A massively parallel accurate conservative level set algorithm for simulating turbulent atomization on adaptive unstructured grids

This article presents a massively parallel and robust strategy to perform the simulation of turbulent incompressible two-phase flows on unstructured grids in complex geometries. relies combination narrow-band accurate conservative level set (ACLS)/ghost-fluid framework with isotropic adaptive mesh refinement. enables accurately capture interface dynamics topology, small physical scales at liquid-gas are resolved an affordable cost. The ACLS method, even if not strictly mass-conserving, ensures exact conservation smoothed phase indicator, which minimizes liquid mass errors. In framework, presented first Desjardins et al. (2008) [25], is defined as iso-contour hyperbolic tangent function, advected by fluid, then reshaped using reinitialization equation. Several forms this exist: original form proposed involves numerical estimation gradient, difficult compute meshes. It thus susceptible induce artificial deformation interface. A new has been recently Chiodi (2017) [29], takes advantage mapping onto classical distance while much better preserving shape. Nevertheless, implementation requires special care. work, meshes implemented YALES2 low-Mach flow solver. order normals curvature, signed-distance function reconstructed nodes narrow band around Geometric-Projection Marker Method (GPMM). method triangulation geometric projection closest surface elements. Spatial convergence, robustness efficiency overall procedure firstly demonstrated through transport test cases examples. Eventually, emphasize significant computational gain refinement ability large density ratios, two Large-Eddy Simulations (LES) atomizing jets air presented, each one various resolutions. low-pressure water jet quiescent from compound nozzle full computation internal injector flow, latter high-pressure kerosene crossflow. Both simulations validated against experiments, demonstrating potential access deep insight into instabilities 3D