Fibre waviness defects in composite structures

Completed

Renewable Energy Sources(Wind Energy)
Not Energy Related

Basic and strategic applied research

PHYSICAL SCIENCES AND MATHEMATICS (Metallurgy and Materials)
ENGINEERING AND TECHNOLOGY (Mechanical, Aeronautical and Manufacturing Engineering)

Not Cross-cutting

Dr M Sutcliffe
Engineering
University of Cambridge

Standard

EPSRC

01 May 2009

31 July 2012

39 months

£259,704

Materials sciences

East of England

NC : Engineering

Dr M Sutcliffe, Engineering, University of Cambridge

Professor N Fleck, Engineering, University of Cambridge

Project Contact, Dowty Propellers Ltd
Project Contact, Vestas Technology UK Ltd
Project Contact, Simulayt Ltd

Linked to grant EP/G015848/1

Composites are now widely used in a wide range of applications. In the wind turbine and aerospace sectors recent innovations, including larger and more sophisticated structures, have driven the need for better understanding of failure of composite structures. Use of lower-cost process routes requires a need for better understanding of the inevitable defects in such composite structures.Failure ofwell-controlled flat composite panels is now generally well understood. However real manufacturedcomponents contain a range of stress concentrators, some associated with relatively controlled features such as joints, ply drops, sandwich panel closures and holes, some more uncertain associated with defects including fibre waviness, resin-rich areas and gaps at sandwich core breaks. The aim of theproject is to understand and model how such defects affect the strength of the structure.The project has three main strands: (i) characterising realistic defects in industrial components and in controlled laboratory specimens, (ii) identifying mechanisms of compressive failure under fatigue loading and developing predictive models for failure at waviness defects, validated with experiments, (iii)modelling of defect formation during processing. Case studies suggested by industrial partners Dowty and Vestas of a propeller and a wind turbine blade will be used. The models will be incorporated into software tools, in collaboration with Simulayt Ltd, for use in design

27/10/08