BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:Efficient FFT-based Homogenisation without Linear Reference Medium
DTSTART:20180531T161500
DTEND:20180531T171500
DTSTAMP:20260407T055535Z
UID:12e68b45881460bc5e2c73a954cbad93d06402b5222e8b653040d529
CATEGORIES:Conferences - Seminars
DESCRIPTION:Dr. Till Junge -- ​EPFL STI IGM Laboratory for Multiscale
  Mechanics Modeling (LAMMM)​\nAbstract  In the field of computational 
 homogenisation of periodic representative volume elements (RVE)\, over the
  last two decades\, fast Fourier transform (FFT)-based spectral solvers ha
 ve emerged as a promising alternative to the finite element method (FE).\n
 Most spectral methods are based on work of Moulinec and Suquet [1] and spl
 it an RVE's response into that of a linear reference medium and a periodic
  fluctuation due to heterogeneities. The main advantage of this formulatio
 n over FE is that it can be both significantly faster and memory-saving. T
 he two main problems are 1) the choice of the reference medium\, which is 
 typically based on heuristics\, non-trivial and has a strong impact on the
  method's convergence (A bad choice can render the method non-convergent)\
 , and 2) convergence is not uniform. Numerous studies have suggested mitig
 ations to both of these problems (e.g. [2])\, but they have remained subst
 antial disadvantages compared to the more expensive\, but also more robust
  FE.\nRecent work by Zeman et al. [3] proposes a new formulation for spect
 ral solvers which dispenses with the linear reference problem and converge
 s unconditionally. We present µSpectre\, an open implementation of this n
 ovel method and use it to show that the new approach is more computational
 ly efficient than its linear reference medium-based predecessors\, converg
 es in the presence of arbitrary phase contrast - including porosity - and 
 eliminates or drastically reduces Gibbs ringing.\n \n[1] H. Moulinec and 
 P. Suquet. Comput. Methods Appl. Mech. Eng. (1998)\n[2] M. Kabel\, et al
 . Comput. Mech. (2014)\n[3] J. Zeman\, et al. Int. J. Num. Meth. Eng. 
 (2016)\n\nBio Till Junge is an Ambizione Fellow in EPFL's laboratory for 
 multiscale mechanics modeling (LAMMM) and the PI for project µSpectre (ht
 tps://c4science.ch/u/muspectre)\, an open-source platform for efficient FF
 T-based continuum mesoscale modelling. Till graduated from EPFL with a PhD
  in computational mechanics in the civil engineering department in 2014 an
 d subsequently worked at the University of Lausanne and the Karlsruher Ins
 titut für Technologie before coming back to EPFL for his Ambizione Fellow
 ship.\nHe researches novel computational methods in the fields of concurre
 ntly coupled atomistic-continuum multiscale mechanics\, FFT-based contact 
 mechanics\, machine-learning for interatomic potentials and efficient spec
 tral methods for continuum mesoscale modelling.\n 
LOCATION:MED 0 1418 https://plan.epfl.ch/?room==MED%200%201418
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR