Feature‐based adaptive mesh refinement for wingtip vortices

Abstract

SUMMARYFeature-based solution-adaptive mesh refinement is an attractive strategy when it is known a priori that the resolution of certain key features is critical to achieving the objectives of a simulation. In this paper, we apply vortex characterization techniques, which are typically employed to visualize vortices, to identify regions of the computational domain for mesh refinement. We investigate different refinement strategies that are facilitated by these vortex characterization techniques to simulate the flow past a wing in a wind tunnel. Our results, which we compare with experimental data, indicate that it is necessary to refine the region within and near the vortex extent surface to obtain an accurate prediction. Application of the identified mesh refinement strategy also produced observed improvement in the results predicted for a spinning missile with deflected canards.

A study of properties of adaptive quadratic grids for three‐dimensional near‐surface field computations

“…57 The field-related terms of the TE expressions are typically used as indicators for solution-based grid adaptation. 58,59,60 Truncation error analysis for high-order meshes has not appeared adequately in the literature. The present study derives the analytic expressions of TE for directional quadratic meshes and performs an assessment of their sensitivity to mesh distortions.…”

“…Comparisons of commonly used a priori mesh quality metrics have also been reported . The field‐related terms of the TE expressions are typically used as indicators for solution‐based grid adaptation , , …”

Dynamic flow‐based particle splitting in smoothed particle hydrodynamics

“…It has the advantage of allowing for local refinement both within the vortical structures shed from the obstacle as well as in regions of high local velocity gradients, such as the attached and separated shear layers. Such feature‐based adaptive refinement has been used before in mesh‐based methods in the case of vortex‐dominated flows , following a variety of feature detection methodologies. The choice here for the magnitude of vorticity further presents the advantage of simplicity, despite the previously noted consequences associated with the fact that this quantity is not a primitive variable.…”

Application of the VORTFIND algorithm for the identification of vortical flow features around complex three‐dimensional geometries

“…One of the contributing factors to this is the poor resolution of vortical structures generated by the hull and control surfaces. Simulations [5,6] show that improved agreement with experimental results may be obtained by locally refining the vortex core region.…”