Investigate if forcing IHC=2 leads to any performance issues

[Manangka]

We want to add support for IHC mode 2

Notes:

• According to the Modflow readthedocs:
  ihc is an integer flag indicating the direction between node n and all of its m connections. If IHC = 0 then the connection is vertical. If IHC = 1 then the connection is horizontal. If IHC = 2 then the connection is horizontal for a vertically staggered grid.

• We don't expect many changes for supporting IHC=2 mode. The cl1,cl2 and hwva values should be computed the same way as for IHC1. CDist does differ and needs to be accounted for. In most cases the vertical component
  of the distance of CDist is negligible

• We won't implement IHC=0. We only support horizontal partitioning

Questions:

• Would forcing IHC=2 lead to any performance issues

Notes:

• Ask Martijn about any theoretical consequences
• Do stress test, preferably with converted LHM case (Ask Teun or Huite for this data)

[Manangka]

In GitLab by @luitjansl on Oct 17, 2023, 15:33

added #590 as child task

[Manangka]

added #592 as child task