The augmented fast marching method for level set reinitialization
David Salac
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Abstract
Including derivative information in the modelling of moving interfaces has been proposed as one method to increase the accuracy of numerical schemes with minimal additional cost. Here a new level set reinitialization technique using the fast marching method is presented. This augmented fast marching method will calculate the signed distance function and up to the secondorder derivatives of the signed distance function for arbitrary interfaces. In addition to enforcing the condition ∇φ 2 = 1, where φ is the level set function, the method ensures that ∇ ( ∇φ ) 2 = 0 and ∇∇ ( ∇φ ) 2 = 0 are also satisfied. Results indicate that for both two-and three-dimensional interfaces the resulting level set and curvature field are smooth even for coarse grids. Convergence results show that using first-order upwind derivatives and the augmented fast marching method result in a second-order accurate level set and gradient field and a first-order accurate curvature field.
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