| Extensive use of fossil fuels such as oil and coal is an important cause of air pollution,Using clean energy to realize the transition of energy resources from the“high-carbon”to“low-carbon”imminent.Solar energy clean and resource-rich,with good application prospects,Compared with conventional fossil energy,solar energy has high dispersion,low energy density and relatively poor grade,Based on the organic Ranking Cycle（ORC）system,solar energy is collected and then used to generate electricity,which is one of the main technical routes for solar energy utilization.In order to ensure the power generation efficiency of solar ORC systems,it is necessary to select a suitable working medium according to the solar radiation intensity.There are obvious regional differences in solar radiation intensity,and it is necessary to study how to select the appropriate working medium for solar energy ORC systems according to different solar energy utilization zones.The main research contents,conclusions and innovations of this article are as follows.1.Solar ORC System Mathematical Modeling,Established energy flow mathematical modeling for solar energy ORC systems,Discussed the parameters of the thermal oil parameters,cooling water parameters on the system power performance,It was found that when the working medium is different,not only the system power generation efficiency is different,but also the ORC system’s optimal operating conditions are different.2.Based on the principle of highest power generation efficiency of the system,an optimized matching study of the solar ORC system was conducted.The area ratio of evaporator,condenser and solar collector was introduced.,α、β,The two parameters are established as independent variables,and the system efficiency is the function of dependent variable.It can be used to determine the optimum value of the candidate working medium of solar ORC system.The best of the three candidate organic materials for the solar ORC system in Beijing were determined:（1）For R123,the optimal value ofα,βis 5.3/k1,26.2/k2（2）For R245fa,the optimal value forα,βis 7.0/k1,31.2/k2（3）For isopentane,the optimal value forα,βis 4.88/k1,11.5/k2;Based on the principle of the highest ORC power generation efficiency,the most appropriate working fluids were found to have differentαandβvalues.which isk1α∈（4.61,7.66）,k2β∈（10.87,18.7）,the best choice is isopentane.k1α∈（4.97,8.07）,k2β∈（24.73,38.18）,the best choice is R123.k1α∈（8.95,10.98）,k2β∈（38.18,46.67）,the best choice is R245fa.3.Research on Regional and Seasonal Changes of Power Generation Efficiency of Solar ORC System,using the climate parameters in Beijing,the effect of solar radiation intensity and outdoor temperature on the efficiency of solar energy ORC systems using different candidate refrigerants was quantitatively analyzed.4.Selection of Organic Working Medium for ORC System in Different Solar Energy Utilization Area,comparative analysis of the ORC system organic medium selection criteria,according to the building thermal design division and solar resource division standard,divide our country into 11 solar energy utilization areas.Using Solar Energy ORC Thermodynamic Energy Flow Mathematical Model,take the principle of the highest monthly average thermal power generation efficiency for solar energy ORC systems,Map recommended working fluid for solar ORC system.The above research results have been published in academic journals such as《ACTA ENERGIAE SOLARIS SINICA》and《Journalof Termal Sienceand Tchnolohcegy》... |
