| 1 | Implementation of a Roughness Element to Trip Transition in Large-eddy Simulation显示文摘In aerodynamics, the laminar or turbulent regime of a boundary layer has a strong influence on friction or heat transfer. In practical applications, it is sometimes necessary to trip the transition to turbulent, and a common way is by use of a roughness element(e.g. a step) on the wall. The present paper is concerned with the numerical implementation of such a trip in large-eddy simulations. The study is carried out on a flat-plate boundary layer configuration, with Reynolds number Rex=1.3×106. First, this work brings the opportunity to introduce a practical methodology to assess convergence in large-eddy simulations. Second, concerning the trip implementation, a volume source term is proposed and is shown to yield a smoother and faster transition than a grid step. Moreover, it is easier to implement and more adaptable. Finally, two subgrid-scale models are tested: the WALE model of Nicoud and Ducros(Flow Turbul. Combust., vol. 62, 1999) and the shear-improved Smagorinsky model of Lévêque et al.(J. Fluid Mech., vol. 570, 2007). Both models allow transition, but the former appears to yield a faster transition and a better prediction of friction in the turbulent regime. | J.Boudet J.-F.Monier F.Gao | 2015 | Journal of Thermal Science2015，24，1： | 2 |
| 2 | Numerical studies towards practical large-eddy simulation显示文摘大旋涡的模拟开发和确认为狂暴的内部流动的改进模拟被介绍。数字方法根据二竞争标准被建议:数字质量(精确并且光谱特征) ,并且适应性到复杂配置。首先,方法在学术测试用例上被测试,以便与基本研究缩短。一致结果用能适应的有限体积方法被获得,与更高的顺序移流流动,含蓄的格子过滤和鈥渓o w 花费鈥 ? 砍改进 Smagorinsky 模型。这分析特别地集中于吝啬的流动,变化,二点的关联和系列。而且,指数的平均是为在有确定的摇摆的复杂几何学的 LES 实现的一个有希望的工具,这被显示出。最后,方法的适应性被申请在 turbomachine 表明到片尖端清理流动的一个配置代表。 | J.Boudet J.Caro L.Shao E.Lév(?)que | 2007 | Journal of Thermal Science2007，16，4： | 1 |
您所在的机构暂未开通此部分的功能，请联系管理员