By Clemens Verhoosel, and Sai Divi

immersed analysispotential flowtrimminglagrange multiplier

This example demonstrates the immersed (isogeometric) finite element method for the simulation of a two-dimensional non-lifting potential flow over a cylinder. A rectangular ambient domain of size L×L is considered, from which a circle of radius R is trimmed, resulting in the physical domain Ω. Neumann conditions are imposed on all boundaries in accordance with the exact solution. A zero-average potential constraint is added using a Lagrange multiplier to yield the (well-posed) boundary value problem.