Data-Analysis of the Coarse-Grained Velocity Gradient Tensor

We present the co-evolved statistics of the Lagrangian velocity gradient tensor and material volume, coarse-grained on a range of scales in high fidelity direct numerical simulation data. Defining the velocity gradient tensor over a representation of fluid volume, we obtain a joint dynamical system whose statistical evolution is closely related to a variety of turbulence characteristics, such as: flow topology, deformation of material volume, energy cascade and intermittency. Therefore this analysis searches for commonalities and differences of the joint system that depend on scale. This poster will provide additional technical details on the data-analysis used to enable our machine learning of the coarse-grained velocity gradient tensor.