Elastic-wave energy flux

For displacement velocity

\overset{u}{˙}

and stress

σ

, the instantaneous elastic-energy flux is

P_{i} = - σ_{ij} \overset{u}{˙}_{j} .

For complex harmonic amplitudes, its average over one temporal period is

⟨ P_{i} ⟩ = - \frac{1}{2} Re (σ_{ij} \overset{u}{˙}_{j}^{*}) .

 Ancestors (5)