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The FSA algorithm (4)
The case of submerged structural edges:
• If the structural element has no topological
thickness, the node at the tip is a singular point
as concerns the normal
• FSA strategy outlined so far would
lead to two mutually opposite normals:
one is redundant and should be rejected
• Aligned flow is
undisturbed,
transversal flow
“sticks” at tip
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Shortcomings of the FSA algorithm
• Onset of spurious
velocities in 3-D
models with warped
element faces.
Example: patch test
• Reason: slight but non-negligible accuracy mismatch in calculation
of internal pressure forces and of reactions (direction of the normal)
• FSA method is purely geometrical and uses no information about
internal fluid element formulation (e.g., spatial integration rules)
• Investigate alternative methods based on equilibrium
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