  The interaction of polymers with small-scale velocity gradients can trigger a
coil-stretch transition in the polymers. We analyze this transition within a
direct numerical simulation of shear turbulence with an Oldroyd-B model for the
polymer. In the coiled state the lengths of polymers are distributed
algebraically with an exponent alpha=2 gamma-1/De, where gamma is a
characteristic stretching rate of the flow and De the Deborah number. In the
stretched state we demonstrate that the length distribution of the polymers is
limited by the feedback to the flow.
