The anisotropic diffusion model (ADM) that proposed for noise removal of band-pass signals is developed to a three dimensional model to decompose forced homogeneous turbulence into coherent and incoherent parts. The incoherent part represents the noisy data in the flow field, however the coherent part represents the important data for turbulence studies. The velocity flow field is generated by the Lattice Boltzmann method with resolutions of 128~(3) and 256~(3) grid points, respectively. The high rotational method, namely the Q-identifying method, is used to identify the vortical structures. The scalar tensor Q is the second invariant of the velocity gradient tensor The ADM filtering model is applied against the scalar field Q. Results show that the model is a promising tool for fluid dynamics applications. The method identifies the coherent vortices with similar geometrical shapes to the vortices in the original field. The proposed filtering method also isolates the non-organized structureless regions successfully.
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