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Thermal Model Correlation for Mars Reconnaissance OrbiterThe Mars Reconnaissance Orbiter (MRO) launched on August 12, 2005 and began aerobraking at Mars in March 2006. In order to save propellant, MRO used aerobraking to modify the initial orbit at Mars. The spacecraft passed through the atmosphere briefly on each orbit; during each pass the spacecraft was slowed by atmospheric drag, thus lowering the orbit apoapsis. The largest area on the spacecraft, most affected by aeroheating, was the solar arrays. A thermal analysis of the solar arrays was conducted at NASA Langley Research Center to simulate their performance throughout the entire roughly 6-month period of aerobraking. A companion paper describes the development of this thermal model. This model has been correlated against many sets of flight data. Several maneuvers were performed during the cruise to Mars, such as thruster calibrations, which involve large abrupt changes in the spacecraft orientation relative to the sun. The data obtained from these maneuvers allowed the model to be well-correlated with regard to thermal mass, conductive connections, and solar response well before arrival at the planet. Correlation against flight data for both in-cruise maneuvers and drag passes was performed. Adjustments made to the model included orientation during the drag pass, solar flux, Martian surface temperature, through-array resistance, aeroheating gradient due to angle of attack, and aeroheating accommodation coefficient. Methods of correlation included comparing the model to flight temperatures, slopes, temperature deltas between sensors, and solar and planet direction vectors. Correlation and model accuracy over 400 aeroheating drag passes were determined, with overall model accuracy better than 5 C.
Document ID
Acquisition Source
Langley Research Center
Document Type
Conference Paper
Amundsen, Ruth M.
(NASA Langley Research Center Hampton, VA, United States)
Dec, John A.
(NASA Langley Research Center Hampton, VA, United States)
Gasbarre, Joseph F.
(NASA Langley Research Center Hampton, VA, United States)
Date Acquired
August 23, 2013
Publication Date
July 9, 2007
Subject Category
Lunar And Planetary Science And Exploration
Report/Patent Number
Meeting Information
Meeting: 37th International Conference on Environmental Systems (ICES)
Location: Chicago, IL
Country: United States
Start Date: July 9, 2007
End Date: July 12, 2007
Funding Number(s)
WBS: WBS 441261,94,93,91,94
Distribution Limits
Work of the US Gov. Public Use Permitted.
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