  Injection of dilute polymer in a turbulent flow suppresses frictional drag.
This challenging and technologically important problem remains primarily
unresolved due to the complex nature of the flow. An important factor in the
drag reduction is the energy transfer from the velocity field to the polymers.
In this paper we quantify this process using energy fluxes, as well as show its
universality in diverse flows such as magnetohydrodynamics, quasi-static
magnetohydrodynamics, and bubbly turbulence. We show that in such flows, the
transfer from kinetic energy to elastic energy leads to a reduction in kinetic
energy flux compared to the corresponding hydrodynamic turbulence. This leads
to a reduction in nonlinearity of the velocity field that results into a more
ordered flow and a suppression of turbulent drag.
