Incubator Designs for Space Flight Application
Optimization and Automation
A. Hoehn, J. B.Freeman, M.Jacobson, L.S.Stodieck
BioServe Space Technologies, University of Colorado
SAE paper 1999-01-2177
29th International Conference on Environmental Systems
July 11-15, 1999, Denver, CO
1
Space Shuttle Experiment Accommodation
2
Experiment Accommodation
environmental control / experiment execution
FP A
GE -FP A
A uto-G A P
IC V
M -F PA
G B A _IC M
BPC S
GEFA
Isolate Gravity as sole independent variable:
uniform ground vs.. flight environment / centrifuge ?
temperature most influential, but: launch / landing, moisture, atmosphere
3
Typical Thermoelectric Heat Pump Assembly
Temperature-Controlled Device
•water-, air-heat exchanger, device
Thermoelectric Heat Pump
Air Heat Exchanger
Forced Convection Cooling
4
Required Heat Pump Capacity
Required Heat Pump Capacity
For 4 Different Ambient Temperature Levels
50
20°C T amb
12 mm foam insulation
25°C T amb
Heat Pump Capacity [W]
40
30°C T amb
35°C T amb
30
20
10
0
-10
-20
0
5
10
15
20
25
30
35
40
Incubator Temperature [°C]
5
Heat Pump Optimization
TEC
TEC
TEC
TEC
TEC
TEC
TEC
TEC
TEC Electric Configuration Effects
for 5 different TEC Modules
100.00
80.00
Type A
60.00
Type B
Type C
40.00
c
Type D
20.00
Type E
4S
x2
P
6S
5S
2S
x2
P
4S
3S
0.00
2S
Electric Pow er [W] per 40
Watt Heat Pum p Capacity
V+
Configuration (serial, parallel)
6
Forced Convective Cooling ?
•Densely packed
•Larger temperature gradients
due to heat transport
Option:
•Water-cooled walls
•External Insulation
•High thermal Conductivity
7
PGBA Thermal Management Subsystem

Solid state Peltier devices used to “pump” heat from liquid loops to air heat
exchanger
8
Temperature Gradients - Heat Transport
Heat Transport in Water
Difference between entrance and exit coolant temperature
6
100 ml/min
Delta Temperature (Entrance - Exit)
[°C]
200 ml/min
5
300 ml/min
400 ml/min
4
30°C ambient temperature
12 mm foam insulation
3
2
1
0
0
10
20
30
40
Incubator Temperature [°C]
9
Temperature Transients
•Loading
•Power Loss
•Transport
•New Setpoint
10
Internal Heat Sources - Gradients
STS-93 STARS Payload:
(Space Technology and Research Students)




Middle and High Schools across US
and Chile participate.
STARS-1 based on experiment
proposed by students in Chile
SPACEHAB Inc., a number of
schools and other organizations
participating
Hardware Highlights:
» 5 habitat for plants, aphids, ladybugs,
butterflies
» 10 high resolution color cameras /
frame grabber
» active temperature control
» passive humidity and gas control
11
Light as heat source
Illuminated Cultures:

Radiant heat transfer:
» 1-3degC temperature increase
» provide conductive pathways
» water-cool directly
12
Individually Controlled Experiment Accommodation
temperature profiles for automated experiment activation and termination
13
Liquid Coolant Loop
9 individual PID controllers under power limit (130 Watt)
14
Individual Temperature Profile Control
lag due to thermal mass
3/3/99 ICM and HOBO data
40
35
Aavg
Bavg
Cavg
Davg
Eavg
Favg
Gavg
Havg
Ahobo
Bhobo
Chobo
Dhobo
Ehobo
Fhobo
Ghobo
Hhobo
30
Temp (°C)
25
20
15
10
5
0
-180
0
180
360
540
MET (min)
720
900
1080
15
Incubator Future

Better insulation: vacuum panels, aerogels
» power reduction
» longer unpowered times (ISS: 2 hrs.)

Unpowered temperature control:
» phase change materials
» vacuum insulation

Transport to / from ISS:
STS-93 7/20/99
» longer temperature stability, even unpowered
16
Acknowledgements
SAE paper 1999-01-2177
Incubator Designs for Space Flight Application
Optimization and Automation
Brian Biesterfeld, Jim Clawson, Jake B.Freeman, Jon
Genova, Don Geering, Kevin Gifford, Mindy
Jacobson, Brett Landin, Diane Naylor, Mark Rupert,
Steve Schneider, Dave Simmons, Louis S.Stodieck
BioServe Space Technologies, University of Colorado
NASA grants: NASA-MAR: NCC8-131 (NASA MSFC
cooperative agreement) and NASA-NCC2-5290
(NASA Ames cooperative agreement).
Debra Reiss-Bubenheim, Rudi Aquilina, Shawn
Bengston, Steve Patterson, NASA Ames Research
Center
17