Research On Designing Organic Fluids Turbine Based On Solar Thermal System

Recently, solar thermal power generation technology is one of the most developmentand popular technologies in the new energy field. Organic Rankine cycle circulation solarthermal power generation technology can combine the Organic Rankine circle with thesolar heat collection effectively, it aims mainly at the use of middle and low temperaturesolar energy, and mainly adopts a distributed system. Organic Rankine power generationtechnology has been widely applied in the use of low temperature heat, which hasoutstanding contribution for the energy conservation, environmental protection and wasteheat utilization. The core block of the Organic Rankine circle is the organic workingmedium steam turbines, which is also the core equipment of the conversion of heat intopower, and is the foundation of the system safe operation. However, highly efficient andstable steam turbines applied in the solar heating system are still rare, and the design ofthe organic working medium steam turbines in the higher temperature range is also hardlyseen. This article mainly focused on the design research of the organic working mediumsteam turbines with the heat source temperature of300°C, the research was carried out asfollows:The organic Rankine solar system characteristics at low and middle temperatureranges were studied and then the radial-inward-flow turbine was chosen. With the heatsource condition of300°C, we chose several applicable organic working medium to theaerodynamic design and the thermodynamic calculation. After comparing the structuresize and economic efficiency, we chose the cheap methylbenzene as the working mediumand then studied the aerodynamic design in detail. The pressure ratio reached up to8, andbelonged to the transonic flow. The structure design was conducted using the threedimensional modeling software, variety of nozzle plan and pulley structure and thecircular guide volute were also designed. Based on the CFD calculation, the designedguide cascade was researched, different schemes was optimized, the design requirementsthat the expansion of oblique cut part reached transonic flow was realized, the researchon the expansion of oblique cut part and flow in the annular gap was performed, and theflow of the volute was also explored. The CFD calculation results were feet back to theone dimensional design and three dimensional modeling, the impeller structure and portnumber were optimized, the pneumatic scheme was improved. Then, the full-sizethree-dimensional numerical simulation was performed for the best scheme, the flow wasanalyzed in detail, and the final optimization scheme was designed. The performance anddesign error was very small, and the efficiency reached up to85%. Finally, the CFDcalculations of this model in variable flow operating mode were performed, the performance and flow in variable flow operating mode were also studied.