A new high temperature fuel cell-micro gas turbine physical emulator has been designed and installed in the framework of the European Integrated Project “FELICITAS” at the Thermochemical Power Group (TPG) laboratory. The test rig is based on a commercial 100 kWe recuperated micro gas turbine (TURBEC T100) modified to be connected to a modular volume designed for physical emulation of fuel cell stack influence. The test rig has been developed starting with a complete theoretical analysis of the micro gas turbine design and off-design performance and with the definition of the more flexible lay-out to be used for different HS (MCFC or SOFC) emulation. The lay-out of the system (connecting pipes, valves, and instrumentation, in particular mass flow meter locations) was carefully designed, and is presented in details in the paper. Particular attention has been focused on the viscous pressure loss minimization to: (i) reduce the unbalance between compressor and expander; (ii) to maintain a high measurement precision; (iii) to have an effective plant flexibility. Moreover, the volume used to emulate the cell stack has been designed to be strongly modular (different from similar system developed by NETL-DOE) to allow different volume size influence on the mGT rig to be easily tested. The modular high temperature volume has been designed using a CFD commercial tool (Fluent). The CFD analysis has been used to reach (i) a high level of uniformity in the flow distribution inside the volume, (ii) to have a velocity field (m/s) similar to the one existing inside the emulated cell stack, and (iii) to minimize (as possible) the pressure losses. The volume insulation will also allow to consider a strong thermal capacity effect during the tests. This paper reports the experimental results of several tests caried out on the rig (using the mGT at electrical stand-alone conditions) at different load values and at both steady-state and transient conditions. The largest number of experimental data available during the tests have been also used for the validation of the theoretical transient model of the rig developed at TPG with the TRANSEO tool. The results are very good and show the already tested capability of TRANSEO to properly evaluate transient performance of complex gas turbine based systems.
