title: Turbulent dynamics of polymer solutions
abstract: We study properties of dilute polymer solutions. The probability density function (PDF) of polymer end-to-end extensions R in turbulent flows is examined. We show that if the value of the Lyapunov exponent lambda is smaller than the inverse molecular relaxation time 1/tau then the PDF has a strong peak at the equilibrium size R0 and a power tail at R>>R0. This confirms and extends the results of J. L. Lumley [Symp. Math. 9, 315 (1972)]. There is no essential influence of polymers on the flow in this regime. At lambdatau>1 the majority of molecules is stretched to the linear size R(op)>>R0, which can be much smaller than the maximal length of the molecules due to their back reaction.
authors.affiliation: Physics Department, Weizmann Institute of Science, Rehovot 76100, Israel and School of Mathematics, Institute for Advanced Study, Einstein Drive, Princeton, New Jersey 08540, USA.
authors.initials: E
authors.lastname: Balkovsky
authors.initials: A
authors.lastname: Fouxon
authors.initials: V
authors.lastname: Lebedev