AlAA 2004-Abstract Applications of Space-Filling-Curves to Cartesian Methods for CFD
نویسندگان
چکیده
The proposed paper p resen ts a v a r i e t y nove l uses o f S p a c e F i l l i n g -Curves (SFCs) f o r Car tes ian mesh methods i n CFD. Whi le thesetechniques w i l l be demonstrated u s i n g n o n b o d y f i t t e d Car tes ianmeshes, most a r e a p p l i c a b l e on genera l b o d y f i t t e d meshes bo ths t r u c t u r e d and uns t ruc tu red . We demonstrate t h e use o f s i n g l e O(N l o gN) SFC-based r e o r d e r i n g t o produce s ing le-pass (O(N)) a l g o r i t h m s f o rmesh p a r t i t i o n i n g , m u l t i g r i d coarsening, and in ter -mesh i n t e r p o l a t i o n .The in termesh i n t e r p o l a t i o n opera to r has many p r a c t i c a l a p p l i c a t i o n si n c l u d i n g “warm s t a r t s ” on m o d i f i e d geometry, o r as an i n t e r g r i dt r a n s f e r ope ra to r on remeshed reg ions i n moving-body s i m u l a t i o n s .E x p l o i t i n g t h e compact c o n s t r u c t i o n o f these opera to rs , we f u r t h e rshow t h a t these a l g o r i t h m s a r e h i g h l y amenable t o p a r a l l e l i z a t i o n .Examples u s i n g t h e SFC-based mesh p a r t i t i o n e r show n e a r l y l i n e a rspeedup t o 512 CPUs even when u s i n g m u l t i g r i d as a smoother. P a r t i t i o ns t a t i s t i c s a r e presented showing t h a t t h e SFC p a r t i t i o n s are, on-average, w i t h i n 10% o f i d e a l even w i t h o n l y around 50,000 c e l l s i neach sub-domain. R e s u l t s a r e a l s o presented on d i s t r i b u t e d computingc l u s t e r s . The in ter -mesh i n t e r p o l a t i o n opera to r a l s o has l i n e a rasymptot ic comp lex i t y and can be used t o map a s o l u t i o n w i t h Nunknowns t o another mesh w i t h M unknowns w i t h O(max(M,N)) ope ra t i ons .T h i s c a p a b i l i t y i s demonstrated b o t h on moving-body s i m u l a t i o n s and i n mapping s o l u t i o n s t o pe r tu rbed meshes f o r f i n i t e d i f f e r e n c e b a s e dg r a d i e n t des ign methods.
منابع مشابه
Applications of Space-Filling Curves to Cartesian Methods for CFD
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تاریخ انتشار 2003