蓄热水箱水温和水箱体积对太阳能集热系统的性能影响分析

Analysis of influende of water temperature and volume of heat stroage tank on the performance of solar heat collecting system

中文关键词: 蓄热水箱  太阳能集热系统  集热器功率  数值模拟  TRNSYS

中文摘要:

      采用实验和模拟计算方法对太阳能集热系统蓄热水箱的水温和水箱体积影响因素开展探究，分析日有用得热量、集热器功率和水箱内平均温度等参数随水箱初始温度和水箱体积的变化规律。研究结果表明：水箱初始温度从10.34℃增加到29.88℃时，日有用得热量减少了19.52%；换算成日太阳辐照量为17MJ/m2时的储热水箱中水的温升值下降了17.66%，储热水箱结束水温下降了10.73%；单位面积日有用得热量减少了17.64%。通过TRNSYS模拟软件，分析出太阳能集热系统全年运行工况时的水箱变量参数对系统性能的影响，获得了日有用得热量、集热器功率和水箱内平均温度的变化规律。通过选取不同月份的若干个时段进行对比分析，得出水箱体积对太阳能供热系统的影响较水箱初始温度大；当下调水箱初始温度和缩小水箱体积时，日有用得热量提升，但集热器功率降低；当上调水箱初始温度和缩小水箱体积时，水箱内平均温度升高；且随着太阳能集热系统运行时间的累加，水箱初始温度和水箱体积对上述各性能参数的影响减弱。日有用得热量、集热器功率和水箱内平均水温随着季节变化明显，秋季和冬季气候下的日有效得热量，集热器功率和水箱内平均水温均低于春季和夏季。

英文摘要:

      Theinfluencingfactorsofthewatertemperatureandthevolumeofthestoragewatertankof thesolarheatcollectionsystemwereexploredexperimentallyandsimulated.Theparameterssuchas thedailyusefulheatgain,collectorpowerandtheaveragetemperatureintheheatstoragewatertank changingwiththeinitialtemperatureandvolumeofthewatertankwereanalyzed.Theresultsshowed that,whentheinitialtemperatureoftheheatstoragewatertankincreasedfrom10.34to29.88℃, thedailyusefulheatgaindroppedby19.52%.Whenthedailysolarirradiationwasconvertedto17.00 MJ/m2,theratioofwatertemperaturerisingintheheatstoragetankdecreasedby17.66%,andthe watertemperatureattheendoftheheatstoragetankdecreasedby10.73%,moreover,thedaily usefulheatgainperunitareadecreasedby17.64%.TRNSYSsimulationsoftwarewasusedtoanalyze theinfluenceofthevariableparametersoftheheatstoragewatertankontheperformanceofthesolar heatcollectionsystemattheoperatingconditionofawholeyear,andthevariationrulesofthedaily usefulheatgain,thecollectorpowerandtheaveragetemperatureintheheatstoragewatertankwere obtained.Byselectingseveralperiodsindifferentmonthsthecomparativeanalysiswasfinishedthat theinfluenceofthetankvolumeonthesolarheatingsystem wasgreaterthantheinitialwater temperatureofthetank.Whentheinitialwatertemperatureofthetankandthevolumeofthewater tankwerereduced,thedailyusefulheatwasincreased,butthecollectorpowerwasdecreased.When theinitialwatertemperatureofthetankwasincreasedandthevolumeofthewatertankwasreduced, theaveragetemperatureinthewatertankcouldbeincreased.Withtheaccumulationoftheoperating timeofthesolarheatcollectingsystem,theinfluencesoftheinitialwatertemperatureandvolumeof thewatertankontheaboveperformanceparameterswereweakened.Thedailyeffectiveheatgain, collectorpowerandaveragewatertemperatureintheheatstoragewatertank weresignificantly changingwiththeseasons.Theyarelowerinautumnandwinterthaninspringandsummer.