Von Mises Equivalent Stress

Entity name: Mises

\begin{displaymath}\sigma_{vM} = \frac{1}{\sqrt{2}} \sqrt{(\sigma_{x}-\sigma_{y})^{2}+(\sigma_{y}-\sigma_{z})^{2}+(\sigma_{z}-\sigma_{x})^{2}+6\tau_{yz}^{2}+6\tau_{zx}^{2}+6\tau_{xy}^{2}}\end{displaymath}