Numerical simulations of turbulent channel flows, with or without additives, are limited in the extent of the Reynolds number ($\text{Re}$) and Deborah number ($\text{De}$). The comparison of such simulations to theories of drag reduction, which are usually derived for asymptotically high $\text{Re}$ and $\text{De}$, calls for some care. In this paper we present a study of drag reduction by rodlike polymers in a turbulent channel flow using direct numerical simulation and illustrate how these numerical results should be related to the recently developed theory.

• Received 10 June 2007

DOI:https://doi.org/10.1103/PhysRevE.77.046309