摘要
针对太阳能有机朗肯-闪蒸循环(SBFC),本文基于EES(engineering equation solver)软件建立数学模型,以R245fa为循环工质,在集热器出口热水温度介于353.15~373.15K范围内,对平板集热器(FPC)和真空管集热器(ETC)驱动的SBFC系统热力性能以及投资成本进行了对比分析。选用的性能指标参数包括净输出功、热效率、第二定律效率、不可逆损失以及比初始投资。结果表明,随着集热器出口热水温度的增大,SBFC系统的热力性能显著升高,且采用ETC的系统比FPC系统在热力性能上更具优势,该优势随着热水温度的升高而持续增大。研究同时表明,在SBFC的投资成本中,太阳能集热器投资占比最大,且采用ETC的系统比初始投资远大于采用FPC的系统;此外,集热器出口热水温度的升高有利于降低SBFC系统的比初始投资。
A mathematical model for solar binary-flashing cycle(SBFC) driven by flat-plate collectors and evacuated tube collectors was developed based on EES(engineering equation solver) software in this paper. With R245 fa as working fluids, the effect of hot water temperatures at solar collector outlet, ranging from 353.15 K to 373.15 K, on the thermodynamic performance and investment cost of the SBFC system has been analyzed. In the analysis, the net power output, thermal efficiency, exergy efficiency, exergy loss and specific investment cost were selected as performance indicators. Results showed that under the given working conditions, an increase in the hot water temperature at solar collector outlet could significantly improve the thermodynamic performance of the SBFC system. The thermodynamic performance of the system with ETC outperformed that of with FPC; and the advantage increased with the increased hot water temperature at solar collector outlet. Meanwhile, it was also found that the investment cost of solar collector accounted for the largest proportion of the total investment cost and the system with ETC had higher investment cost than that of with FPC. Besides, the specific investment cost decreased with the increased hot water temperature at solar collector outlet.
引文
[1]李晶,裴刚,季杰.太阳能有机朗肯循环低温热发电关键因素分析[J].化工学报,2009,60(4):826-832.LI Jing,PEI Gang,JI Jie.Analysis of key factors in low-temperature solar thermal electric power generation with organic Rankine cycle[J].CIESC Journal,2009,60(4):826-832.
[2]LI J,PEI G,JI J.Optimization of low temperature solar thermal electric generation with organic Rankine cycle in different areas[J].Applied Energy,2010,87(11):3355-3365.
[3]TIAN Y,ZHAO C Y.A review of solar collectors and thermal energy storage in solar thermal applications[J].Applied Energy,2013,104(4):538-553.
[4]YAMAGUCHI H,ZHANG X R,FUJIMA K,et al.Solar energy powered Rankine cycle using supercritical CO2[J].Applied Thermal Engineering,2006,26(17-18):2345-2354.
[5]LOLOS P A,ROGDAKIS E D.A Kalina power cycle driven by renewable energy sources[J].Energy,2009,34(4):457-464.
[6]李惟毅,高静,李子申,等.基于经济性和第二定律效率的有机朗肯循环工质优选[J].化工进展,2016,35(2):369-375.LI Weiyi,GAO Jing,LI Zishen,et al.Working fluids optimization based on economy analysis and exergy efficiency for low-temperature organic Rankine cycle[J].Chemical Industry and Engineering Progress,2016,35(2):369-375.
[7]韩中合,潘歌,范伟,等.内回热器对低温有机朗肯循环热力性能的影响及工质选择[J].化工进展,2016,35(1):40-47.HAN Zhonghe,PAN Ge,FAN Wei,et al.Effect of internal heat exchanger on thermodynamic performance of low temperature organic Rankine cycle and working fluid selection[J].Chemical Industry and Engineering Progress,2016,35(1):40-47.
[8]LI P C,LI J,PEI G,et al.A cascade organic Rankine cycle power generation system using hybrid solar energy and liquefied natural gas[J].Solar Energy,2016,127:136-146.
[9]MICHAELIDES E E.Future directions and cycles for electricity production from geothermal resources[J].Energy Conversion and Management,2016,107:3-9.
[10]MICHAELIDES E E,SCOTT G J.A binary-flashing geothermal power plant[J].Energy,1984,9(4):323-331.
[11]DENG Y,ZHAO Y,WANG W,et al.Experimental investigation of performance for the novel flat plate solar collector with micro-channel heat pipe array(MHPA-FPC)[J].Applied Thermal Engineering,2013,54(2):440-449.
[12]朱冬生,徐婷,蒋翔,等.太阳能集热器研究进展[J].电源技术,2012,36(10):1582-1584.ZHU Dongsheng,XU Ting,JIANG Xiang,et al.Research progress on solar energy collector[J].Chinese Journal of Power Sources,2012,36(10):1582-1584.
[13]KALOGIROU S A.Solar thermal collectors and applications[J].Progress in Energy and Combustion Science,2004,30(3):231-295.
[14]LI H S,CAO F,BU X B,et al.Performance characteristics of R1234yf ejector-expansion refrigeration cycle[J].Applied Energy,2014,121:96-103.
[15]YARI M.Exergetic analysis of various types of geothermal power plants[J].Renewable Energy,2010,35(1):112-121.
[16]SARKAR J,BHATTACHARYYA S.Potential of organic Rankine cycle technology in India:working fluid selection and feasibility study[J].Energy,2015,90:1618-1625.
[17]NAFEY A S,SHARAF M A.Combined solar organic Rankine cycle with reverse osmosis desalination process:energy,exergy,and cost evaluations[J].Renewable Energy,2010,35(11):2571-2580.
[18]KALOGIROU S A,KARELLAS S,BRAIMAKIS K,et al.Exergy analysis of solar thermal collectors and processes[J].Progress in Energy and Combustion Science,2016,56:106-137.
[19]WU D,LU A,NGO T,et al.Optimisation and financial analysis of an organic Rankine cycle cooling system driven by facade integrated solar collectors[J].Applied Energy,2017,185:172-182.
[20]HUANG B J,PETRENKO V A,SAMOFATOV I Y,et al.Collector selection for solar ejector cooling system[J].Solar Energy,2001,71(4):269-274.
[21]ZHAO Y,WANG J.Exergoeconomic analysis and optimization of a flash-binary geothermal power system[J].Applied Energy,2016,179:159-170.
[22]LEMMON E W,HUBER M H,MCLINDEN M O.REFPROP,NIST Standard Reference Database 23(2013)Version 9.1[A].USA.
[23]王延欣,王令宝,李华山,等.甘孜地热发电热力计算及优化[J].哈尔滨工程大学学报,2016,37(6):873-877.WANG Yanxin,WANG Lingbao,LI Huashan,et al.Thermodynamic calculation and optimization of geothermal power generation in Ganzi[J].Journal of Harbin Engineering University,2016,37(6):873-877.