  During division in animal cells, the actomyosin cortex has been found to
exhibit counter-rotating cortical flows, also known as chiral flows, along the
axis of division. Furthermore, such chiral surface flows were shown to
influence cellular rearrangements and drive the left-right symmetry breaking in
developing organisms. In spite of this prospective biological importance, at
the current state, no numerical simulations have been done to study the
influence of chiral flows on the cell cortex shape. To deepen the insight on
that matter, we present here a numerical study of an axi-symmetric viscoelastic
surface embedded in a viscous fluid. To investigate the influence of a chiral
flow field on the surface shape and material transport, we impose a generic
counter-rotating force field on this surface which induces a chiral flow field.
Notably, we find that the building of a neck, as is observed during cell
division, occurs if there is a strong shear elastic component. Furthermore we
find that a large areal relaxation time results in flows towards the equator of
the surface. These flows assist the transport of a surface concentration during
the forming of a contractile ring. Accordingly, we show that chiral forces by
themselves can drive pattern formation and stabilise contractile rings at the
equator.
