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Arina, R. (author), Ceresola, N. (author)
A numerical simulation of the turbulent flow field of a transonic cavity and its associated far-field sound radiation, are presented. The test case is based on the experimental case M219 of QinetiQ. Two different turbulent simulations are performed, the first one is a URANS simulation with a k-w-EARSM turbulence model. while a DES turbulence...
conference paper 2006
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Regnström, B. (author)
The Theodorsen-Garrick conformal mapping is used to make a grid around a wing section and to compute the potential flow around it. The potential flow is a solution to the incompressible Euler equations and can be used to verify the inviscid part of RANS codes.
conference paper 2006
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Diarra, D. (author), Velaga, D. (author), Lucka, K. (author), Köhne, H. (author)
In this paper the fluid dynamics of three cool flame vaporizers are investigated numerically, using a commercial CFD-code. The paper focuses on analyzing local and global residence time distributions (RTD). Two approaches have been used to model the RTD: a transient step tracer model (which serves as a reference) and a dispersed phase tracer model.
conference paper 2006
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Duda, P. (author), Cebula, A. (author), Dwornicka, R. (author)
High thermal stresses are created during the operation of power block devices such as boiler drums, outlet headers, steam valves, turbines and heat exchangers. Due to a cyclic character of such stresses, a phenomenon of low-cyclic fatigue occurs, which may lead to the formation of fractures. Manufacturers of power block devices frequently advice...
conference paper 2006
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Peter, J. (author), Mayeur, J. (author)
This paper describes the recent activities developed at ONERA in the field of aerodynamic shape optimization using gradient based methods. Both discrete direct differentiation method and discrete adjoint method have been considered for the computation of the derivatives of a function with respect to the design parameters. The numerical methods...
conference paper 2006
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Mola, A. (author), Formaggia, L. (author), Miglio, E. (author)
A tool for the prediction of the performances of olympic rowing boats is presented and discussed. The equations of motion for the dynamical system composed by the boat, oars and oarsmen are obtained by means of suitable models for the rowers motion, oar forces and fluid-structure intercation forces. The proposed algorithm is implemented in a C++...
conference paper 2006
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Hemida, H. (author), Krajnovic, S. (author)
Large-eddy simulation (LES) is made to investigate the flow around a generic train under side wind conditions. Two different side-wind yaw angles are used in the investigation: 35 and 90 degrees. The Reynolds numbers based on the height of the train and the freestream velocity are 300,000 and 370,000 for the 90 and 35 degrees yaw angles,...
conference paper 2006
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Manservisi, S. (author)
Optimal boundary control problems associated with the Navier-Stokes equations coupled with the energy equation have a wide and important range of applications. Velocity, pressure and temperature describe most systems and the control through their boundary conditions is the most common in their optimal design. Despite the fact that this field has...
conference paper 2006
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Nishikawa, N. (author), Kaita, K. (author), Ishide, T. (author)
Flow field around a projectile after thrust has been stopped and in inertia flight is studied numerically by a finite difference scheme. This study aims at clarifying the mechanism of free flight, which is generated and developed by rotation of body and gravity. Among two types of projectiles concerned a three-dimensional flow around the slender...
conference paper 2006
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Cuenot, B. (author), Boileau, M. (author), Pascaud, S. (author), Mossa, J.B. (author), Riber, E. (author), Poinsot, T. (author), Bérat, C. (author)
Large Eddy Simulation (LES) is now recognized as an efficient numerical tool to predict gaseous combustion in industrial burners, and a number of examples of applications can be found in the literature. In these examples, the accuracy and the predictive capacity of LES are clearly demonstrated, even for unsteady phenomena. However most...
conference paper 2006
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Boulanger, P. (author), Garcia, M.J. (author), Badke, C. (author), Ryan, J. (author)
using graphical means, in certain cases it is even possible to alter parameters of the computation whilst it is running, depending on what the scientist sees in the current visual output. This ability to monitor and change parameters of the computational process at any time and from anywhere is called computational steering. By combining this...
conference paper 2006
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Stridh, M.L.O. (author), Eriksson, L.E. (author)
The linear harmonic approach has been applied for solving problems involving for example blade vibrations or unsteady blade row interaction effects in multistage axial compressors and turbines. The flow is decomposed into a time averaged flow and an unsteady flow perturbation which are governed by the Reynolds Averaged Navier Stokes (RANS) and...
conference paper 2006
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Van Treeck, C. (author), Wenisch, P. (author), Borrmann, A. (author), Pfaffinger, M. (author), Egger, M. (author), Wenisch, O. (author), Rank, E. (author)
The paper addresses the current state of the development of a computational steering environment (CSE) for interactive indoor thermal comfort simulation by utilizing high-performance supercomputing facilities. The CSE consists of a parallel CFD kernel, a fast spacetree-based 3D mesh generator and an integrated virtual reality-based visualization...
conference paper 2006
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Pourquie, M.J. (author), Boersma, B.J. (author)
This article discusses the use of immersed boundary methods for the flow around objects. Treated are the reasons for their use, their benefits compared to other methods, their importance, and possible further developments.
conference paper 2006
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Borrel, M. (author), Ryan, J. (author), Billet, G. (author)
A patch adaptive mesh refinement (AMR) platform is presented. Presently two Navier-Stokes solvers are available within this platform : a MUSCL and DG solver (FLUX AMR) and a multi-species MUSCL solver (MAJIC) for reacting flows. The first solver is based on cell centered approaches of finite volume type, the second solver is based on a cell...
conference paper 2006
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Stoevesandt, B. (author), Shishkin, A. (author), Peinke, J. (author), Wagner, C. (author)
Since the accuracy of the widely used Reynolds Averaged Navier Stokes (RANS) approach is limited simulating turbulent flow separation on airfoils, we applied a spectral/hp element method to predict the turbulent flow separation at an airfoil for an angle of attack of 12°. The spectral/hp approach allows to solve the incompressible Navier-Stokes...
conference paper 2006
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Panara, D. (author), Porta, M. (author), Schoenfeld, T. (author)
The use of wall functions has been investigated for LES and URANS numerical simulation in pulsating and oscillating channel flow applications. The results show that the wall function approach is accurate in the so-called quasi-steady regime but there are discrepancies with the experimental results in the intermediate frequency range. A special...
conference paper 2006
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Hauke, G. (author), Doweidar, M.H. (author), Fuster, D. (author)
A-posteriori error estimation of convection-dominated and hyperbolic flow problems remains one of the largest challenges in computational mechanics. The available techniques are either non-robust (i.e. the predicted error differs by orders of magnitude from the exact error) or computationally involved (i.e. requiring the solution of additional...
conference paper 2006
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Destuynder, P. (author), Santi, F. (author)
An aeroelastic modelling of an axisymmetrical airship is discussed in this paper. The main difficulty is due to the fact that instabilities are not axisymmetrical. Furthermore an Euler-Lagrange kinematical coupling is necessary in order to represent the fluid-structure interaction. Our strategy is based on some arbitrary change of domain (for...
conference paper 2006
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Larese DeTetto, A. (author), Rossi, R. (author), Idelshon, S. (author), Onate, E. (author)
Several comparisons between experiments and computational models are presented in the following pages. The objective is to verify the ability of Particle Finite Elements Methods (PFEM) to reproduce hydraulic phenomena involving large deformation of the fluid domain.
conference paper 2006
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