Upload
er-riddhesh-patel
View
224
Download
4
Tags:
Embed Size (px)
DESCRIPTION
Space propulsion system and structures
Citation preview
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 1
Space Transportation Systems
Propulsion and Structures
Status of Discussion of the DGLR Expert CommitteeDGLR-Fachausschuss S4.1
R. Lo (AI), W. Zinner (Astrium RT), R. Pernpeintner (MT Aerospace )
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 2
Introduction
• The DGLR S4.1 Working Group on Space Transportation Systems (Fachausschuss S4.1 Raumtransportsysteme) is a forum for members of agencies, institutions, industry and universities. Gathering and analysis of information, argumentations about past, present and future spacetransportation systems are the objectives of this particular group.
• Analysis and documentation is coordinated around the topics– Demand & Market– System Concepts & Subsets– Propulsion, Structures & Subsystems
(System related aspects)– Missions & Operations (incl. ground infrastructure)– Cost (Development, Production & Operation)– Projects / Programmatic (Development & Demonstration)
• This paper presents the status of information and analysis of DGLR-FAS S4.1 about propulsion and structures.
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 3
Content of Presentation
Jet and Rocket Propellant ClassificationPropellants in Use / Propellants of Current Interest Environmental Benignity: TEHF+Green HybridsDesign Examples of Liquid Rocket EnginesStructures of Liquid Propulsion StagesDesign Examples of Solid Rocket Motors Structures of Solid Propulsion Stages Design Examples of Hybrid Rocket Motors Structures of Hybrid Propulsion StagesPropulsion, Structures and Subsystems - Results and FactsSummary and Outlook
Σ: Propellants + Liquid-, Solid-, Hybrid-Propellant Engines
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems
Jet Propellant Classification and Consumption
Propulsion type Characterisation Remarks ~ Annual consumption*)
Airbreathing: Mixed hydrocarbons
Jet propellant / Aviation fuel
53,91 Mio.t /0,897 Mio. t
Rocket: LOX/LH2 < fully cryogenic 3-4000 tLOX/HC < semi cryogenic 9500 tN2O4/Hydrazines < hypergolic storable 10000 tN2O/Polymere < green storable 10-50 t**)AP/HTPB/Al < Solid storable 9000 t
4
*) Rockets: estimated average 2006/6-2007; **) SS1 2003-2004 SL tests + 6 flights
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 5
(AI) Overview of Propellants in Use
Propellants currently used in operational space systems:Number of stages with individual propellants launched 1/2006 to 6/2007:
LOX/ LH2
LOX/ Kero
NTO/ UDMH
NTO/ UH25 MMH
Solids
China 6 0 30 0 2
EU 14 0 0 0 14
India 1 0 2 4 20
Japan 10 0 0 0 18
USA 13 20 11 0 74
Russia 0 104 85 0 5
Ukra-ine
0 18 15 0 5
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 6
(AI) Propellants of Current Interest
Some physical and chemical liquid propellant characteristics:
Prop. Fp °C Bp °C Sol.Ds. Liqu.Ds. Rem. + (Isp 68:1)
LH2 -259,2 -252,8 0,088 0,0711 +24% „100% slush“ (391)LOX
CH4 -182.5 -161.5 0.466 0.423 Tcrit = -82,7°C (311)LOX
C3H8 -190,0 -42,1 0,582 7,1 bar VP at 20°C (~305)LOX
O2 -218.8 -183.0 1.46 1,14 TEHF= MpMission/L50 = 0
N2O4 -9.3 21.15 1.45 TEHF = 11-14
H2O2 -0.4 150.2 1.44 TEHF = 3-5
RP-1 ~-40 177-274 0.820 TEHF = 0,09; (300) LOX
N2H4 1.4 113.5 1.004 TEHF = 2,8; (292)N2O4
UDMH -57.0 63.0 0.793 TEHF=3; (287)N2O4
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 7
(AI) Environmental Concerns: Green Propellants/greenHybrids
• Environmental concerns refer to storage and handlingrather than emissions !
• Comparison of space transportation emissions (100 launches/a)with air traffic pollution and terrestrial traffic yields 1 : 2000 : 5500
• HCl emission of solid rockets : coal combustion = ~1/200• In abs. numbers: solid rockets = 0,01MT HCl/a; coal combus-tion:1,8MT; volcanoes: 7,8 MT; oceans: 300MT
Prop. Fp °C Bp °C Density Fpkg/l
Density Bpkg/l
Rem.
