Thermodynamic Analysis of Nanofluid-based ORC System using Cavity Receiver: Effect of Solar Irradiation

Application of the nanofluid as a heat transfer fluid of the solar system is suggested as an effective way for thermal performance enhancement. Also, Organic Rankine Cycles (ORCs) are researched as an interesting technology for converting the thermal energy to the power (electricity or work). In the current study, a dish collector using a cubical cavity receiver was used as a heat source of the ORC system. The Al2O3/thermal oil nanofluid was used as the solar heat transfer fluid. Methanol was used as the ORC working fluid.Thermodynamic analysis was carried out at the superheated condition, constant evaporator pressure of 2.5 MPa, and condenser temperature of 300 K. The effects of the solar irradiance was studied the thermodynamic performance of the investigated solar ORC system. The solar irradiation was varied in the range of 400-1200 (W/m2). The results indicated that the ORC mass flow rate, ORC net work, and ORC total irreversibility enhanced with increasing solar irradiation. Also, the results revealed that the ORC net work, and ORC total irreversibility of the investigated solar ORC system increased by increasing the turbine inlet temperature.

Keywords:

Thermodynamic analysis , cubical cavity receiver , , solar ORC , nanofluid