Rarefaction Effects on the Outflow Boundary Conditions for External Subsonic Flows

Date

2008-07-25

Author

Çelenligil, Mehmet Cevdet

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In continuum-flow simulations, subsonic outflow boundary conditions are controlled solely by the Mach number. Such boundary conditions are not suitable for rarefied flows, and it is necessary to include the Knudsen number into them. In the present study, this is done for external flows, by introducing a simple model which adjusts the macroscopic boundary properties (from which the incoming molecules are calculated) according to the local rarefaction. A bridging formula is used between the continuum and free-molecule limits, and the results show considerable improvement in the rarefied-flow simulations.

Subject Keywords

DSMC, Bridging formula, External rarefied flows, Subsonic outflow boundary conditions

URI

https://hdl.handle.net/11511/54066

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Department of Aerospace Engineering, Conference / Seminar

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Citation Formats

M. C. Çelenligil, “Rarefaction Effects on the Outflow Boundary Conditions for External Subsonic Flows,” 2008, vol. 1084, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/54066.