Efficiency and stability of the DSBGK method

Handle URI:
http://hdl.handle.net/10754/552544
Title:
Efficiency and stability of the DSBGK method
Authors:
Li, Jun
Abstract:
Recently, the DSBGK method (Note: the original name DS-BGK is changed to DSBGK for simplicity) was proposed to reduce the stochastic noise in simulating rarefied gas flows at low velocity. Its total computational time is almost independent of the magnitude of deviation from equilibrium state. It was verified by the DSMC method in different benchmark problems over a wide range of Kn number. Some simulation results of the closed lid-driven cavity flow, thermal transpiration flow and the open channel flow by the DSBGK method are given here to show its efficiency and numerical stability. In closed problems, the density distribution is subject to unphysical fluctuation due to the absence of density constraint at the boundary. Thus, many simulated molecules are employed by DSBGK simulations to improve the stability and reduce the magnitude of fluctuation. This increases the memory usage remarkably but has small influence to the efficiency of DSBGK simulations. In open problems, the DSBGK simulation remains stable when using about 10 simulated molecules per cell because the fixed number densities at open boundaries eliminate the unphysical fluctuation. Small modification to the CLL reflection model is introduced to further improve the efficiency slightly.
KAUST Department:
Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division
Citation:
Efficiency and stability of the DSBGK method. AIP Conference Proceedings 1501 , 849 (2012); doi: 10.1063/1.4769631
Publisher:
AIP Publishing
Conference/Event name:
28th International Symposium on Rarefied Gas Dynamics 2012, RGD 2012
Issue Date:
9-Jul-2012
DOI:
10.1063/1.4769631
ARXIV:
arXiv:1207.1040
Type:
Conference Paper
Additional Links:
http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.4769631; http://arxiv.org/abs/1207.1040
Appears in Collections:
Conference Papers; Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorLi, Junen
dc.date.accessioned2015-05-10T14:19:35Zen
dc.date.available2015-05-10T14:19:35Zen
dc.date.issued2012-07-09en
dc.identifier.citationEfficiency and stability of the DSBGK method. AIP Conference Proceedings 1501 , 849 (2012); doi: 10.1063/1.4769631en
dc.identifier.doi10.1063/1.4769631en
dc.identifier.urihttp://hdl.handle.net/10754/552544en
dc.description.abstractRecently, the DSBGK method (Note: the original name DS-BGK is changed to DSBGK for simplicity) was proposed to reduce the stochastic noise in simulating rarefied gas flows at low velocity. Its total computational time is almost independent of the magnitude of deviation from equilibrium state. It was verified by the DSMC method in different benchmark problems over a wide range of Kn number. Some simulation results of the closed lid-driven cavity flow, thermal transpiration flow and the open channel flow by the DSBGK method are given here to show its efficiency and numerical stability. In closed problems, the density distribution is subject to unphysical fluctuation due to the absence of density constraint at the boundary. Thus, many simulated molecules are employed by DSBGK simulations to improve the stability and reduce the magnitude of fluctuation. This increases the memory usage remarkably but has small influence to the efficiency of DSBGK simulations. In open problems, the DSBGK simulation remains stable when using about 10 simulated molecules per cell because the fixed number densities at open boundaries eliminate the unphysical fluctuation. Small modification to the CLL reflection model is introduced to further improve the efficiency slightly.en
dc.publisherAIP Publishingen
dc.relation.urlhttp://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.4769631en
dc.relation.urlhttp://arxiv.org/abs/1207.1040en
dc.rightsArchived with thanks to AIP Conference Proceedingsen
dc.titleEfficiency and stability of the DSBGK methoden
dc.typeConference Paperen
dc.contributor.departmentComputer, Electrical and Mathematical Sciences and Engineering (CEMSE) Divisionen
dc.conference.date2012-07-09 to 2012-07-13en
dc.conference.name28th International Symposium on Rarefied Gas Dynamics 2012, RGD 2012en
dc.conference.locationZaragoza, ESPen
dc.eprint.versionPublisher's Version/PDFen
dc.identifier.arxividarXiv:1207.1040en
kaust.authorLi, Junen
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