The nonlinear periodic response characteristics of symmetrically and nonsymmetrically
excited oval cylindrical shells are investigated using the first order shear deformation
theory based finite strip method. The periodic solutions of the governing second
order equations of motion are obtained using the shooting technique coupled
with Newmark time marching and the arc length continuation algorithm.
The effect of ovality parameter and loading locations on the steady state
frequency response and modal participation factors is studied. For circular shells
(),
travelling waves emanating at loading point but moving in opposite directions for certain
range of forcing frequency are brought out. For the symmetrically excited oval shell
with
,
due to 1:1 internal resonance between the AS/SS and SA/AA modes, a secondary
branch with traveling wave response emanates from the primary one through a
symmetry breaking bifurcation. For the nonsymmetrically excited oval shells
(),
either waves moving in anticlockwise direction or those originating near the major
axis and moving in opposite directions in the top and bottom halves of the shell are
observed for certain forcing frequency ranges.