Assessing the performance of a scroll expander with a selection of fluids suitable for low-temperature applications

This paper presents calculations of micro organic Rankine cycles equipped with a scroll expander whose performance is simulated by a model reported in literature. In particular, the original working fluid (R245fa) is replaced with selected hydrofluorocarbons and hydrocarbons for assessing the performance of the power cycle as a function of the specific working fluid. After setting the power output from the expander at 2 kW, the relationship between cycle efficiency and maximum cycle temperature is presented for each fluid. Thus, the possibility of matching the operation of the organic Rankine cycle to heat sources at lower temperature is investigated.