Assessment of Dissipation in LES Based on Explicit Filtering from the Computation of Kinetic Energy Budget

Energy dissipation in Large-Eddy Simulations (LES) based on the explicit filtering of the flow variables is investigated. An equation for the turbulent kinetic energy budget including the dissipation resulting from the filtering is first derived from the filtered compressible Navier-Stokes equations. A round jet at Reynolds number 1.1×104 is then calculated by LES using explicit filtering. Reference solutions are obtained, and compared to experimental data. The contributions of filtering and viscosity to energy dissipation in the jet are discussed. The filtering activity is found to adjust to the grid and flow properties.