Paper Title
FEM for Stress Reduction by Optimal Auxiliary Holes in a Uniaxially Loaded composite Plate

Abstract
When a circular hole is introduced in a rectangular composite plate, the discontinuity arises which leads to increase in stress at the point on the edge of the hole. This will lead to failure of the component at the region of high stress concentration. This has to be avoided by means of providing auxiliary holes. In this view the work is carried out to locate auxiliary holes with a optimum values of auxiliary hole location and with optimum radii using numerical method. In the present work composite plate with a hole for woven glass epoxy material subjected to uniaxial load is analysed and also the effect of fiber orientation on stress concentration is graphically represented. The introduction of auxiliary holes at a optimum location and radii with its effect on stress concentration is also represented graphically. The finite element analysis package ANSYS 9.0 is used to analyse the composite plate. The analysis is carried out using shell 99 element. Further the ANSYS optimization module is used to determine the location and radii for optimum values of auxiliary holes to reduce stress concentration. All the results for different diameter to plate width ratio are presented graphically. It is found from the study that introduction of auxiliary holes on either side by using composite plate reduce stress concentration factor by a factor of 9 to 28 percentage. The work is concluded with various graphs which can be used to locate auxiliary holes for minimum stress concentration. Index Terms- Finite Element Method, Optimization, Stress concentration factor, auxiliary holes.