[Legat]

Hi everyone! Is there Comsol Multyiphysics users?
I'm trying to simulate process into ore-termal furnace and i have some questions for some physics modules:
1. At first ore-termal furnace is powered by a three-phase current network. At normal work regime electrodes connected by the delta schem of connection. At another work regime electrodes connected by the Y-schem of connection. In "Electric Circuit" module make a Y-schem of connection is not a problem, because a ground (neitral) connection is present. But an attempt to create a schema with delta connection results in an error, because in this schem a ground (neitral) connection is absent. How can i realize a delta schem connection?
2. One of the domains is modeled by the porous medium (layer of the bulk materials). To account for the heat consumption for heating the incoming material i use the "Heat Source" element into Heat transfer module. I applied it to the porous media domain with the negative value, but no changes happened. What am I doing wrong?
Thanks for answers!