Question

Spectral energy is equal to ___________

(a) Kinetic energy per unit mass per unit wavenumber

(b) Rate of dissipation of turbulent energy per unit mass per unit wavenumber

(c) Rate of dissipation of turbulent energy per unit wavenumber

(d) Kinetic energy per unit wavenumber

This question was addressed to me in an international level competition.

Asked question is from Turbulence Modelling in chapter Turbulence Modelling of Computational Fluid Dynamics

Answer 1

The correct answer is:

(a) Kinetic energy per unit mass per unit wavenumber

Spectral energy in turbulence refers to the distribution of kinetic energy across different wavenumbers in the flow. It quantifies the energy contained in a specific range of scales or wavenumbers in the turbulence spectrum.