Heat-shield for Extreme Entry Environment (HEEET) !
A Game Changing Thermal Protection System !
for Saturn and Uranus Probe Missions !
Presented by: E. Venkatapathy, !
Advanced EDL Materials Project Manager / Game Changing Development Program!
Chief Technologist, Entry System and Technologies Division !
NASA Ames Research Center!
!
HEEET Project Manager: D. Ellerby!
Leads: M. Stackpoole, K. Peterson and P. Gage!
Team Members: A. Beerman, M. Blosser, R. Chinnapongse, R.Dillman, !
J. Feldman, M. Gasch, M. Munk, D. Prabhu and C. Poteet !
OPAG Meeting, January 13-14, Tuscon, AZ!
OBJECTIVES!
Ø  Enable!
q  Discovery and New Frontier proposal teams to have a relatively mature TPS
solution that will pass TMCO evaluation !
q  Development of heat-shield technology (HEEET) by 2016 for infusion into
future robotic in situ-science missions. !
Ø  Engage!
q  The OPAG and potential PIs/proposing organizations so that they are both
stakeholders and partners in the technology maturation phase!
Ø  Ensure!
q  User requirements are balanced by developmental risk and cost!
q  The user community understands infusion challenges beyond technology
maturation!
Ø  Inform!
q  The community on current accomplishments and future plans of HEEET!
2!
ENABLING OUTER PLANET MISSIONS IN THE COMING DECADES!
Ø  Saturn (and Uranus) in situ science mission(s)!
q  Missions studied prior to and in support of Decadal Survey !
u  Probes based on Galileo Design (rigid aeroshell with TPS)!
q  Revive heritage carbon phenolic, or!
q  Develop advanced TPS that is superior in performance to HCP and
sustainable in the longer term!
Current ablative TPS State of the Art !
3!
ENABLING OUTER PLANET MISSIONS IN THE COMING DECADES!
Ø  Saturn (and Uranus) in situ science mission(s)!
q  Missions studied prior to and in support of Decadal Survey !
u  Probes based on Galileo Design (rigid aeroshell with TPS)!
q  Revive heritage carbon phenolic, or!
q  Develop advanced TPS that is superior in performance to HCP and
sustainable in the longer term!
Ø  Under 3-D Woven TPS Effort!
q  Combining the advance weaving techniques and resin infusion, we were
able to create a family of ablative TPS!
q  Heat-shield for extreme entry environment technology (HEEET)!
4!
BACKGROUND: WOVEN TPS!
Ø  HEEET - 3-D Woven TPS Family!
q  Woven TPS: An approach to the design and manufacturing of abla;ve TPS by the combina;on of 3-­‐D weaving that allows precise placement of fibers in an op;mized manner and resin infusion if needed Ø  In FY’12, established viability of the 3-­‐D Woven TPS. q  Explored the “10,000” manufacturing ways of formulaKng a TPS q  AblaKve TPS opKons, dry-­‐woven as well as resin infused systems, ranged in density from (0.3 g/cc – 1.4 g/cc) in overall density q  Highlighted the Woven TPS potenKal for meeKng the mission needs of Venus, Saturn and High-­‐speed Sample Return Missions (VEXAG 2012 & OPAG 2013) OPAG (& VEXAG) recommendaKon to SMD-­‐PSD & the resulKng advocacy and support by SMD-­‐PSD were criKcal in securing 3-­‐year project currently funded by STMD/Game Changing Development Program
5!
FYʼ13 ACCOMPLISHMENTS!
Ø  Manufactured and Tested a
variety of Woven TPS!
q  Density range from PICA to
heritage CP!
Density (g/cc)
1.6
1.4
Fully
Dense
Fully Dense
1.2 Carbon
Phenolic
3-D Woven
1.0
(different resins)
0.8
Dual Layer
Carbon
Phenolic
0.6
Dry Woven
Carbon
Phenolic
AVCOAT 3-D Woven CP
0.4
(low phenolic infusion)
0.2
KEY
Heritage TPS
PICA
Woven TPS
6!
2017!
3-D Woven Multifunctional !
Ablative TPS (3D-MAT)!
2022+!
A BRIEF HISTORY WOVEN TPS TECHNOLOGY: WOVEN TPS TECHNOLOGY MATURATION AND MISSION INSERTION!
2016+!
