Turbulent Flow Over Craters on Mars: Vorticity Dynamics Reveal Aeolian Excavation Mechanism

DSpace/Manakin Repository

Turbulent Flow Over Craters on Mars: Vorticity Dynamics Reveal Aeolian Excavation Mechanism

Show full item record

Title: Turbulent Flow Over Craters on Mars: Vorticity Dynamics Reveal Aeolian Excavation Mechanism
Author(s):
Anderson, William;
Day, Mackenzie
Date Created: 2017-10-27
Item Type: article
Keywords: Show Keywords
Abstract: Impact craters are scattered across Mars. These craters exhibit geometric self-similarity over a spectrum of diameters, ranging from tens to thousands of kilometers. The late Noachian-early Hesperian boundary marks a dramatic shift in the role of mid-latitude craters, from depocenter sedimentary basins to aeolian source areas. At present day, many craters contain prominent layered sedimentary mounds with maximum elevations comparable to the rim height. The mounds are remnants of Noachian deposition and are surrounded by a radial moat. Large-eddy simulation has been used to model turbulent flows over synthetic craterlike geometries. Geometric attributes of the craters and the aloft flow have been carefully matched to resemble ambient conditions in the atmospheric boundary layer of Mars. Vorticity dynamics analysis within the crater basin reveals the presence of counterrotating helical vortices, verifying the efficacy of deflationary models put forth recently by Bennett and Bell . . . and Day et al. . . . We show how these helical counterrotating vortices spiral around the outer rim, gradually deflating the moat and carving the mound; excavation occurs faster on the upwind side, explaining the radial eccentricity of the mounds relative to the surrounding crater basin.
Publisher: American Physical Society
ISSN: 2470-0045
Link to Related Resource: http://dx.doi.org/10.1103/PhysRevE.96.043110
http://dx.doi.org/10.1103/PhysRevE.96.043110
Persistent Link: http://hdl.handle.net/10735.1/5831
Bibliographic Citation: Anderson, W., and M. Day. 2017. "Turbulent flow over craters on Mars: Vorticity dynamics reveal aeolian excavation mechanism." Physical Review E 96(4), doi:10.1103/PhysRevE.96.043110
Terms of Use: ©2017 American Physical Society. All Rights Reserved.

Files in this item

Files Size Format View
JECS-5767-7754.68.pdf 11.21Mb PDF View/Open Article

This item appears in the following Collection(s)


Show full item record