Coupled Poisson

This tutorial composes two independent Poisson Problems with a scalar Lagrange-multiplier Interaction. The complete steady workflow is:

Problem + Problem + Interaction -> LinearAdapter -> solve -> output

The application adds the bulk and embedded Problems to a LinearAdapter, then adds the continuity Interaction using their semantic solution Fields. Each Problem is prepared with setup(). After the solve, OutputHandler writes both solution Fields and the multiplier directly from the adapter state.

Run the generated parameter file with:

build-debug/coupled_poisson_debug \
  build-debug/tutorials/coupled_poisson/coupled_poisson.prm

The output directory and all physical output names are configured in the parameter file.