Propulsion Systems Design • Lecture #18 - October 29, 2020 • Rocket engine basics • Survey of the technologies • Propellant feed systems • Propulsion systems design © 2020 David L. Akin - All rights reserved http://spacecraft.ssl.umd.edu U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 1 Grading Rubric for Team Project #2 • Overall design (interior/exterior views, dimensioned 3- view, functionality in mission application) – 10 pts • Habitability design (crew accommodations, usage allocation, galley, waste management, windows) - 10 pts • Life support systems design (trade studies, installation in CAD design, provision of resupply) – 10 pts • Accommodation of visiting vehicles (docking ports, hatches, cargo interfaces) – 10 pts • EVA accommodations (airlock(s)/suitports, suit donning/doffing/recharging stations, dust remediation) – 10 pts U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 2 Grading Rubric for Term Project #2 • Logistics management (volume allocation, crew access, ability to restock) – 10 pts • Concept of operations (How will the habitat be used? “day in the life”… how well does it fit the mission?) – 10 pts • Presentation quality (“telling the story”, engaging the reader, adhering to principles from class) - 10 pts • CAD quality (details, fidelity, complexity) - 20 pts • “Above and beyond” (extra effort outside of nominal expectations) - 10 pts extra credit U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 3 Propulsion Taxonomy Mass Expulsion Non-Mass Expulsion Thermal Non-Thermal Ion Chemical Non-Chemical Solar Sail MPD Laser Sail Nuclear Monopropellants Bipropellants Beamed Electrical Microwave Sail Cold Gas Solar MagnetoPlasma Solids Hybrids Liquids Air-Breathing ED Tether Pressure-Fed Pump-Fed U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 4 Thermal Rocket Exhaust Velocity • Exhaust velocity is γ − 1 γ 2γ ℜTo pe ve = 1 − γ − 1 M¯ ( po ) where M¯ ≡ average molecular weight of exhaust Joules ℜ ≡ universal gas constant = 8314.3 moleoK γ ≡ ratio of specific heats ≈ 1.2 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 5 Ideal Thermal Rocket Exhaust Velocity • Ideal exhaust velocity is 2γ ℜTo ve,ideal = γ − 1 M¯ • This corresponds to an ideally expanded nozzle • All thermal energy converted to kinetic energy of exhaust • Only a function of temperature and molecular weight! U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 6 Thermal Rocket Performance • Thrust is · T = mve + (pe − pamb)Ae • Effective exhaust velocity · Ae c T = mc ⟹ c = ve + (pe − pamb) Isp = m· ( go ) • Expansion ratio 1 γ − 1 1 γ γ A γ + 1 γ − 1 p γ + 1 p t = e 1 − e Ae ( 2 ) ( po ) γ − 1 ( po ) U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 7 Nozzle Design • Pressure ratio p0/pe=100 (1470 psi-->14.7 psi) Ae/At=11.9 • Pressure ratio p0/pe=1000 (1470 psi-->1.47 psi) Ae/At=71.6 • Difference between sea level and vacuum Ve γ − 1 γ − 1 γ γ ve1 po − pe1 = γ − 1 γ − 1 ve2 γ γ po − pe2 • Isp,vacuum=455 sec --> Isp,sl=397 sec U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 8 Solid Rocket Motor From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 9 Solid Propellant Combustion Characteristics From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 10 Solid Grain Configurations From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 11 Short-Grain Solid Configurations From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 12 Advanced Grain Configurations From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 13 Liquid Rocket Engine U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 14 Liquid Propellant Feed Systems U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 15 Space Shuttle OMS Engine From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 2001 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 16 Turbopump Fed Liquid Rocket Engine From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 17 Sample Pump-fed Engine Cycles From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 18 Gas Generator Engine Schematic U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 19 SpaceX Merlin 1D Engines U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 20 Falcon 9 Octoweb Engine Mount U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 21 Staged-Combustion Engine Schematic U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 22 RD-180 Engine(s) (Atlas V) U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 23 SSME Powerhead Configuration U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 24 SSME Engine Cycle From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 25 Liquid Rocket Engine Cutaway From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 2001 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 26 H-1 Engine Injector Plate U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 27 Injector Concepts From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 28 TR-201 Engine (LM Descent/Delta) U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 29 Solid Rocket Nozzle (Heat-Sink) From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 30 Ablative Nozzle Schematic From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 31 Active Chamber Cooling Schematic From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 32 Boundary Layer Cooling Approaches From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 33 Hybrid Rocket Schematic From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 34 Hybrid Rocket Combustion From G. P. Sutton, Rocket Propulsion Elements (5th ed.) John Wiley and Sons, 1986 U N I V E R S I T Y O F Propulsion Systems Design ENAE 483/788D - Principles of Space Systems Design MARYLAND 35 Thrust Vector Control Approaches From G.