Introduction Correlations & High-Fidelity Sims. Case Studies Atmospheric Entry Plasmas F´ ısica dos Plasmas M´ ario Lino da Silva, Bruno Lopez, Vasco Guerra and Jorge Loureiro Instituto de Plasmas e Fus˜ ao Nuclear Instituto Superior T´ ecnico, Lisboa, Portugal March 10, 2014 M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
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Atmospheric Entry Plasmas - ULisboa · (photodissociation, photoionization, photodetachment) and free-free (Bremstrahlung) transitions bound-bound transitions include atomic, diatomic
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IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Atmospheric Entry PlasmasFısica dos Plasmas
Mario Lino da Silva, Bruno Lopez, Vasco Guerra and JorgeLoureiro
Instituto de Plasmas e Fusao NuclearInstituto Superior Tecnico, Lisboa, Portugal
March 10, 2014
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
What are Atmospheric (Re)-Entry Plasmas
Typical Earth reentry profile Spacecraft entry in Mars Atmosphere (Artist Illustration)
Formation of a strong shockwave upstream of a spacecraft crossingthe upper atmospheric layers at hypersonic speeds.
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Shockwaves as Plasma Precursors
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Comparison Between Entry and Laboratory DischargePlasmas
Reentry Plasma
1/2mv2 ' 7/2kBTtr
v = [7− 10km/s]⇒Ttr = [25, 000K− 60, 000K]
Ttr � Tvib
Gas Discharge Plasma
Tel = 1− 3eV
V–e processes dominant
Ttr � Tvib
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Plasma Radiation as a Spacecraft Design Driver
Radiative heating can be a major design driver forlarge or high-speed (≥ 10km/s) entry vehicles
For lower entry speeds, radiative heating maymandate additional thermal protections (e.g. baseheating for Martian entries)
Convective heating mostly depends on groundspecies, radiative heating depends on excited species.Larger uncertainties
Accounting for an additional spectral dimension withgrids with over 106 points. Very computationallyintensive CFRD simulations.
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Main Drivers
Do we need to take radiation into account?
Optically thin or thick?
Coupling between flow and radiation?
Equilibrium or non-equilibrium radiation?
Selection of an appropriate radiative database
Other issues (precursor, photo-chemistry, photo-ionisationprocesses)
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Aerothermodynamics of Entry Vehicles
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Aerothermodynamics of Entry Vehicles
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
10−3 < Γ < 10−2: radiation is important but coupling isnot necessary
Γ > 10−2: coupling of the radiation to the flowfield isnecessary
The absorption coefficient is related to the opticaltransmissivity such that T = exp(−αδ). Transmissivitygoes from 100% (optically thin) to 0% (optically thick).
aknown as the Rosseland limit
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
“Collection” of lines which correspond to the overall quantum-allowedradiative transitions between the internal levels of an atom/molecule.
Selection rules define the quantum-allowed transitions, which must respectangular and spin momentum conservation for atoms and molecules.
Three key parameters:1) Line position considering Planck’s Law: ν = Eu − El/hc ;2) Line intensity: Iν = NuAul∆Eul ;3) Line profile: F (ν − nu0), Voigt (sum of a Lorentz & Gaussian profile).
Radiative spectra obtained through the superposition of these overall lines.
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
“Collection” of lines which correspond to the overall quantum-allowedradiative transitions between the internal levels of an atom/molecule.
Selection rules define the quantum-allowed transitions, which must respectangular and spin momentum conservation for atoms and molecules.
Three key parameters:1) Line position considering Planck’s Law: ν = Eu − El/hc ;2) Line intensity: Iν = NuAul∆Eul ;3) Line profile: F (ν − nu0), Voigt (sum of a Lorentz & Gaussian profile).
Radiative spectra obtained through the superposition of these overall lines.
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
“Collection” of lines which correspond to the overall quantum-allowedradiative transitions between the internal levels of an atom/molecule.
Selection rules define the quantum-allowed transitions, which must respectangular and spin momentum conservation for atoms and molecules.
Three key parameters:1) Line position considering Planck’s Law: ν = Eu − El/hc ;2) Line intensity: Iν = NuAul∆Eul ;3) Line profile: F (ν − nu0), Voigt (sum of a Lorentz & Gaussian profile).
Radiative spectra obtained through the superposition of these overall lines.
