Observation of chaotic dynamics in dilute sheared aqueous solutions of CTAT

The nonlinear flow behavior of a viscoelastic gel formed due to entangled, cylindrical micelles in aqueous solutions of the surfactant cetyl trimethyl ammonium tosilate (C-TAT) has been studied. On subjecting the system to a s tep shear I ate lying above a cer tain value, the shear and normal stresses show interesting time dependent behavior. The analysis of the measured tim e series shows the existence of a finite correlation dimension and a positi ve Lyapunov exponent, unambiguously implying that the dynamics can be descr ibed by that of a dynamical system with a strange attractor whose dimension increases with the increase in sheer rare.