GenericTransport should accept solver instance, not the class
https://github.com/PMEAL/OpenPNM/blob/007c521a4cb93d45beb26cb878b9b1ee1762a4f8/openpnm/algorithms/_generic_transport.py#L222-L224

Line 224 should be removed, and `getattr(solvers, ws.settings.default_solver)` needs a `()` at the end.
diff --git a/openpnm/algorithms/_generic_transport.py b/openpnm/algorithms/_generic_transport.py
index 45fe89a1d..dda484128 100644
--- a/openpnm/algorithms/_generic_transport.py
+++ b/openpnm/algorithms/_generic_transport.py
@@ -219,9 +219,8 @@ class GenericTransport(GenericAlgorithm, BCsMixin):
 
         """
         logger.info('Running GenericTransport')
-        solver = getattr(solvers, ws.settings.default_solver) \\
-            if solver is None else solver
-        solver = solver()  # Instantiate the fetched solver class
+        if solver is None:
+            solver = getattr(solvers, ws.settings.default_solver)()
         # Perform pre-solve validations
         self._validate_settings()
         self._validate_data_health()
['openpnm/algorithms/_generic_transport.py']