BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:CESS Seminar: Three-dimensional X-ray tomography for multiscale ch
 aracterization and fatigue damage investigations of composites for wind tu
 rbine blades
DTSTART:20181221T121500
DTEND:20181221T130000
DTSTAMP:20260508T174151Z
UID:1cfcf6391dd65dad6151bceaa46be28de2355b0226a4425f37dc86ef
CATEGORIES:Conferences - Seminars
DESCRIPTION:Lars P. Mikkelsen obtained his PhD in Solid Mechanics in 1995 
 at the Technical University of Denmark (DTU). After that\, he has been a C
 arlsberg Clare Hall visiting follow at the Cambridge Center for Micromecha
 nics as well as a visiting scholar at Harvard University. Has since 2001 w
 orked at the current geographic location near Roskilde in Denmark\, first 
 as a senior scientist at the Material Research Department at the Risø Nat
 ional Laboratory and latest as an associate professor and head of section 
 for the Composite Mechanics and Structure section at the DTU Wind Energy. 
 Has more than 25 years’ of experience working with numerical modelling a
 nd experimental characterization of materials and structures. In the last 
 10 years\, the work has focused on research in composite materials regardi
 ng compression strength and fatigue behavior of the load carrying laminate
 s in wind turbine blades. During this\, technique such as x-ray computer t
 omography and commercial finite element codes together with user defined u
 ser subroutines is used. Organizes onsite and e-learning courses on the ma
 ster and PhD-level in those fields in addition to supervision of master an
 d PhD students. Have throughout the years published more than 80 papers of
  which more than 40 is in international journals. Has two patent applicati
 ons on strain gauges designs for composite testing.\nKey mechanical proper
 ties of the load carrying composite laminates in wind turbine blades are t
 he stiffness\, fatigue resistance and the compression strength. While the 
 overall design criteria for glass fiber composites mainly are stiffness dr
 iven\, it tends to be more fatigue and compression strength driven when us
 ing carbon fiber or glass/carbon hybrids.\nUsing lab-source x-ray computer
  tomography in connection with ex-situ fatigue testing of quasi unidirecti
 onal composites\, the local fiber failure can be followed. The material in
 vestigated is typical non-crimp fabric used in wind turbine blades. The fa
 tigue damage evolutions is studied during tension/tension\, tension/compre
 ssion and compression/compression fatigue. It is found that the location o
 f the tension/tension (R=0.1) and tension/compression (R=-1) fatigue damag
 e are controlled by the bundle architecture\, while the compression/compre
 ssion (R=10) show up as small shear cracks located in the matrix between t
 he fibers. In addition to fatigue damage investigations\, the fiber archit
 ecture inside the fiber bundle and the fiber bundle architecture is studie
 d. Based on a dictionary based segmentation method\, the fiber-architectur
 e inside the fiber bundle is explored.\nThree-dimensional X-ray computer t
 omography large amount of data\, typical between 2-50GB from each dataset.
  During publication\, only a small amount of such data set can be shown. T
 herefore conclusions from such studies can be doubtful\, if not the full d
 ata-set is made available together with the publication. Strategies for ho
 w to do this will be presented at the end of the talk.  \n 
LOCATION:GC B1 10 https://plan.epfl.ch/?room=GCB110
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR