Performance analysis of a combined system for cold and power

• A combined Organic Rankine Cycle and the ejector refrigeration cycle is proposed.
• A turbine is added between the boiler and the ejector.
• The cycle performances are evaluated theoretically using energy methods.
• Several working fluids such as R123, R141b, R245fa, R601a and R600a are considered.
• A one-dimensional mathematical model of the ejector was developed (constant-area).

This paper presents a theoretical study of a combined thermal system, which combines the Rankine cycle and the ejector refrigeration cycle. This combined cycle produces power and refrigeration simultaneously. The thermal system could use low temperature heat sources. A simulation was carried out to evaluate the cycle performance using several working fluids as R123, R141b, R245fa, R601a and R600a. A one-dimensional mathematical model of the ejector was developed using the equations governing the flow and thermodynamics based on the constant area ejector flow model. The ejector is studied in optimal operating regime. The influence of thermodynamic parameters on system performance is studied. The results show that the condenser temperature, the evaporation temperature, the extraction ratio, the fluid nature and the generating temperature have significant effects on the system performances (the coefficient of performance of the combined cycle and the entrainment ratio of the ejector).