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
“Collection” of lines which correspond to the overall quantum-allowedradiative transitions between the internal levels of an atom/molecule.
Selection rules define the quantum-allowed transitions, which must respectangular and spin momentum conservation for atoms and molecules.
Three key parameters:1) Line position considering Planck’s Law: ν = Eu − El/hc ;2) Line intensity: Iν = NuAul∆Eul ;3) Line profile: F (ν − nu0), Voigt (sum of a Lorentz & Gaussian profile).
Radiative spectra obtained through the superposition of these overall lines.
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
Validation of Aerothermal databases against simpler (1D,
time-dependent) representative flow conditions
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Coupled CFD-Radiative Simulations of Huygens Entry
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Influence of Radiation and Radiation Coupling
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Mars EXPRESS Observation of the PHOENIX Entry
ESA Mars EXPRESS Orbiterprovided support for PHOENIX2008 Mars Entry
Mars EXPRESS TrackedPHOENIX Entry with his onboardinstrumentation (First Attempt attracking an Entry from anOnboard Satellite).
CFRD simulations prior to entry predicted the IR trail to be the mostemissive.
SPICAM VUV Camera and HRSC Visible Camera tracked the Entry.IR Fourier Spectrometer could not be turned on due to power budgetconstraints.
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
CFRD Simulations of PHOENIX Entry
PHOENIX Temperature Profiles, t=203s Sample spectrum of the PHOENIX Plume
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
HRSC Observation in # 5647 during Phoenix EDL : Nadir Context of Limb
° ° SC /
SOWG 38, ESAC, Villafranca: HRSC Future Planning Hoffmann and Hauber 04 June 2008
195° E, 81.5° N: HRSC ND, spatial resolution 12.5 m/pixel, image width 18 km
HRSC Observation in # 5647 during Phoenix EDL : Pointing during 144 SRC Frames
f f f
SOWG 38, ESAC, Villafranca: HRSC Future Planning Hoffmann and Hauber 04 June 2008
Phoenix always in center of frame based on latest available Kernel from 25 May
HRSC in # 5647 during Phoenix EDL : SRC 076
Uppermost limb haze layers (detached haze y (layer) enter FOV
SOWG 38, ESAC, Villafranca: HRSC Future Planning Hoffmann and Hauber 04 June 2008
HRSC in # 5647 during Phoenix EDL : SRC 096
Upper limb within FOV
SOWG 38, ESAC, Villafranca: HRSC Future Planning Hoffmann and Hauber 04 June 2008
HRSC in # 5647 during Phoenix EDL : SRC 116
Optically thick limb at edge of FOVg
•No hints for flash or brightening
•Pointing and timing seem to be correct
Phoenix not detected:•Upper limit for energy releaserelease
•Consistent with continuous telemetry link
SOWG 38, ESAC, Villafranca: HRSC Future Planning Hoffmann and Hauber 04 June 2008
ESA UNCLASSIFIED – For Official Use
ExoMars Programme: two missions launched in 2016 and 2018.• The 2016 mission consists of the Trace Gas Orbiter (TGO) and the EDL Demonstrator Module (EDM)• The 2018 mission consists of the Rover, accommodated inside a Descent Module (DM) and carried
to Mars by a Carrier Module (CM)• Large international cooperation with Roscosmos and some contributions from NASA
Comparison of the overall temperature dependent radiative power of CO2 IR radiation (red) and for the other
radiative systems (black) for an atmospheric pressure, Martian-type CO2–N2 plasma. Comparison is carried for the
SPARTAN code database (full lines) and the EM2C database (dotted lines).
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Example of a Ray Departing from the Afterbody Plume;PH (1/2)
103
104
105
10−15
10−10
10−5
100
Wavelength (A)
Inte
nsity
(W
/m2 /c
m−
1 )
Intensity at ray departureIntensity at ray arrival
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Example of a Ray Departing from the Afterbody Plume;PH (2/2)
4.17 4.1705 4.171 4.1715 4.172 4.1725
x 104
10−1
100
101
Wavelength (A)
Inte
nsity
(W
/m2 /c
m−
1 )
Intensity at ray departureIntensity at ray arrival
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Comparison of Stagnation Streamline and BackcoverShoulder Spectra; PH
VUV-Visible radiation higher for the stagnation streamlinepoints
For both points, CO2 radiation spectral intensity is severalorders of magnitude above Visible-VUV radiation
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Contribution of Radiative Fluxes above 1µm to the OverallRadiative Power; Large Spacecraft Configuration
0 5 10 15 20 25 30 35 40 45 5099.8
99.82
99.84
99.86
99.88
99.9
99.92
99.94
99.96
99.98
100
Wall Point
IR R
adia
tion
Con
trib
utio
n (%
)
PHPPP28P23SHA
Values for the smaller spacecraft configuration are similar. Other studies in the scope
of the ESA TC3 testcase confirm such findings for CO2–N2 mixtures (CN and C2
radiation less than 3% overall in the stagnation streamline point.
