Spectral triad interaction
= Spectral triad interaction
{title2=$\mathbf k+\mathbf p+\mathbf q=0$}
The quadratic nonlinear term of the <Navier-Stokes equation> couples three <Fourier modes> whose <wave vectors> close to a triangle. These <spectral triad interactions> transfer <kinetic energy> between wave numbers. A <turbulence closure> can model their triple correlations while retaining more scale information than a prescribed local power law.