Dokumentname > 23.11.2004

German Aerospace Center

Folie 2Institute of Aerodynamics and Flow Technology

Department Spacecraft

TAU Extensions for Hypersonic Reacting FlowVolker Hannemann

v=7.8 km/sh=200 km

v=11.0 km/sh=200 – ∞ km

v=10.2 km/sh=200 – 36000 km

• Motivation

• Current state of modeling

• Some applications

• Near future work

Folie 3Institute of Aerodynamics and Flow Technology

Department Spacecraft

Reentry in Earth atmosphere

Manoeuvering spacecraft+ high Mach numbers+ low densities+ high temperatures, TPS+ Blackout

Manoeuvering spacecraft+ high Mach numbers+ low densities+ high temperatures, TPS+ Blackout

Folie 4Institute of Aerodynamics and Flow Technology

Department Spacecraft

Perfect Gas Extensions

• High Mach numberStrong shocks: Carbuncle, Multigrid, …

• Low densitiesStrong expansions: near vacuum states

• High temperaturesSurface temperature predictionSurface radiationActive cooling: porous media, ablation

Folie 5Institute of Aerodynamics and Flow Technology

Department Spacecraft

High Temperature Effects

• Vibration of molecules

Behind a strong bow shock occur:

Behind a strong bow shock occur:

+

• Chemical reactions: dissociation / recombination

hν

• Electronic excitation and radiation

• Catalytic surfaces

• Ionisation

Folie 6Institute of Aerodynamics and Flow Technology

Department Spacecraft

Equilibrium Extensions

• Two state variables determine all other variablesp(rho, e), T(rho, e), Ys(rho, e), …

• Transport properties depend on T and YsEffective thermal conductivity models diffusion

• Current developmentsImproved models for internal energiesSmaller curve fits (memory)Better models for transport coefficients

Folie 7Institute of Aerodynamics and Flow Technology

Department Spacecraft

High Temperature Effects

• Vibration of molecules

Behind a strong bow shock occur:

Behind a strong bow shock occur:

+

• Chemical reactions: dissociation / recombination

hν

• Electronic excitation and radiation

• Catalytic surfaces

• Ionisation

Folie 8Institute of Aerodynamics and Flow Technology

Department Spacecraft

Non Equilibrium Extensions

• Additional balance equationsFor partial densities: chemical source termsFor vibrational energies: relaxation source terms

• Transport propertiesSpecies curve fits + mixing rules (Wilke, Yos)

• Diffusion termsFick’s law – binary diffusion modelCatalytic surfaces

Folie 9Institute of Aerodynamics and Flow Technology

Department Spacecraft

Chem.+ therm. non equilibrium

Chem. non equilibrium + therm. equilibrium

Chem. + therm. equilibrium

X-38, Shuttle

Apollo

10% 10% 10% 10%90% 90% 90%

Vibr

atio

n

O2-

diss

ocia

tion

N2-

diss

ocia

tion

Ioni

satio

n

Velocity-Altitude Map Free molecularregime

Tran

sien

tC

ontin

uous

regi

me

laminar

turbulent

Concorde

Folie 10Institute of Aerodynamics and Flow Technology

Department Spacecraft

IMENS -- Test-Model

Flap model

Folie 11Institute of Aerodynamics and Flow Technology

Department Spacecraft

Anströmung im Windkanal

Folie 12Institute of Aerodynamics and Flow Technology

Department Spacecraft

Folie 13Institute of Aerodynamics and Flow Technology

Department Spacecraft

Results of body-flap model 1

Fig. 13: Surface temperature and streamlinesof coupled CFD-CSM solution

Fig. 12: Surface temperature and stream-lines of radiation equilibrium CFD-solution

Folie 14Institute of Aerodynamics and Flow Technology

Department Spacecraft

TAU –Equilibrium: Shock reflection in HEG, num. Schlieren picture

Particle stopper

Shock tube end wall

Nozzle throat

Folie 15Institute of Aerodynamics and Flow Technology

Department Spacecraft

Near Future Work

• Supersonic turbulent hydrogen combustionScramjet investigations

• Earth reentry from planetary missionsIonization

• Other atmospheresMars: CO2, …Titan: CH4, …

• Improved thermal relaxation

Dokumentname > 23.11.2004

Thank Youfor your attention!