From 5d364cc560be724cc84e283de1400fd6fd429558 Mon Sep 17 00:00:00 2001
From: Paul Egberts <56635911+plgbrts@users.noreply.github.com>
Date: Thu, 28 Apr 2022 16:35:35 +0200
Subject: [PATCH] Explanation for  primary variable switches

---
 opm/models/blackoil/blackoilprimaryvariables.hh | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/opm/models/blackoil/blackoilprimaryvariables.hh b/opm/models/blackoil/blackoilprimaryvariables.hh
index c4faaba18..89a0ca575 100644
--- a/opm/models/blackoil/blackoilprimaryvariables.hh
+++ b/opm/models/blackoil/blackoilprimaryvariables.hh
@@ -470,7 +470,12 @@ public:
                 }
             }
          }
-
+        //  Primary variable switches possibilities for black-oil (from -> to)
+        //  Sw_po_Sg (3-phase)    -> Rvw_po_Sg, Sw_pg_Rv, Rvw_pg_Rv, Sw_po_Rs
+        //  Sw_pg_Rv (water-gas)  -> Rvw_pg_Rv, Sw_po_Sg, Rvw_po_Sg
+        //  Rvw_po_Sg (gas-oil)   -> Sw_po_Sg, Rvw_pg_Rv 
+        //  Rvw_pg_Rv (gas)       -> Sw_pg_Rv, Rvw_po_Sg
+        //  Sw_po_Rs (water-oil)  -> Sw_po_Sg 
         if (primaryVarsMeaning() == Sw_po_Sg) {
 
             // special case for cells with almost only water