Evolution of geometric structures in intense turbulence

Abstract

We report measurements of the evolution of lines, planes and volumes in an intensely turbulent laboratory flow using high-speed particle tracking. We find that the classical characteristic timescale of an eddy at the initial scale of the object considered is the natural timescale for the subsequent evolution. The initial separation may only be neglected if this timescale is much smaller than the largest turbulence timescale, implying extremely high turbulence levels.