Oct, 2013!
June, 2012!
Jan. 2012!
Tech. Maturation to enable
Venus, Saturn and outer
planets missions !
Sept. 2016!
Heat-shield for Extreme Entry !
Environment Technology (HEEET) !
Woven TPS
GCT BAA!
April 2011!
2020 - 2022!
Enabling Orion with Lunar !
Capable Compression Pad!
Robust Heat-shield for
Human Missions !
(Future Potential)!
7!
FYʼ13 ACCOMPLISHMENTS!
Ø  Manufactured and Tested a
variety of Woven TPS!
Ø  Down-selected a single
architecture.!
q  Based on testing, analysis,
performance characteristics,
developmental risk and cost!
Recession Resistant Layer!
Insulating, Lower !
Density Layer!
Bonded Structure!
8!
FYʼ13 ACCOMPLISHMENTS!
Ø  Manufactured and Tested a
variety of Woven TPS!
Ø  Down-selected a single
architecture.!
Ø  Defining TRL 5/6 with community/
user input and buy-in!
q  Held a workshop ( 95+
participants)!
q  Common capability to meet
Venus, Saturn and other
destinations defined with the help
of and understanding of the
participants!
q  Capability requirements
verification defines the TRL
maturity!
!
Woven TPS !
Technology!
Human !
Missions!
Venus!
Ground Test !
Capability!
Saturn!
High-speed !
Sample Return!
9!
FYʼ13 ACCOMPLISHMENTS!
Ø  Manufactured and Tested a
variety of Woven TPS!
Ø  Down-selected a single
architecture.!
Ø  Defining TRL 5/6 with community/
user input!
Ø  Developed 3-year technology
maturation project plan!
Ø  Secured funding and approval
from STMD for the technology
maturation efforts ( FYʼ14 – FYʼ16)!
Ø  User Agreement under
development!
Goal: Deliver a TRL 5/6 !
Heat-shield Technology in 3 years!
10!
SATURN Probe Design Space!
Entry Corridor : Equatorial and a 600 N/S !
Entry Flight Path Angles: -80 and -190!
Mass = 250 kg; Probe Dia. = 1 m!
600 N/S
Equat.!
Stag. Heat Flux, kW/cm2!
Steeper Entry (-19°) !
Shallower Entry ( -8°)!
600 N/S!
Equatorial!
Pressure, atm.!
SATURN Probe Design Space & Ground Test Facility Conditions !
Entry Corridor : Equatorial and a 600 N/S !
Entry Flight Path Angles: -80 and -190!
Mass = 250 kg; Probe Dia. = 1 m!
IHF – 3” Nozzle!
Pressure,
!
1”atm.!
Iso-Q Test Article!
600 N/S
Equat.!
Steeper Entry (-19°) !
Shallower Entry ( -8°)!
Stag. Heat Flux, kW/cm2!
FYʼ13 Arc Jet Testing !
IHF - 6 inch Nozzle!
IHF 3” Nozzle!
1” Flat Face Article!
AEDC (Wedge)!
Pressure, atm.!
ARC JET TEST RESULTS – TWO LAYER SYSTEM!
•  Both acreage and preliminary seam concepts tested at three relevant conditions.!
•  No failure observed in these or other relevant arc jet tests to-date. !
•  HEEET appears to be very robust compared to carbon phenolic. !
13!
SATURN PROBE AREAL MASS COMPARISONS !
Equatorial @ -90!
Equatorial @ -190!
Lat. 600 @ -90!
Lat. 600 @ -190!
•  Areal mass of the 2-layer system has the potenital for ~ 40% mass savings
compared to that of heritage Carbon Phenolic!
•  Un-margined; preliminary estimate with very limited property data!
•  Carbon Phenolic heat-shield mass estimates ~ 50% of the entry mass!
•  Performance combined with anticipated robustness makes HEEET an
exceptional TPS!
14!
SATURN PROBE THICKNESS COMPARISONS !
1.60!
Recession Layer!
1.40!
Insulative Layer!
Thickness, in!
1.20!
1.00!
0.80!
0.60!
0.40!
0.20!
0.00!
Weave Weave Carbon
#1!
#3! Phenolic!
Weave Weave Carbon
#1!
#3! Phenolic!
Weave Weave Carbon
#1!
#3! Phenolic!
Weave Weave Carbon
#1!
