论文标题
通过数据驱动模型的涡流湍流的涡流重建
Vortex-to-velocity reconstruction for wall-bounded turbulence via a data-driven model
论文作者
论文摘要
对涡流结构进行建模,然后将它们转换为相应的速度场是基于涡旋的湍流中基于涡旋的建模作品的两个基本方面。这项工作开发了一种数据源方法,该方法允许基于给定的涡流字段对速度字段进行有效的重建。涡流场通过结合旋转强度和速度梯度张量的真实特征向量而定义为矢量场。研究了涡流场的独特特性,并通过差异几何形状揭示了涡流幅度和方向之间的关系。涡流到速度重建方法结合了涡旋 - 涡流和涡流 - 速度相关信息,并在线性随机估计的框架下得出了诱导模型函数。快速傅立叶变换用于提高实施的计算效率。访问重建精度并将其与广泛使用的生物武器定律进行了比较。结果表明,该方法可以有效地恢复大规模范围内的湍流运动,这对于湍流建模非常有前途。该方法还用于研究不同高度下涡旋的诱导作用,并讨论了一些揭示的结果并与壁结合的湍流中的热研究主题相关。
Modelling the vortex structures and then translating them into the corresponding velocity fields are two essential aspects for the vortex-based modelling works in wall-bounded turbulence. This work develops a datadriven method, which allows an effective reconstruction for the velocity field based on a given vortex field. The vortex field is defined as a vector field by combining the swirl strength and the real eigenvector of the velocity gradient tensor. The distinctive properties for the vortex field are investigated, with the relationship between the vortex magnitude and orientation revealed by the differential geometry. The vortex-to-velocity reconstruction method incorporates the vortex-vortex and vortex-velocity correlation information and derives the inducing model functions under the framework of the linear stochastic estimation. Fast Fourier transformation is employed to improve the computation efficiency in implementation. The reconstruction accuracy is accessed and compared with the widely-used Biot-Savart law. Results show that the method can effectively recover the turbulent motions in a large scale range, which is very promising for the turbulence modelling. The method is also employed to investigate the inducing effects of vortices at different heights, and some revealing results are discussed and linked to the hot research topics in wall-bounded turbulence.