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
The ESTHER Shock-Tube Project
European Shock Tube for High Enthalpy Research
European Space Agency project
International consortium, led by Instituto Superior Tecnico, for thedevelopment and comissioning of a shock-tube facility for planetaryexploration research in the high speed regime
Consortium partners include:
Fluid Gravity Eng. (Ermsworth, UK),Universite de Provence (Marseille, France),Ingenieurie Systemes Avances (Bordeaux, France),Moscow Institute for Physics and Technology (Moscow, Russia),Instituto de Soldadura e Qualidade (Lisboa, Portugal),Shock-Waves Laboratory (Aachen, Germany),University of Manchester (Manchester, UK),Universite Blaise Pascal (Clermont–Ferrand, France),Universite Paris VI (Paris, France)
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Shock-Tube Characteristics
Facility capable of reproducing shock waves for gas mixtures simulatingthe atmosphere of Earth, Mars and Venus (CO2–N2), Titan (N2–CH4).
High pressure reached in the driver section through the deflagration of ahigh-pressure H2–O2 mixture. This allows a quick-rise in pressure,enabling 3–4 shots per day, but needs special precautions related to thepresence of explosive gases.
Shock velocities of v '4–12km/s, allowing the simulation of orbital (slowspeed) and interplanetary superorbital entry plasma flows.
High-speed automated diagnostics (MHz) for control, acquisition, andcollecting light emitted by the plasma.
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Shock-Tube Design (1/4)
High Pressure Driver Section
600 bar maxium working pressure
900 bar design limit
Internal diameter 200mm
Outer diameter 360mm
Internal length 1.5m
Nominal mixture70%He,20%H2,10%O2
Initial pressure 10 to 50 bar
High pressure ignition and safetysystem
Combustion gas preparation systemand induction system includingmixing, storage, valves, probes andgauges
Gasket system with rupture pressures60 to 600 bar
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Shock-Tube Design (2/4)
Compression Tube (or second stage)
Internal diameter 130mm
Outer diameter 150mm, length 6.5m
Initial pressure 0.1-0.5 bar (optimized for each run)
Gasket system with rupture pressures 5 to 25 bar
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Shock-Tube Design (3/4)
Working Section
Internal diameter: 80mm
outer diameter: 150mm
length from diaphragm to window:4m
total internal length to the dumptank: 5.4m
Initial pressure 10 to 1000Pa
Pumping system: minimum pressureof 10-8 mbar during cleaningprocedures, ensure known initial testgas composition.
Working gas preparation andinduction system including probesand gauges.
Windows (UV/VUV transparent)and window mounting system.
Shock speed / pressure measurementsystem.
Diaphragm to dump tankM. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
IntroductionCorrelations & High-Fidelity Sims.
Case Studies
Titan Entry: HuygensMars Entry: PHOENIX and EXOMARSThe ESTHER Shock Tube
Shock-Tube Design (4/4)
Dump Tank
Post window section lead in tube to dump tank
Pressure range, vacuum to 2bar pressure post shot.
Diameter: 1 m
Length: 3 m
M. Lino da Silva, B. Lopez, V. Guerra and J. Loureiro, IPFN Reentry Plasmas
Outside view of the laboratory and view of the experimental hall
ESTHER shock-tube
Hypersonic Plasmas LaboratoryEuropean Shock-Tube for High Enthalphy Research
Shock-Tube: A facility for reproducing the conditions of an atmospheric entry Support to planetary exploration missions and meteoroids planetary protection research 2M€ total funding, 1,75M€ funding from the European Space Agency First facility of its class to be built in the last 30 years in Europe, located at IST-IPFN World class facility capable of reaching superorbital shock-speeds in excess of 10km/s