For supporting transfer of fields such as density fields which cannot be negative we need at least one method that will not introduce negative values into an all positive field.
Initial implementation of this is to use the Lumped Mass matrix rather than the consistent mass matrix. [1] contains proofs demonstrating that a) lumped mass matrix still maintains the global integral and b) bounds the max and min to the field max and min.
[1] P.E. Farrell, M.D. Piggott, C.C. Pain, G.J. Gorman, and C.R. Wilson. 2009. Conservative interpolation between unstructured meshes via supermesh construction. Computer Methods in Applied Mechanics and Engineering 198, 33–36 (July 2009), 2632–2642. https://doi.org/10.1016/j.cma.2009.03.004
For supporting transfer of fields such as density fields which cannot be negative we need at least one method that will not introduce negative values into an all positive field.
Initial implementation of this is to use the Lumped Mass matrix rather than the consistent mass matrix. [1] contains proofs demonstrating that a) lumped mass matrix still maintains the global integral and b) bounds the max and min to the field max and min.
[1] P.E. Farrell, M.D. Piggott, C.C. Pain, G.J. Gorman, and C.R. Wilson. 2009. Conservative interpolation between unstructured meshes via supermesh construction. Computer Methods in Applied Mechanics and Engineering 198, 33–36 (July 2009), 2632–2642. https://doi.org/10.1016/j.cma.2009.03.004