In CAE analysis of polymer flow, the aspect ratio (AR) of a tetrahedral mesh element is defined by 3Ri/Ro, where, Ri is the radius of a sphere inscribed in the tetrahedral element and Ro is that of a sphere circumscribed. This equation gets normalized and gives values between 0(bad) and 1(good). AR=1 is that of an equilateral tetrahedron. What is the numerical significance of this criterion (AR=1)? What (quality) is the flow phenomenon of a viscoelastic fluid under this condition and AR=0?

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