Advances in Hybrid RANS-LES Modelling

Turbulence modelling has long been, and will remain, one of the most important t- ics in turbulence research, challenging scientists and engineers in the academic world and in the industrial society. Over the past decade, Detached Eddy Simulation (DES) and other hybrid RANS-LES methods have received increasing attention from the turbulence-research community, as well as from industrial CFD engineers. Indeed, as an engineering modelling approach, hybrid RANS-LES methods have acquired a remarkable profile in modelling turbulent flows of industrial interest in relation to, for example, transportation, energy production and the environment. The advantage exploited with hybrid RANS-LES modelling approaches, being - tentially more computationally efficient than LES and more accurate than (unsteady) RANS, has motivated numerous research and development activities. These activities, together with industrial applications, have been further facilitated over the recent years by the rapid development of modern computing resources. As a European initiative, the EU project DESider (Detached Eddy Simulation for Industrial Aerodynamics, 2004-2007), has been one of the earliest and most systematic international R&D effort with its focus on development, improvement and applications of a variety of existing and new hybrid RANS-LES modelling approaches, as well as on related numerical issues. In association with the DESider project, two subsequent international symposia on hybrid RANS-LES methods have been arranged in Stockholm (Sweden, 2005) and in Corfu (Greece, 2007), respectively. The present book is a result of the Second Symposium on Hybrid RANS-LES Methods, held in Corfu, Greece, 17-18 June 2007.

Covers important topics on Hybrid RANS-LES Methods

Klappentext

This volume contains papers contributed to the Second Symposium on Hybrid RANS-LES Methods, held in Corfu, Greece, 17-18 June 2007. All the papers have undergone further review and revision after the symposium, which has covered a number of relevant topics in the field. These include Unsteady RANS and LES, Improved DES Methods, Hybrid RANS-LES Methods, Embedded LES, DES-related Numerical Issues, Performance of the New SAS Model, as well as Industrial Applications of DES. Papers represent a leading part of current studies and achievements on the fundamentals of hybrid RANS-LES methods in general, as well as on their applications to industrial flow problems. Among the contributed papers, three invited keynote papers by B. Geurts, U. Piomelli and P. Sagaut, are presented together with an overview paper by P. Spalart.

Inhalt
The 2007 Hybrid RANS-LES Symposium: An Outsider's View.- The 2007 Hybrid RANS-LES Symposium: An Outsider's View.- Invited Keynote Papers.- Reliability of LES in Complex Applications.- Turbulent Eddies in the RANS/LES Transition Region.- Uncertainty Modeling, Error Charts and Improvement of Subgrid Models.- Hybrid RANS-LES Modelling and Related Numerical Issues.- Hybrid LES-RANS Method Based on an Explicit Algebraic Reynolds Stress Model.- Hybrid LES-RANS: Inlet Boundary Conditions for Flows with Recirculation.- On the Use of Stimulated Detached Eddy Simulation (SDES) for Spatially Developing Boundary Layers.- Synthetic Inflow Boundary Conditions for Wall Bounded Flows.- X-LES Simulations Using a High-Order Finite-Volume Scheme.- One-Equation RG Hybrid RANS/LES Modelling.- Scrutinizing Velocity and Pressure Coupling Conditions for LES with Downstream RANS Calculations.- Comparison of Different Modelling Approaches.- Computation of the Helicopter Fuselage Wake with the SST, SAS, DES and XLES Models.- Numerical Simulation of the Flow in the Wake of Ahmed Body Using Detached Eddy Simulation and URANS Modeling.- DES and Hybrid RANS-LES Modelling of Unsteady Pressure Oscillations and Flow Features in a Rectangular Cavity.- Comparative Assessment of Hybrid LES/RANS Models in Turbulent Flows Separating from Smooth Surfaces.- Numerical Investigation of a Laboratory Combustor Applying Hybrid RANS-LES Methods.- Applications of DES and DES Variants.- DES of a Cavity with Spoiler.- DES Analysis of Confined Turbulent Swirling Flows in the Sub-critical Regime.- Zonal-Detached Eddy Simulation of Transonic Buffet on a Civil Aircraft Type Configuration.- Detached Eddy Simulation of Separated Flow on a High-Lift Device and Noise Propagation.- Unsteady CFD Analysis of a Delta WingFighter Configuration by Delayed Detached Eddy Simulation.- Comparison of DES and LES on the Transitional Flow of Turbine Blades.- Demonstration of Improved DES Methods for Generic and Industrial Applications.- Towards a Successful Implementation of DES Strategies in Industrial RANS Solvers.- Delayed Detached-Eddy Simulation of Supersonic Inlet Buzz.- DES Applied to an Isolated Synthetic Jet Flow.- Advanced URANS Modelling and Applications.- Development and Application of SST-SAS Turbulence Model in the DESIDER Project.- Numerical Simulation of the Dynamic Stall of a NACA 0012 Airfoil Using DES and Advanced OES/URANS Modelling.- Turbulence Modelling of Strongly Detached Unsteady Flows: The Circular Cylinder.- SGS Modelling and LES Applications.- A New Variant of Subgrid Dissipation for LES Method and Simulation of Laminar-Turbulent Transition in Subsonic Gas Flows.- Formulation of Subgrid Stochastic Acceleration Model (SSAM) for LES of a High Reynolds Number Flow.- Flow Around a Surface-Mounted Finite Cylinder: A Challenging Case for LES.- Compressibility Effects on Turbulent Separated Flow in a Streamwise-Periodic Hill Channel - Part 2.