Download - A b s t r a c t # 1 6 6 6 - ISRU Info
2/27/2017 CIM | TPMS |
https://www.cim.org/en/TPMSEvent/Chair/ChairAbstractPool.aspx 1/1
Abstract #1666
English
The latest from MOXIE
Essential subsystems of the Mars Oxygen ISRU Experiment (MOXIE) on NASA’s Mars 2020 mission have passed their Critical Design Review, and the project isbeginning a flight build stage that will culminate in delivery of flight hardware in late 2018. Also being delivered to the MOXIE Science Team is an Engineering Model,equivalent in form, fit, and function to the flight hardware, that will support Mars 2020 mission operations and subsequent extensions of the MOXIE flightdemonstration (for example, tests of long duration operation). As a scale model of a future oxygen production facility on Mars, MOXIE will generate a minimum of 6g/hr high purity oxygen from the Martian atmosphere in at least 15 separate runs, sampling different environmental conditions on Mars, in the 2.5 years followinglanding of the Mars 2020 rover in February, 2021. The presentation will review the MOXIE scroll pump for CO2 collection and compression, the solid oxideelectrolysis system and its packaging for CO2 conversion to O2, the monitoring and control subsystem, and the expectations for operation on Mars.
French
No abstract title in French
No French resume
Author(s) and CoAuthor(s)
Dr. Michael H Hecht(UnknownTitle)MIT Haystack Observatory
N/A The MOXIE Team(UnknownTitle)MIT Haystack Observatory
4/26/2017 CIM | TPMS |
https://www.cim.org/en/TPMSEvent/Chair/ChairAbstractPool.aspx 1/2
Profile of Dr. Michael Hecht
General
Email(s): [email protected] Position:
Preferred Language: [Language not defined]
Addresses
Biographies
Collaborators
Business Home
Biography submitted with the abstract
Michael Hecht is the Associate Director for Research Management at the MIT Haystack Observatory, and Principal Investigator for the MOXIE payload on NASA’s Mars 2020 Rover mission.Previously, he was a Senior Research Scientist at JPL, where he served as PI and Instrument Manager for the MECA instrument on the Phoenix Mars Scout mission, a soil analysis suite forinvestigating wet chemistry, microscopy, and thermophysical properties, which was originally developed in support of the human exploration.
Biography in the user profile
Author(s) and Presenter(s)
Author(s):
Dr. Michael H Hecht
4/26/2017 CIM | TPMS |
https://www.cim.org/en/TPMSEvent/Chair/ChairAbstractPool.aspx 2/2
[Unknown Title] MIT Haystack Observatory
N/A The MOXIE Team [Unknown Title]
MIT Haystack Observatory
Presenter(s):
Dr. Michael H Hecht[Unknown Title]MIT Haystack Observatory
GOT
OXYGEN?
Mars Oxygen ISRU Experiment
M i E
Jet Propulsion Laboratory California Institute of Technology
J. Mellstrom , Project Manager
ISRU & the human Mars mission
Drake (2009)
With
out I
SR
U (~
35 m
T)
How does it work?
Meyen (2015)
How does it all go together?
4
SOXE Assy Electronics
Sensor Panel
Compressor
A day in the Life
5
Version 8 (12/2/2015-jaj)
B O O T
I D L E RUN
Pump On – CO2 Flow SOXE On – O2 Production
IDLE
Send RUN CMD Sleep
RO
VER
M
OX
IE MO
DES
CAS Sensors On
20 W 20 W
0.73 MB 0.12-0.98 MB 0.01 MB
1 min 1 min 15 – 120 min 90 min
DU
RATIO
N
RA
W D
ATA R
ATE
Send SW- Selct CMD
SOXE Heaters On
Retrieve Data
<5
min
W
ake
15 min – TBD
0.12 MB
2x 10A Switch
OFF
0.0
4 M
B
Total:
PO
WER
/ENER
GY
230 W
250 W 320 Watts
350 W-hr 80-640 W-hr Energy:
30 min
Data: 1.0-1.9 MB
2x 10A Switch
ON
Time: 120-230 minutes
Power: 320 W max
Energy: 440 - 1000 W-hr
136 Bytes/s
Bold = nominal design case
0 MB
6 W-hr
Ready to Uplink Data
to Rover
Requirement Goal Threshold
Oxygen Production Rate 8 g/hr at 5 Torr, 0ºC. 6 g/hr at 5 Torr, 0ºC. Oxygen Purity 99.6% 98% Number of Cycles 20 10
Formal Requirements
System Performance
• O2 production – >1g/hr per cell (10 cells) • Operational Cycle – >45 cycles w/ no failures • O2 purity – All recent stacks exceed 99.9% • Limited by:
• Inlet flow (pump capacity, gas density at landing site) • Available power (4A limit, equiv. to 12 g/hr) • SOXE capability (10 cells, 22.7 cm2/cell)
Making O2 with SOXE
SOXE Assembly
8
Boudouard and Ni Oxidation Limits
ASR resilience to cycling
Voltage[V]
Currentdensity[A]
Voc
ASR=dV/di(Ω-cm2)
CO2 compression strategy Scroll pump chosen for real time compression to ~1 bar
without intermediate storage.
