# Taylor's hypothesis

From AMS Glossary

(Redirected from Frozen-turbulence approximation)

## Taylor's hypothesis

An assumption that advection contributed by turbulent circulations themselves is small and that therefore the advection of a field of turbulence past a fixed point can be taken to be entirely due to the mean flow; also known as the Taylor "frozen turbulence" hypothesis.

It only holds if the relative turbulence intensity is small; that is, , where

*U*is the mean velocity and*u*the eddy velocity. Then the substitution*t*=*x*/*U*is a good approximation.