocket Motors,” Journal of Spacecraft and Rockets, Vol. 33, No. 6, 1996, pp. 794-799. Sutton, George P., Biblarz, Oscar “Solid Propellants,” Rocket Propulsion Elements, 7th ed., Wiley, New York, 2001. Ventura, M., “The Lowest Cost Rocket Propulsion System,” General Kinetics Inc, Huntington Beach, CA, Jul. 2006. Tsohas, John. AAE 450 Spring 2008 Propulsion
Helium – Priced at $4.87 per cubic meter of gas Balloon – Price quote from Aerostar International Gondola- Constant Price of $13,200 Balloon Design AAE 450 Spring 2008
Balloon Model Buoyancy • Free Body Diagram • Two forces acting on Spherical Balloon • Buoyancy Force • Defined by difference between masses of lifting gas and air multiplied by gravitational constant • Weight Weight
Derivation of Balloon Dimensions • Lifting Coefficient • Ρg is density of lifting gas • Ρa is density of air • Boyle’s and Gay Lussac’s laws • Rho is density • P is pressure • T is Temperature
Derivation of Balloon Dimensions Continued • Combine equations to determine lifting coefficient for different heights • Take into account 95% gas purity and standard excess of 15% lifting gas • Final Equation for Volume of Gas in relation to Mass • V is volume of lifting gas • Mtotal is total mass
Balloon Cost Cost Trend Equation • Y = -0.0011X2 + 30.62X + 3111.1 • Y = Cost • X = Balloon Payload AAE 450 Spring 2008
Gondola Costs • Structures Cost of $1,200 • Material • Welding • Riveting • Avionics Cost of $12,000 • One Battery • Sensors • Total Gondola Cost of $13,200 Provided by Sarah Shoemaker, Structures Group, and Avionics Group
Determination of rise time • Assumptions • Constant sphere • Constant CD = 0.2 • Barometric formula • Kinematic viscosity variation with temperature • Constant acceleration over time steps of 1 second DHorizontal Lift Weight DVertical AAE 450 Spring 2008 Propulsion
Thanks to Jerald Balta for modifying the balloon code to output this.
Thanks to Jerald Balta for modifying the balloon code to output this.
Ground Support and Handling Cost Modifier • Handling – Personnel required for handling of fuels, toxic materials, etc • Ground Support – Based on estimation of salaries of necessary personnel • Assumed $100/hour salary • Six engineers and one project manager
References • Defense Energy Support Center, “MISSILE FUELS STANDARD PRICES EFFECTIVE 1 OCT 2007,” Aerospace Energy Reference, November 2007 • Larson, W.J., Wertz, J.R., "Space Cost Modeling," Space Mission Analysis and Design, 2nd ed., Microcosm, Inc., California and Kluwer Academic Publishers, London, 1992, pp. 715-731. • Smith, Mike, Phone Conversation, Aerostar International, February 15, 2008 • Tangren, C.D., "Air Calculating Payload for a Tethered Balloon System," Forest Service Research Note SE-298, U.S. Department of Agriculture - Southeastern Forest Experiment Station, Asheville, North Carolina, August 1980.
Nozzle (specs and CAD) Conical Nozzle 12° Conical Nozzle Conical because of solid and hybrid propellants. All stages have same nozzle Sizing Nozzle Dimensions based off of the exit area from MAT output ε = 60; Throat Area and Throat Diameter are determined.
Test Facilities • Purdue (Zucrow High Pressure Laboratories) • Propellants/ Oxidizers currently tested: H2O2, Liquid Hydrocarbon, LOX • For Hybrid test we need H2O2, and (excluding 5 kg Stage1) all other engines can be tested at Purdue. • Table below shows Zucrow’s HPL capabilities. • Kelly Space and Technology • Up to 20,000 lbf (88,960 N) thrust stand capabilities. • Propellant tanks and data acquisition systems already at test site. • Located in San Bernardino, CA. • Can test our 5 kg: stage 1 engine at 75,073 Newtons of thrust.
References 1 Scott Meyer, private meeting at Zucrow Test Laboratories. February 8th, 2008. Test facility overview and private tour of the large rocket test stand. 2 Kelly Space and Technology. Jet and Rocket Engine Test Site (JRETS) URL: http://www.kellyspace.com/ [last updated Jan. 31st 2008]. 3 MAT Output file from AAE 450 course website. 5kg, 1kg, and 200 g caseshttps://engineering.purdue.edu/AAE/Academics/Courses/aae450/2008/spring/large/3_5kg/v125/5kg_MAT_out_v125.txt AAE 450 Spring 2008