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Turbulent flow

Turbulent flow

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  • 1 New tools for numerical simulations

    First aerodynamic-aero-acoustic chaining created with an exchange surface crossed by a turbulent flow ("LES" CFD- "Euler" CAA)... This first aerodynamic-aero-acoustic chaining, created with an exchange surface crossed by a turbulent flow, opens the way to future complete aero-acoustic computations for configurations that are today impossible using non- coupled CFD(* Computational Fluid Dynamics) and CAA:* see below
  • 2 Simulation of the noise of landing gear through CFD*

    This noise is a result of multiple interactions between the turbulent flows and the various elements that make up the cell... Appearance of the turbulent flow on a background of non- structured mesh[ Cedre Calculation... Technique for the solving of turbulent flow equations in which the large scales of movement are solved explicitly while the small scales (smaller that the calculation meshes) are modeled by" a vortical viscosity" term
  • 3 Combining Scale Models for the Best... in the Best Way

    Detail of a model of turbulent flow in the vicinity of an aircraft bay... "We are assuming that the angle of stall depends on the transition between a laminar (regular) flow and a turbulent flow (one that generates vortices) ",adds Ivan Mary... Downstream from the transition, the turbulent flow is calculated using statistical methods
  • 4 More realistic virtual engines

    This is also true of turbulent flows where the large-scale vortex structures move constantly and in an unpredictable fashion". Hence the need to develop" unsteady" physical models and numerical methods that can be used to calculate the results of these models
  • 5 Flow field survey and visualization

    For investigations of flow fields with pronounced spatial structures and/or rapid temporal or spatial changes (transition from laminar to turbulent flow, coherent structures, pitching airfoils in transonic flows with shocks, rotors, test facilities with short run time, etc.) new experimental techniques, such as PIV are required which allow to capture the flow velocity of large flow fields instantaneously
  • 6 The Aerodynamicist's Eye

    It allows separations, vortices and turbulent areas to be revealed, in order to understand the structure of the flow and also to prepare further measurements with a hot wire anemometer, or a laser velocimeter for example. Laser tomoscopy is a visualization method for high-speed flows, up to supersonic speeds
  • 7 ONERA-M6 Wing, Star of CFD

    An acenaphthene film spread over the wing has the property of being" ripped off" (we say that it is sublimated) when the flow is turbulent, which helps to differentiate the laminar areas (white) from the turbulent areas (black), with the boundary characterizing the transition... It is an essential parameter for characterizing the flow rate in the boundary layer close to the wall: fully laminar at very low Re, fully turbulent for very large Re, etc.)