Energy efficient, can be scaled at least 10-fold. Lifetime TBD.
Performance: 83g/hr for inlet gas P=7 Torr, T= 20°C.
Stationary Scroll
Attaches Directly to
Housing
Housing
Moving Scroll
Cam Followers Limit Moving Scroll
Movement
Eccentric
Dust concern retired During operation (~100 hrs):
Airflow a few cm/s
Expect ~50 mg dust , <0.1 g/m2
Passive exposure (>10,000 hrs)
Expect 10-6 g/m2-s ~2 g/m2
Larger particles
Saltation, pebbles will be stopped by baffles
Significant pressure drops begin at 1 g/m2 for dp=0.15 μm. (Thomas et al. 1999)
Cross section correction expect no problems below ~10 g/m2
Tests confirm no effect for comparable loading with Mars simulant (2-10 μm)
Slip factor provides up to x10 additional margin
Dust exposure at Aarhus wind tunnel
Clean Passive Active
State of the Project
All except electronics & some mechanical through CDR
Extended SOXE life test now at ~50 cycles
Integrated tests exploring safe operating conditions
Outstanding issues
Electronics/software behind schedule
Some unusual (COTS) sensor behavior
On track for flight delivery in November, 2018
Flight-like engineering model to be delivered to MIT for mission support and ongoing testing ~4/19
13
Extensibility Power scaling
Mass & Volume scaling
M2020 MOXIE
Full Scale MOXIE
Where does the power go?
15
Would scale to 51 kW at 2 kg/hr!
But…
Power scaling assumptions Scales with production rate R (2000/12 (g/hr) = x167):
Electrolysis (including enthalpy) – rigorously!
Compression
Scales with # of modules (x6, 334 g/hr each, ~sixty 10x10 cm cells) Sensors
Electronics
Scales with surface area R2/3 (x30) SOXE heat loss
Expected improvements: Compression power assumed to be 70% of scaled value
Lower elevation (like MSL or VL2) gets you to 75%
Reduce output pressure
Increase utilization (more SOXE cells or CO2 recovery)
Custom DC converters improve from 83% to 90% efficient
Gas pre-heat replaced by heat exchange with exhaust
Sensor panel captures heat from, e.g., pump body
Projected power usage
Electrolysis
Compression
Heatloss
Sensors
Electronics
DCConversion
MOXIE-NG,2KG/HR,25.1KW
Consistent with DRA 5.0
Electrolysis
CompressionHeatloss
Sensors
Electronics
DCConversion
MOXIE(12G/HR,308W)
Where does the mass go?
18
Would scale to 2730 kg at 2 kg/hr!
But…
Mass scaling assumptions Scales with production rate R (x167):
SOXE cell mass
Compressor mass
Filter assembly
Scales with # of modules (x6)
Sensors
Electronics
Scales with surface area R2/3 (x30)
Thermal (insulation, etc.)
