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On Heatshield Shapes for Mars Entry CapsulesThe 70deg sphere-cone - the standard geometry for all US Mars entry missions - is thoroughly examined via flow field simulations at a select few peak heating points along candidate flight trajectories. Emphasis is placed on turbulent heating based on the Baldwin- Lomax turbulence model. It is shown that increased leeward turbulent heating for a 70 sphere-cone flying at angle of attack is primarily due to the discontinuity in curvature between the spherical nose cap and the conical frustum - the attachment of the sonic line at this sphere-cone junction leads to a supersonic edge Mach number over the leeward acreage. In an attempt to mitigate this problem of elevated turbulent heating, alternate geometries, without any curvature discontinuities in the acreage, are developed. Two approaches, one based on nonlinear optimization with constraints, and one based on the use of non-uniform rational B-splines, are considered. All configurations examined remain axisymmetric. The aerothermal performance of alternate geometries is shown to be superior to that of the 70 sphere-cone.
Document ID
Acquisition Source
Ames Research Center
Document Type
Conference Paper
Prabhu, DInesh K.
(Engineering Research and Consulting, Inc. Moffett Field, CA, United States)
Saunders, David A.
(Engineering Research and Consulting, Inc. Moffett Field, CA, United States)
Date Acquired
August 25, 2013
Publication Date
January 9, 2012
Subject Category
Spacecraft Design, Testing And Performance
Report/Patent Number
Meeting Information
Meeting: 50th AIAA Aerospace Sciences Meeting
Location: Nashville, TN
Country: United States
Start Date: January 9, 2012
End Date: January 12, 2012
Sponsors: American Inst. of Aeronautics and Astronautics
Funding Number(s)
Distribution Limits
Public Use Permitted.
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