The motivation for this PR is that currently the build fails on my
Ubuntu 17.10 laptop with two processes because that machine "only" has
8 GB of RAM (granted, the optimization options may have been a bit too
excessive). under the new scheme, each specialization of the simulator
is put into a separate compile unit which is part of
libopmsimulators. this has the advantages that the specialized
simulators and the main binary automatically stay consistent, the
compilation is faster (2m25s vs 4m16s on my machine) because all
compile units can be built in parallel and that compilation takes up
less RAM because there is no need to instantiate all specializations
in a single compile unit.
on the minus side, all specializations must now always be compiled,
the approach means slightly more work for the maintainers and the
flow_* startup code gets even more complicated.
in particular, this implied some changes to the MPI initialization
code. since dune-fem's GridPart class currently has issues with
CpGrid's implementation of loadBalance(), parallel computations still
do not work if dune-fem is around, but at least sequential ones now
do even if MPI is enabled.
No extra equation is added for polymer in the well equation.
Seperate executables are added for polymer: flow_ebos_polymer
and solvent: flow_ebos_solvent
Tested and verified on the test cases in polymer_test_suite
This PR should not effect the performance and results of the blackoil
simulator
it uses ebos for linearization of the mass balance equations and the
current flow code from opm-simulators for all the rest. currently, the
results match the ones from plain `flow` for SPE1, SPE9 and Norne, but
performance is not optimal: on SPE9, converting from and to the legacy
data structures takes about a third of the time to do the actual mass
balance assembly. nevertheless `flow_ebos` is almost as fast as plain
`flow` for SPE9. (for Norne `flow_ebos` is about 15% slower, even
though the results match quite closely. the reason for this is that it
requires more iterations for some reason.)