N2O -90.8 -88.5 1.22 Tcrit: 36,6°CPcrit: 7,27MPTEHF = 0(254)HTPB
Polyethylene ~110 (477) 0,92-0,96 n.a. 20°C
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 8
Design Examples of Liquid Rocket Engines
8
Basic Principle of a Liquid Propulsion System
Pressurization System:Pressure- or turbopump-fed systems raise the pressure above the operating pressure of the engine
Thrust Chamber Assembly:Generates thrust by efficiently converting the propellant chemical energy into hot gas kinetic energy
Fuel/OxTank
Turbopump
CombustionChamber
Nozzle
Thrust
The Thrust Chamber is the Heart of All Liquid Propellant Rocket Engines
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 9
Design Examples for Liquid Rocket Engines
Non-Storable (cryogenic) PropellantsLiquefied gases stored at very low temperaturesLiquefied to minimize the sizes of tanks needed to store themMost common propellant used for today's rocket applications are:
Fuel: Liquid hydrogen (LH2)Oxidizer: Liquid oxygen (Lox)
Pros■ Lox/H2 provides the highest specific impulse (~450 sec)■ Lox/H2 is environmentally friendly■ Non corrosive
ConsThermally insulated tanksPrior to loading, tank evaporation to avoid frozen particlesVenting on the launch pad and refillingLow temperature designExpensive
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 10
Design Examples for Liquid Rocket Engines
Storable PropellantsDistinction between earth and space storable propellantsLiquid at environmental conditions (earth or space)Storable for a long time in sealed tanksMost common propellants for today's rocket applications are:
Fuel: Kerosene, MMH, UDMH, N2H4Oxidizer: N2O4
Pros■ Stable at ambient temperature and pressure, i.e. no boil-off■ Non reactive with tank materials■ Instant readiness of the rocket engine
ConsMedium performanceHypergolics are extremely toxic (N2O4/MMH)Surface contaminationHigh handling safety precautions
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 11
Design Examples for Liquid Rocket Engines
Engine CycleThe engine cycle (thermodynamic cycle) terminology refers to the source of energy to drive the engine's turbines.
Cycle AnalysisSelects the proper thermodynamic cycle, e.g. open versus closedDelivers:
Engine operating parameters (Isp, thrust, mass, etc.)Engine component parameters (temperatures, pressures, mass flow, flow areas, etc.)Concept trade-offs
Types of Engine or Power CyclesUp to now, only four cycles have been developed and flown:
Pressure-fed -, gasgenerator -, expander -, staged combustion cycleThe gasgenerator cycle was the first in use
One further cycle is currently part of a US R&T demonstration program (IPD)Full flow staged combustion cycle (FFSCC)
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 12
Pressure-Fed Cycle
Design Examples for Liquid Rocket Engines
Gagenerator (GG) Cycle
No pumps/turbinesLow thrustPressurized tanks feed thepropellants into the main chamberSimpler engine design
Open cycleMedium to high thrustA small amount of the propellant is burnedseparately in the GG to drive the turbines Turbine drive gas is pumped over boardand not routed back to the main injector
Cycles of Flight Engines
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 13
Expander or Bleed Cycle
Design Examples for Liquid Rocket Engines
Staged Combustion Cycle
Closed or open (bleed) cycleHigh performance/medium thrustNo gasgenerator/preburnerAll or a portion (bleed) of cooling channel gas is used to driveturbines
Closed cycleMedium to high performance/thrustPropellant is burned in two stages:preburner and main chamberAll propellant is mixed and burned inthe main combustion chamber (MCC)
Cycles of Flight Engines
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 14
Cycles of Flight EnginesFull Flow Staged Combustion Cycle
Synthesis/ConclusionEurope combined the high energetic propellant (Lox/H2) with the medium efficient gasgenerator cycleUS (SSME), Russia (RD-0120) and Japan (LE-7A) have already applied the high energetic Lox/H2 to the high efficient staged combustion cycleThe technology step combining Lox/H2 with staged combustion might be the next generation engine in Europe
Design Examples for Liquid Rocket Engines
Closed cycleHigh performance/medium thrustAll propellants pass the turbinesLower turbine gas temperature by using a full flow cycleLonger engine lifeChallenge: Oxidizer-rich preburnerMost efficient rocket engine cycle
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 15
Solid Rocket Propellant- and Motor-Classification: conventional
Motor/grain shape: >Conventionalpropellants:v
Cylinder grain with internal star cross section (below)
Spherical Solid Rocket Motor (Historic Black Arrow Waxwing)
Storable„conven-tional“AP/HTPB/Algrain (right):
Endburner:Very highcharge density(good for HEDM!)
Spherical kick-stage motor, in-space applications (above)
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems
Solid Rocket Propellant- and Motor-Classification: cryogenic
16
CSP use frozen liquids, e.g. based on solid hydr. peroxide or oxygen with polymers.
