Hybrid system emulator enhancement: anodic circuit design

In the framework of the LARGE-SOFC European Integrated Project, an SOFC anodic circuit emulator has been designed to study the interaction between anodic and cathodic sides of the fuel cell stack. This new experimental facility has been designed to be coupled with the cathodic side emulator developed by TPG at the University of Genoa, Italy. This activity has been carried out in order to built a complete hybrid system emulator equipped with a 100 kW recuperated micro gas turbine, a cathodic vessel located between recuperator outlet and combustor inlet, and an anodic circuit based on the coupling of a single stage ejector with an anodic volume. In order to design the anodic circuit test rig, a system analysis has been carried out considering the coupling between a planar SOFC stack and the 100 kW commercial microturbine installed at TPG laboratory. A new hybrid system has been studied and the anodic side properties have been defined in terms of fuel mass flow rate, recirculated mass flow rate, pressures, and temperatures. Starting from these calculations the ejector geometry has been designed and the anodic side volume has been defined. A CFD analysis has been carried out to design the pipes necessary for the connection between the ejector and the anodic volume, and for the anodic side outlet. Particular attention has been devoted to the heat exchanger designed to emulate the anodic flow heating inside the stack. In fact, two original tubolar heat exchangers have been designed to be introduced inside the cathodic volume, in order to exploit the cathodic heat for the anodic side too.