Study On The Thermodynamic Properties Of The Ocean Thermal Energy Conversion And Solar Energy Thermal Power Generation Combined System

Ocean thermal energy conversion and solar energy are clean and renewable energy,and their reasonable development and utilization can ease a series of problems such as the energy crisis, environmental pollution as well as the sustainable development and so on. Only by means of the ocean thermal energy conversion power generation system exists many problems such as lower generating efficiency, higher power consumption,larger investment and so on. Only by means of solar energy driven inland solar thermal power plant also exists the problems of lower thermal efficiency, discontinuous and unstable power generation, extra installation of heat storage device and pipeline system,which results in complex structure and high cost of the whole power plant system. Ocean thermal energy conversion originates from the solar and polar ice cold energy. In the area near the equator, ocean thermal energy conversion is abundant because of direct sunlight.Therefore the region with rich ocean thermal energy conversion also has a wealth of solar energy. Design and research on the thermodynamic performance of the ocean thermal energy conversion combined solar energy thermal power generation system can solve the problem of the ocean thermal energy conversion and the solar thermal power generation system, which can also relief the problems of the current energy, environmental and social development.In this paper, taking the ocean thermal energy conversion combined solar energy thermal power generation system as the research object, the working principle of this system is introduced. The mathematical model of ocean thermal energy conversion combined solar energy thermal power generation system is established and analyzed.R134 a, R717 and R22 were identified as candidates by the selection principle. Aspen plus software is used to establish the simulation model of the ocean thermal energy conversion combined solar energy thermal power generation system. Based on the simulation results and the first and second law of thermodynamics, the effects of the R717, R134 a, R22 three kinds of refrigerant and refrigerant expander inlet temperature and pressure on the system thermal efficiency, pump power and exergy loss were analyzed.Through the simulation of the system, it shows that compared with the traditional closed ocean thermal energy generation system, the thermal efficiency of ocean thermal energy conversion combined solar energy thermal power generation system can increased to 7.82% from 4 ~ 5%. Three indexes such as thermal efficiency, pump power consumption and exergy loss of R134 a, R717 and R22 were compared for the oceanthermal energy conversion combined solar energy thermal power generation system. By comparison, it can be found that R134 a has the maximum thermal efficiency, minimum exergy loss and a good environmental performance, so it can be determined as the optimal refrigerant. The R134 a is used as the ocean thermal energy conversion combined solar energy thermal power generation system to analyze the the effect of thermodynamic parameters such as the expander inlet temperature, expander inlet pressure on the thermal efficiency, pump power, energy loss. The research shows that the thermal efficiency increases gradually with the expander inlet temperature, reaches the highest point at160℃ and after that the thermal efficiency decreases. The thermal efficiency increases with the increase of the inlet pressure of the expander. The pump power decreases slightly with the increase of the expander inlet temperature, but increases slightly with the increase of expander inlet pressure. Exergy loss changes little with the increase of expander inlet temperature. Exergy loss decreased slightly with the increase of the expander inlet pressure.