Grain design: >Cryogenic solid propellants CSP V
Modular cylinder grain: alternating stack of ox.-and fu-moduls; igniter, gasgenerator (below)
Quasi homogeneous cylindrical sponge grain
Modular end-burners with Rod-in-matrix, tube bundle and concentric layer design (right)
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 17
(MT) Design Examples for Solid Rocket Motors
Small In-line /Strap-on Booster
size: Ø up to 1,6 m
monolithic steel (roll-and-weld) or CFRP cases (filament wound)
Performance factorssteel: 2,7- 8,5 kmCFRP: up to 14 km
Solid propellant stages size: up to 350 to propellant
Ø up to 3,5 msegmented cases high strength steel or CFRPthrust vector controlled
In-Orbit MotorsUsed for: position / apogee motorsSize: Ø 4 inch – 1300 mm
monolithic casingMaterial: steel and Titanium, also
C- and Aramide-fibresPressure:up to 6 MPa
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 18
(MT) Design Examples for Solid Propulsion Stage Structures
Common features
Propellant
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 19
(MT) Design Examples for Solid Propulsion Stage Structures
steel segments welded from individual cylinders and domes
Clevis-Tang Intersegment Joint retaining „nose“ againstopening under pressureO-ring sealing
Composite casings
VEGA P80 at AVIO
Ariane 5 MPS segment S1:
Infiltration technique
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 20
Load Introduction Structure – Ariane 5 Front Skirt
The EPC Front Skirt (JAVE-C) is located at the top of the cryogenic main stage (EPC) of the Ariane 5 launcher and transmits the thrust of the solid boosters into the central body of the launcher and equalizes it regarding payload compatibility
Diameter 5 400 mmTotal height 3 288 mmMass 1 785 kgLoad capacity 6 000 kNMaterial Aluminum alloy,
CFRPThermal protection PROSIAL®
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 21
Large Liquid Propellant Tank Structures – Ariane EPC Domes
• Comparison with gore panel methodadvantages of concave spin-forming:
– less parts to manufacture reduced costs, logistics easier– T8 of complete dome
plate welds exhibit T8 condition, too weight saving
Spin-formed dome
Dome with gore panel method
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 22
Large Liquid Propellant Tank Structures – Domes for H II-A
MT Aerospace AG manufactures for Mitsubishi Heavy Industries the1st stage and LRB tank bulkheads of Japans launch vehicle H-IIA. The elliptical bulkheads are spinformed of one Al 2219 plate to final T8 temper. MT's spinforming technique leads to tank bulkheads with less weight, better material properties and lower cost than the conventional method used for H-II.
Diameter 3 860 mm (12.7 ft) Height 738 mm (29.1 in)Material Al 2219 T8 Propellants LOX/LH2
Mass 230 kg (507.1 lb) (LOX) Pressure 4.3 bar (62.4 PSI) (LOX)180 kg (396.8 lb) (LH2) 3.4 bar (49.1 PSI)
NA
SD
A
Wie
sem
ann
04
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 23
CMC Elements of Re-Entry Vehicles - X38 and CRV Heritage
wing leading edge nose cap
„chin panel“
high temp. bearing
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 24
CMC Elements for Re-Entry Vehicles - X38 and CRV Heritage
XPERT hot metal TPS configuration with ODS metal cone, CMC nose and flaps (Image Courtesy Dutch Space - EADS Astrium)
X38 Hypervelocity re-enty.(Img.:NASA)
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems
Design Examples of Hybrid Rocket Motors
• SpaceDev SS1 Hybrid Motor Development 2003 / 2004(Poway, Cal.USA)
25
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 26
(AI / ASTRIUM) Design Examples of Hybrid Rocket Motors
(above) SpaceDev Hybrid Propulsion Module Test Facility / (right) “Dream Chaser” SD Hybrid Suborbital Plane (Img. Courtesy SpaceDev)
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems 27
.
• Chemical rocket propellants will be used for the next 50 years + !!• Specific energy of available propellants will increase tenfold within
the next 20 years (Isp triples)• Environmental benignity will be the most important design driver of
new propulsion systems within 5 years• Liquid Rocket Engines will be used where-ever throttling and
reusibility are prime requests• Solid Rocket Motors will go cryogenic within 15 - 20 years (HEDM)• Hybrid Rocket Motors will continue to be used wherever their chaotic
combustion is not a concern• Structures of liquid propulsion stages will see very high degrees of
integration• Solid Propellant stage structures will need adaptation to reusibility.
Propulsion, Structures and Subsystems - Results and facts
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems
Propulsion, Structures and Subsystems - Results and facts
Subsystems still to be investigated:• Integrated solid propulsion for winged vehicles• Replaceable units for propulsion, in particular ORPUs • HEDM additive production and application• Soft boundary layer (low noise) HEDM rocket nozzles• Lunar infrastructure (+ transportation): design to specific structures• ....
28
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems
Summary and Outlook
Summary and Outlook (1)• Annual launch numbers of stages with LOX-LH2 / Solids / LOX-Kero
/ NTO-Hydr. = 1 : 3,14 : 3,22 : 3,36• Environmental loads caused by space traffic are negligible
compared with aircraft emissions, but are unique above ~12km • Propellant handling- and environmental risks can be evaluated by a
characteristic hazard number (TEHF)• Liquid propulsion is a mature technology but still able to see some
further improvements towards advanced combustion cycles• Conventional storable quasi-homogeneous solid propellant grains
will be replaced by cryogenic modular ones in all missions without long term storability requirement
29
DGLR / CEAS European Air and Space Conference 2007
DGLR Fachausschuss Raumtransportsysteme S4.1 / Propulsion, Structures and Subsystems
Summary and Outlook
Summary and Outlook (2)
• Ceramic Matrix Composites are a key technology for hot re-entry structures
• Advanced production methods can reduce costs (e.g.: spin formed tank domes)
• Hybrid propulsion is fashionable but will never make it without active regression rate control
• One last time: high thrust propulsion will remain chemical for all foreseeable future
Thats all folks! Thank you for your attention!
30