#3! Phenolic!
G8H90!@ -90!
Equatorial
Equatorial
@ -190!
G19H90!
600 G8H30!
Lat. @ -90!
600 G19H30!
Lat. @ -190!
•  Un-margined HEEET thickness ( 0.80” – 1.4”)!
• 
~20% thicker compared to heritage carbon phenolic!
• 
Thickness impacts cost, schedule and is a risk drivers for technology maturation. !
• 
Question to the Saturn Community: !
• 
Equatorial and steeper entry will result in lowest thickness and areal mass!
•  Are there scientific rationale for high latitude? How high? !
• 
Are there Con Ops requirements that dictate entry angle? Steeper or shallower? !
15!
URANUS MISSION DESIGN COMPARISONS
AREAL DENSITY COMPARISONS!
•  2-layer system can result in potential ~ 50% mass savings compared to Carbon
Phenolic for the range of entry configurations considered for Uranus small probe(s)!
•  Un-margined and based on very limited property data!
•  Simulation on a flank location comparison is very similar in that the zero-margin areal
density is ~ 50% as that of Carbon Phenolic
16!
URANUS MISSION DESIGN COMPARISONS
THICKNESS COMPARISONS – STAGNATION POINT!
1.2
Recession Layer
1
Insulative Layer
Thickness, in
0.8
0.6
0.4
0.2
0
HEEET #1 HEEET #3 Carbon
Phenolic
HEEET #1 HEEET #3 Carbon
Phenolic
HEEET #1 HEEET #3 Carbon
Phenolic
Entry Angle: 68 deg
Entry Angle: 42 deg
Entry Angle: 24 deg
•  HEEET thickness is comparable to that of Carbon Phenolic for the range of entry
configurations considered for Uranus small probe(s)
•  Simulation on a flank location comparison is very similar in that the zero-margin
thickness is comparable to that of Carbon Phenolic
•  Comparing Saturn and Uranus Probes, Saturn is the driver for thickness
•  Are there Uranus specific drivers for a technology maturation effort – TBD ?
•  We need to engage with the Science and mission design communities as the
opportunity is here and now for the TPS technology
TECHNOLOGY MATURATION CHALLENGES!
Ø  System/Manufacturing q  Molding flat panels q  Seams q  Resin Infusion at scale Ø  IntegraKon q  Aeroshell sub-­‐structure and with backshell Ø  Flight System design tools development and verificaKon q  Thermal response model is an example of design tool needed q  Engineering Test Unit –  ~(1.0m – 1.5m) Base Diameter, 45° Sphere Cone –  Design will be proven at a smaller scale that is applicable for larger scale –  Smaller likely compared to Venus lander missions such as VITaL –  Integrated “Kled” design Successful ETU design, build and testing = TRL 5/6
(for full scale Venus, Saturn and higher speed sample return missions)
18!
CONCLUDING REMARKS!
Ø  FYʼ13 has been a great year!
q  Successful testing, analysis and planning along with community advocacy
resulted in HEEET project becoming a funded, 3-year tech. mat. effort!
Ø  Current project plan is aggressive!
q  Numerous tech maturation challenges need to be overcome!
q  Dialogue between STMD and SMD-PSD!
q  NASA (STMD) developed technology infusion in a SMD competed mission !
Ø  HEEET is a game changer and applicable to a wide range of missions !
q  Critical for near, mid and longer term Science missions as well as longer term Human
missions !
u  Saturn and Venus for the next New Frontier!
u  Uranus – we need to work with the Uranus community!
Ø  Continued community engagement is a must: !
q  Through OPAG-VEXAG-other Ags. – Plan to report progress (annual basis) !
q  Workshop, targeted towards near proposal community (Discovery and New
Frontier), on an annual basis is planned (at a minimum)!
q  Dialogue between HEEET and proposing organizations/proposal teams on
an on-going and as needed basis is underway!
19!
ACKNOWLEDGEMENTS!
!
Ø  Support and commitment of STMD, GCDP within STMD and SMDPSD allowed us to mature our plans in FYʼ13. We are very grateful.!
Ø  We are grateful to OPAG and look forward to continued advocacy
for HEEET!
Ø  Bally Ribbon Mills, our partner in this effort, has shown extraordinary
commitment and willingness to explore the myriad of possibilities.!
20!