Structure
Inletassembly
Compression
SOXEcells
SOXEAssembly
ProcessM&C
Electronics
Thermal
Mechanical
MOXIE(12G/HR,16.4KG)
Inletassembly
Compression
SOXEcells
SOXEAssembly
ProcessM&C
Electronics
ThermalMechanical
MOXIE-NG,2KG/HR,1010KG
Projected mass usage
Consistent with M-WIP study
Potential improvement: Small filter assembly following dust-tolerant first stage pump
Other potential improvements
Higher temperature operation
Lower pressure operation
Higher utilization factor (low flow or CO2 re-use)
Advanced controls and improved autonomy
SMART Control
F. Meyen thesis
Special thanks to the amazing JPL Project Team!
MOXIE Testbed
Sponsors and Partners Supported by HEO/AES, STMD/Tech Demos
Mars 2020 Project managed by SMD
is brought to you by…
JetPropulsionLaboratoryCaliforniaInstituteofTechnology
M iE
JetPropulsionLaboratoryCaliforniaInstituteofTechnology
JetPropulsionLaboratoryCaliforniaInstituteofTechnologyJohnson Space Center
ISRU Technology, NASA GRC
Aarhus wind tunnel
Thank you,
Congrats & Thanks, Forrest!
GOT
OXYGEN?
Mars Oxygen ISRU Experiment
M i E
Backup: More MOXIE
25
Abstract
Essential subsystems of the Mars Oxygen ISRU Experiment (MOXIE) on NASA’s Mars 2020 mission have passed their Critical Design Review, and the project is beginning a flight build stage that will culminate in delivery of flight hardware in late 2018. Also being delivered to the MOXIE Science Team is an Engineering Model, equivalent in form, fit, and function to the flight hardware, that will support Mars 2020 mission operations and subsequent extensions of the MOXIE flight demonstration (for example, tests of long duration operation). As a scale model of a future oxygen production facility on Mars, MOXIE will generate a minimum of 6 g/hr high purity oxygen from the Martian atmosphere in at least 15 separate runs, sampling different environmental conditions on Mars, in the 2.5 years following landing of the Mars 2020 rover in February, 2021. The presentation will review the MOXIE scroll pump for CO2 collection and compression, the solid oxide electrolysis system and its packaging for CO2 conversion to O2, the monitoring and control subsystem, and the expectations for operation on Mars.
What does MOXIE do?
27
Rover Chassis
MOXIE Chassis
RAMP
Thermal & Mechanical Interface
Oxygen Plant
Intake Mars
Atmosphere
Exhaust O2, CO+CO2
Electronics Data Acquisition & Control, Power Conversion & Distribution
RPAM Power
Process Control Process Monitor
CO2 Acquisition & Compression
O2 Production Solid Oxide Electrolysis
(SOXE)
Composition Measurement
RCE Data B
RCE Data A
1:200 scale production 1:100 scale operating life
Jet Propulsion Laboratory California Institute of Technology
Mars 2020 Project
SOXE
CO2intaketocathode
O2productfromanode
CO2flo
w
throughmanifoldtocathode
CO/CO2
exhaustfromcathode
CO/CO2flow fieldovercathode
Electrode
Anode
Cathode
Electrolyte
Electrode
SOXE 11 cell stack fabricated by
Ceramatec
4 4.5 5 5.5 6 6.5 7 7.5 8Ambient pressure (Torr)
4
5
6
7
8
9
10
11
12
13
14
Max a
llow
ed O
2 p
rodu
ction
(g
/hr)
Pump capacity assuming 79 g/hr at 7.6 Torr
50% Utilization30% Utilization
29
Pump capacity (at 20°C inlet)
Predicted site highs
(dust storm)
Predicted lows
(summer night)
Predicted site highs
(fall day)
(Arrows are for VL-2 site)
Inlet filter assembly& baffle
30
Inlet Filter Assembly
Baffle
More on the Dust Story
Pressure drop of fluid with a viscosity 1.1x10-5 Pa-s, through a 0.4 mm long, 1 µm radius tube, using slip friction coefficients from 1 to 104 and inlet velocities of 0-5 cm/s
𝚫P vs. P (mbar) at constant v
6 17
0
0.4
Pressure (mbar) 𝚫
P (m
bar)
Measured result at Aarhus using laser Doppler anemometer to measure inlet velocity v.
Yet more on dust…
32
Pressure drop, ΔP, shown to scale with face velocity in Aarhus test