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AAE450 Spring 2009
Passive Thermal Control Barbeque mode
– .1 deg/sec Space blanket
– Kapton: .005” thick, $15.50 per ft^2– Teflon: .031” thick, $21.47 per ft^2
Heat Pipe– .25” to 1” outside diameter carries 100W to 1000W– >10 kg for 1 m of pipe
Caitlyn McKayStructures and Thermal
AAE450 Spring 2009
Active Thermal Control cryogenic cooler
– turbo-Brayton cryocoolers• very small mass and size• 4 to 10 Kelvin range
– Sunpower M77• $40,000• lift 4W at 77K for 100W input• large mass
Caitlyn McKayStructures and Thermal
AAE450 Spring 2009
Barbeque Mode Used in Apollo Initial attitude that would place the
spacecraft side-on to the Sun while avoiding gimbal lock
Rotation of axis can begin to rotate causing coning
Tracking programs used to carefully control overall attitude as rotation progressed
Caitlyn McKayStructures and Thermal
AAE450 Spring 2009
Space Blanket Hubble has 16 thin layers of dimpled
aluminized Kapton material covered by outer aluminized Teflon shell
less than one tenth of an inch thick Allows rovers to use smaller solar panels
and batteries
Caitlyn McKayStructures and Thermal
AAE450 Spring 2009
Space Blanket Teflon
– withstand 260 ° C
Kapton– withstand -268 ° C to 400 ° C– .005” thick = 27 ft^2/lb
Caitlyn McKayStructures and Thermal
AAE450 Spring 2009
Cryogenic Cooler Reverse-Brayton Cryocooler
– centrifugal compressor, recuperative heat exchanger, expansion turbine and thermal interfaces to the load and heat rejection devices
– radiator used to reject heat from the compressor space
Caitlyn McKayStructures and Thermal
AAE450 Spring 2009
turbo-Brayton Cryocooler Creare, Inc compressor, counterflow heat exchanger
and tuboalternator (expander) 1 million RPM used on NIMCOS
Caitlyn McKayStructures and Thermal
AAE450 Spring 2009
References Barbeque Mode
– How Apollo Flew to the Moon by W. David Woods
Space Blanket– nasa.gov– kapton.dupont.com– professionalplastics.com
Caitlyn McKayStructures and Thermal