Characterization of chaotic dynamics-I: dynamical invariants of sheared polymer solutions

Stress measurements as a function of time in aqueous polymer solutions show the presence of sustained dynamic features for identifiable steady shear regions. The analysis of post-transient time-series data, reveals the presence of low-dimensional chaotic dynamics. Interestingly, the results obtained from different types of polymer solutions, viz., thermosensitive polymers and biopolymers, show similar complex dynamical features and suggest that mechanisms responsible are common. The experimental data have been analyzed with a view to characterizing the strange attractor in terms of invariant measures such as the correlation, embedding, Lyapunov dimensions and entropy