Numerical investigation of flow field and structure of a micro-axial turbine of ORC using R245fa

Environmental damage has been gradually increasing over the past few decades owing to industrialization. In many countries, attempts have been made to reduce carbon emissions by employing energy-saving and sustainability methods, such as waste heat recovery and renewable energy, respectively. For low-grade waste heat recovery, the organic Rankine cycle is a typical thermo-electric conversion system. In the present study, a thermodynamic analysis showed that the output power, working fluid mass flow rate, inlet temperature, and inlet and outlet pressures of a turbo-expander were 12.57 kW, 1.6 kg/s, 70 ℃, 0.53 MPa, and 0.267 MPa, respectively. Moreover, the one- and three-dimensional geometries of the turbo-expander were analyzed by using aerodynamic and computational fluid dynamics software, respectively. Additionally, the effect of the tip clearance between the blade tip and casing on the performance, stress, and strain of the blade was investigated, and the tip clearance was varied from 0% to 10%, at an interval of 5%. The results showed that as the tip clearance increased, the shaft power, isentropic efficiency, stress, and strain decreased. In addition, the effect of the tip clearance on the isentropic efficiency and structure was higher in the range of 0-5% than that in the range of 5-10%. Finally, when the tip clearance was 5%, the shaft power and isentropic efficiency were 14.87 kW and 61.12%, respectively     «

Environmental damage has been gradually increasing over the past few decades owing to industrialization. In many countries, attempts have been made to reduce carbon emissions by employing energy-saving and sustainability methods, such as waste heat recovery and renewable energy, respectively. For low-grade waste heat recovery, the organic Rankine cycle is a typical thermo-electric conversion system. In the present study, a thermodynamic analysis showed that the output power, working fluid mass f...     »