An adaptive local deconvolution method for implicit LES
An adaptive local deconvolution method for implicit LES
复制标题
DOI：
10.1016/j.jcp.2005.08.017
复制
发表时间：
2005-12
期刊：
影响因子：
--
通讯作者：
S. Hickel;N. Adams;J. Domaradzki
中科院分区：
文献类型：
--
作者：
S. Hickel;N. Adams;J. Domaradzki
自适应局部去卷积方法(ALDM)是一种新的用于湍流隐式大涡模拟(ILES)的非线性离散格式。在ILES中，对流项离散化的截断误差作为一个次网格尺度模式。因此，模型隐含地包含在离散化中，并且不需要对模型项进行显式计算。离散化是基于解自适应的反卷积算子，允许控制截断误差。通过对频谱数值粘性的分析，确定了反褶积参数。采用一种基于进化算法的自动优化方法来获得一组参数，使数值粘性与各向同性湍流的理论预测达到最佳的光谱匹配。对大尺度强迫和衰减三维均匀各向同性湍流的数值模拟结果与理论和实验数据吻合较好，表明了隐式模型的良好性能。作为过渡流的一个例子，我们考虑了三维Taylor-Green涡的不稳定性和破裂。隐式模型正确地预测了不稳定的增长和向发达湍流的转变。结果表明，隐式模型的性能至少与已建立的显式模型相当。
The adaptive local deconvolution method (ALDM) is proposed as a new nonlinear discretization scheme designed for implicit large-eddy simulation (ILES) of turbulent flows. In ILES the truncation error of the discretization of the convective terms functions as a subgrid-scale model. Therefore, the model is implicitly contained within the discretization, and an explicit computation of model terms becomes unnecessary. The discretization is based on a solution-adaptive deconvolution operator which allows to control the truncation error. Deconvolution parameters are determined by an analysis of the spectral numerical viscosity. An automatic optimization based on an evolutionary algorithm is employed to obtain a set of parameters which results in an optimum spectral match for the numerical viscosity with theoretical predictions for isotropic turbulence. Simulations of large-scale forced and decaying three-dimensional homogeneous isotropic turbulence show an excellent agreement with theory and experimental data and demonstrate the good performance of the implicit model. As an example for transitional flows, instability and breakdown of the three-dimensional Taylor–Green vortex are considered. The implicit model correctly predicts instability growth and transition to developed turbulence. It is shown that the implicit model performs at least as well as established explicit models.