Advanced materials for the impeller in an ORC radial microturbine

For distributed generation with low-temperature sources, the micro organic Rankine cycle is an exceptional option. However, an abundance of work remains to minimise its high cost; for example, the expander represents up to 70% of the total capital cost. This paper proposes the design of a lean radial microturbine, which reduces production costs through simplification strategies e.g. alternative materials for the impeller, since low-temperatures allow the possibility of using polymers. The candidate materials are a composite (PEEK-GF30) and a thermoplastic (ABS); aluminium is used as a reference. The study is developed in five stages, namely, heat-mass balance (HM both alternative materials are selected for prototyping using automated machining and additive manufacturing respectively.