Performance Prediction and Working Fluid Active Design of Organic Rankine Cycle Based on Molecular Structure

Working fluid selection is crucial for organic Rankine cycles (ORC). In this study, the relationship between molecular structure and ORC performance was established based on quantitative structure–property (QSPR) working parameterized model (WFPM), from which an actively designed. First, QSPR with four properties, namely, critical temperature (Tc), boiling point (Tb), pressure (pc), isobaric heat capacity (cp0), built. Second, evaporation enthalpy (hvap), entropy (svap), thermal efficiency (η) were estimated by WFPM, results compared those using REFPROP to verify calculation accuracy of “QSPR+WFPM” coupling model. The average absolute relative deviations are below 8.44%. maximum error 6%. Then, thermodynamic limit corresponding thermophysical properties ideal calculated at typical geothermal source conditions. Finally, active design conducted Tc pc as target. research shows that C3H4F2 C4H3F5 optimal fluids 473.15 523.15 K sources, respectively.