Optimal Large Eddy Simulation in One Dimension
نویسنده
چکیده
the inner comer, measurements in water confirmed the formation of a counter-rotating vortex in that region. The formation of an infinite sequence of vortices near comers was first predicted by Moffat. 13 Finally, tests with the model inserted backwards in the glycerol flow confirmed that the low-Re cavity flow was essentially reversible. Because insect wings span a wide range of orientations with respect to the relative wind velocity, it was considered worthwhile to run a few tests with the model inserted at different angles relative to the flow direction. As shown in Figs. 6 and 7, an increase in the angle of attack in the range-20 0 to 20 0 resulted in a measurable increase in the size of the separation region. The present results clearly document the characteristics of flow in and above two-dimensional, asymmetric, triangular cavities. Unfortunately, one of the long-term objectives of this work, namely an explanation for the possible aerodynamic effect of such cavities, has not yet been adequately resolved. Nachtigall'sI postulate that scales may increase lift by creating turbulence near the wing is incompatible with the Reynolds number range of such flows. The only possible connection that we have been able to infer is that the asymmetry of the cavities might create a component of the skin friction in the direction normal to the free stream, thus contributing to the lift. Obviously, more work is required in order for this question to be answered. FIG. 6. Separation streamlines for different angles of attack (Re = 0.62).
منابع مشابه
Investigations of Three- Dimensional Turbulent Cavity Flow Using Large Eddy Simulation Approach
متن کامل
Large-eddy simulation of turbulent flow over an array of wall-mounted cubes submerged in an emulated atmospheric boundary-layer
Turbulent flow over an array of wall-mounted cubic obstacles has been numerically investigated using large-eddy simulation. The simulations have been performed using high-performance computations with local cluster systems. The array of cubes are fully submerged in a simulated deep rough-wall atmospheric boundary-layer with high turbulence intensity characteristics of environmental turbulent fl...
متن کاملMixed Large-Eddy Simulation Model for Turbulent Flows across Tube Bundles Using Parallel Coupled Multiblock NS Solver
In this study, turbulent flow around a tube bundle in non-orthogonal grid is simulated using the Large Eddy Simulation (LES) technique and parallelization of fully coupled Navier – Stokes (NS) equations. To model the small eddies, the Smagorinsky and a mixed model was used. This model represents the effect of dissipation and the grid-scale and subgrid-scale interactions. The fully coupled NS eq...
متن کاملBlood Flow Simulation in an Aorta with a mild coarctation Using Magnetic Resonance Angiography and Finite Volume Method
Coarctation of the aorta is one of the five main congenital cardiovascular failures, accounting for 6–8 percent of these failures. This research aimed to simulate the blood flow of a seventeen-year-old male teen with a mild coarctation at one-third of his aorta's descending branch. The simulation was performed by extracting the domain and the input pulsatile velocity signal as the boundary cond...
متن کاملMixed Large-Eddy Simulation Model for Turbulent Flows across Tube Bundles Using Parallel Coupled Multiblock NS Solver
In this study, turbulent flow around a tube bundle in non-orthogonal grid is simulated using the Large Eddy Simulation (LES) technique and parallelization of fully coupled Navier – Stokes (NS) equations. To model the small eddies, the Smagorinsky and a mixed model was used. This model represents the effect of dissipation and the grid-scale and subgrid-scale interactions. The fully coupled NS eq...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2013