The ultra-micro gas turbine generator project at UDR1: Experimental assessment of the compressor map and of the pressure losses at the regenerative combustion chamber

The paper reports the procedures and the results of a series of tests conducted at the Department of Mechanical & Aeronautical Engineering of UDR1 to obtain the map of an ultra-micro radial compressor (Dext = 0.038 m), as well as the head losses and the combustion efficiency of the corresponding ultra-micro combustion chamber. This work is a part of a research aimed at the conception, design and prototyping of an ultra-micro thermo-electrical device for portable power generation. The novelty of the research consists in the fact that the thermal engine is a (ultramicro) gas turbine set. In previous papers the entire course of the project has been described, from the initial feasibility analysis to the optimization of the thermodynamic cycle and the selection of the most convenient materials. In a subsequent stage, several different configurations have been assessed to select the most proper geometry and structural characteristics of the most relevant components (radial compressor, radial turbine, combustion chamber, electrical motor and generator, bearings, regenerative heat exchanger). The final configuration of the prototype (for which a patent is pending) is described in the paper as well, together with some of the results of the final operational tests.