[Crib-list] CANCELLED...SPEAKER: Yuexia Luna Lin (SEAS, Harvard Univ.) -- Computational Research in Boston and Beyond Seminar (CRIBB) -- Friday, March 6, 2020 from 12:00 PM - 1:00 PM in Building 32, Room 124 (STATA)

[Shirley Entzminger]

 		 SEMINAR CANCELLED...  TO BE RESCHEDULED...


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 		Computational Research in Boston and Beyond Seminar

 				(CRIBB)



DATE:		Friday, March 6, 2020 -- "CANCELLED"

TIME:		12:00 PM to 1:00 PM

LOCATION:	Building 32, Room 124

  		      Enter... 32 Vassar Street
  		               Cambridge, MA


  	            (Pizza & beverages will be provided at 11:45 AM outside
  		             Room 32-124


TITLE:		Reference map technique: a fully Eulerian method for
 		    fluid-structure interactions


SPEAKER:	Yuexia Luna Lin (SEAS, Harvard University)


ABSTRACT:

Fluid-structure interactions (FSI) are abundantly observed in contexts ranging 
from swimming in the pool, to industrial level manufacturing, to bacteria 
collective motion on a petri dish.  However, the governing equations are only 
analytically trackable in the simple cases, making simulations key to 
understand this fantastic class of problems. Conventional computational methods 
often create a dilemma for fluid-structure interaction (FSI) problems. 
Typically, solids are simulated using a Lagrangian approach with a grid that 
moves with the material, whereas fluids are simulated using an Eulerian 
approach with a fixed spatial grid. FSI methods often require some type of 
interfacial coupling between the two different perspectives.  We present a 
fully Eulerian FSI method that addresses these challenges.  The method makes 
use of reference map, which maps the solid in the current space to the 
reference space. Reference map is a common concept in finite strain theory, but 
it has been under-utilized as a primary variable for solid and FSI simulations. 
A challenge in applying the reference map technique (RMT) in FSI is to 
extrapolate reference map values from grid cells occupied by the solids to 
unoccupied grid cells, in order to calculate derivative using finite difference 
schemes.  This challenge becomes more acute when applying RMT to simulations in 
3D.  We develop an extrapolation algorithm based on least-square linear 
regression that is suitable for parallelization.  We show examples to 
demonstrate that RMT is well suited for simulating soft, highly-deformable 
materials and many-body contact problems.  Joint work with Nicholas Derr and 
Chris H. Rycroft (SEAS, Harvard University) and Ken Kamrin (Mechanical 
Engineering, MIT).


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Massachusetts Institute of Technology
Cambridge, MA


For information about the Computational Research in Boston and Beyond Seminar
(CRIBB), please visit....

  			http://math.mit.edu/crib/



===

Shirley A. Entzminger
Administrative Assistant II
Department of Mathematics
Massachusetts Institute of Technology
77 Massachusetts Avenue
Building 2, Room 350A
Cambridge, MA 02139
PHONE:	(617) 253-4994
FAX:	(617) 253-4358
E-mail:	daisymae at math.mit.edu