A new technique for extracting information about cyclic and periodic features in turbulent-flow f... more A new technique for extracting information about cyclic and periodic features in turbulent-flow fields is proposed. A phase-space decomposition of the flow field is first performed, based on proper orthogonal decomposition (POD), and then recurrence plots (RPs) are used to analyse the system. The technique allows the temporal behaviour of the flow viewed as a dynamic system to be identified. The basic elements of the analysis are presented first, with the Lorenz system used for illustration, and then two related flows field are analysed with the new technique, with results contrasted against the classical spectral analysis.
International Journal for Numerical Methods in Fluids
... 1989. 4, The use of subgrid transport equations in a three-dimensional model of atmospheric t... more ... 1989. 4, The use of subgrid transport equations in a three-dimensional model of atmospheric turbulence - Deardorff - 1973. 3, A new dynamic one-equation subgrid-scale model for large-eddy simulations - Kim, Menon - 1995. ...
Large eddy simulation of turbulent channel flow with dense and small 3D roughness elements is car... more Large eddy simulation of turbulent channel flow with dense and small 3D roughness elements is carried out using a roughness element model. Profiles of mean Reynolds stress, mean velocity and rms velocity as well as turbulent structures near the wall are obtained. The shear stress in the rough wall is larger than that in the smooth wall side and the
The focus of the paper is on the performance of approximate RANStype near-wall treatments applied... more The focus of the paper is on the performance of approximate RANStype near-wall treatments applied within LES strategies to the simulation of flow separation from curved surfaces at high Reynolds numbers. Two types of combination are considered: a hybrid RANS-LES scheme in which the LES field is interfaced, dynamically, with a full RANS solution in the near-wall layer; and a zonal scheme in which the state of the near-wall layer is described by parabolized Navier-Stokes equations which only return the wall shear stress to the LES domain as a wall boundary condition. In both cases, the location of the interface can be chosen freely. The two methods are applied to a flow separating from the trailing edge of a hydrofoil. A second flow considered is one separating from a three-dimensional hill, for which the performance of the zonal method is contrasted with a fine-grid LES and simulations in which the near-wall layer is treated with log-law-based wall functions.
A new technique for extracting information about cyclic and periodic features in turbulent-flow f... more A new technique for extracting information about cyclic and periodic features in turbulent-flow fields is proposed. A phase-space decomposition of the flow field is first performed, based on proper orthogonal decomposition (POD), and then recurrence plots (RPs) are used to analyse the system. The technique allows the temporal behaviour of the flow viewed as a dynamic system to be identified. The basic elements of the analysis are presented first, with the Lorenz system used for illustration, and then two related flows field are analysed with the new technique, with results contrasted against the classical spectral analysis.
International Journal for Numerical Methods in Fluids
... 1989. 4, The use of subgrid transport equations in a three-dimensional model of atmospheric t... more ... 1989. 4, The use of subgrid transport equations in a three-dimensional model of atmospheric turbulence - Deardorff - 1973. 3, A new dynamic one-equation subgrid-scale model for large-eddy simulations - Kim, Menon - 1995. ...
Large eddy simulation of turbulent channel flow with dense and small 3D roughness elements is car... more Large eddy simulation of turbulent channel flow with dense and small 3D roughness elements is carried out using a roughness element model. Profiles of mean Reynolds stress, mean velocity and rms velocity as well as turbulent structures near the wall are obtained. The shear stress in the rough wall is larger than that in the smooth wall side and the
The focus of the paper is on the performance of approximate RANStype near-wall treatments applied... more The focus of the paper is on the performance of approximate RANStype near-wall treatments applied within LES strategies to the simulation of flow separation from curved surfaces at high Reynolds numbers. Two types of combination are considered: a hybrid RANS-LES scheme in which the LES field is interfaced, dynamically, with a full RANS solution in the near-wall layer; and a zonal scheme in which the state of the near-wall layer is described by parabolized Navier-Stokes equations which only return the wall shear stress to the LES domain as a wall boundary condition. In both cases, the location of the interface can be chosen freely. The two methods are applied to a flow separating from the trailing edge of a hydrofoil. A second flow considered is one separating from a three-dimensional hill, for which the performance of the zonal method is contrasted with a fine-grid LES and simulations in which the near-wall layer is treated with log-law-based wall functions.
Uploads
Papers by fabrizio tessicini