【作者】 万逵芳；

【导师】 肖云汉； 张士杰；

【作者基本信息】 中国科学院研究生院（工程热物理研究所） ， 工程热物理， 2009， 博士

【摘要】 湿空气透平(HAT)循环是一种高效、洁净的先进动力循环，具有最高发电效率的潜力，在中小功率范围有着广阔的发展空间。随着分布式供能系统的发展，近年来微小型HAT循环受到越来越多的关注，逐步进入工业试验阶段。但迄今为止，通过系统配置提高微小型HAT循环性能的研究还非常有限。针对这一问题，本文通过参数优化，研究了不同系统结构以及与逆Brayton循环(Inverted Brayton Cycle，简称IBC)集成等因素对微小型HAT循环性能的影响，探求提高微小型HAT循环性能的系统配置。最后，结合微小型HAT循环应用领域，在考虑部分负荷、环境温度、运行模式影响的基础上，对以微小型HAT循环为主机的分布式联供系统在典型热(冷)电负荷需求下的应用进行了初步研究。主要工作及结果如下：(1)通过对不同水回路结构、不同排烟方式以及采用部分湿化的微小型HAT循坏的参数优化，确定省煤器入口补水的微小型部分空气湿化循环供电效率最高，高于全部空气湿化HAT循环供电效率约0．2个百分点。最佳空气湿化比例在0．46～0．65之间，并随初温升高而上升。与相同初温回热循环相比，最佳压比显著上升，使间冷成为可能。若采用间冷可以提高供电效率2个百分点以上。(2)微小型HAT循环和IBC底循环结合而成的复合循环(本文简称BAHAT循环)相当于增加一次间冷。与有间冷微小型HAT循环相比，BAHAT循环供电效率提高0．4～0．6个百分点以上；最佳压比、水回收率和比功都略有提高；后冷器、湿化器和透平高温段工作压力降低2～3倍，对机组寿命和安全运行非常有利。因烟气温度较低引起相对压缩耗功的降低以及压比增加引起透平出力的上升是循环性能改善的主要原因。(3)不同排烟方式对HAT循坏性能影响的研究表明，具有合适压比的引风机排烟HAT循环与直接排烟法和烟气回热法HAT循环相比，供电效率提高1到1．5个百分点。原因在于前者充分利用了水回收后烟气温度低的特点，降低了压缩耗功。在引风机出口增加水回收器可以保证水回收率。引风机最佳压比范围在1．5～1．6之间。(4)同回热循环相比，由于余热回收利用，HAT循环部分负荷下仍能保持较高的供电效率。随着环境温度的升高，虽然压气机流量下降，但加湿量的增加在一定程度上缓解了透平工质流量的降低。因此，环境温度升高对HAT循环性能影响并不显著。(5)HAT循环可以采用回热循环和注水循环模式运行，在更大的范围内提供灵活的热电负荷并保证足够高的排烟温度，满足制冷需要。解决了纯HAT循环余热无法供冷的问题。(6)以微小型HAT循环为主机的联供系统在典型建筑物中的应用研究表明，除冬季热电联供外，夏季通过运行模式的改变可实现冷电联供。与以简单循环燃机为主机的联供系统相比，前者在运行费用、一次能源利用效率方面具有优势。上述结论，可为微小型HAT循环流程设计以及HAT循环分布式供能系统配置和优化运行提供参考。更多还原

【Abstract】 Wan Kuifang (Engineering Thermophysics)Directed by Xiao Yunhan and Zhang ShijieHumid air turbine (HAT) cycle,an advanced,efficient and clean dynamic cycle,haspotential of highest electrical efficiency and a spacious foreground in medium-small powerrange.As the development of decentralized energy system (DES),small HAT has beenpaid more and more attention and industrial test has begun.However,seldom studies aboutsmall HAT cycle focused on performace enhancement by configuration adjustment so far.Therefore,performance of small HAT cycle with different configurations and integratingwith IBC ( inverted Brayton cycle) bottom cycle was studied respectively in the thesis toseek for reasonable system configuration to improve performance.Finally,application totypical heat (cooling) and electrical load of cogeneration system based on HAT cycle wereinvestigated primarily by taking consideration of part-load,environment temperature andrunning mode.The main works and conclusions are as follows:1.Parameters optimization of HAT cycle with different water circuits,exhaustdischarging methods and part-flow air humidification shows that small HAT cycle withpart-flow air humidification and makeup water entering economizer can obtain highestelectrical efficiency and slightly higher than that of full-flow air HAT cycle.The optimalpart-flow ratio is about 0.46 to 0.65 as the turbine inlet temperature (TIT) increases from950℃to 1350℃.The optimal pressure ratio grows as the TIT increases,which makes itpossible to realize intercooling in small HAT cycle and at Ieast 2 percentage pointsenhancement of electrical efficiency can be achieved if intercooling was adopted.2.The electrical efficiency of the complex cycle (so-called BAHAT in the thesis) byintegrating the small HAT cycle with IBC (Inverted Brayton Cycle) is 0.4～0.6 percentagepoints higher than that of HAT with intercooling and the working pressure of aftercooler,humidification tower and hot section of turbine is 2～3 times lower than that of the later,which is much important to life-span and safety of the unit.Reduction of relativecompression work due to low exhaust temperature and increase of turbine output becauseof the high pressure ratio are the main factors of the performance enhancement.3.Performances of HAT cycle with different exhaust discharging methods show that electrical efficiency of HAT cycle with induced draft fan (IDF) or exhaust compressor is 1to 1.5 percentage points higher than that of exhaust discharging directly and exhaustrecuperate since the former takes advantage of low exhaust temperature after waterrecovery to reduce compression work.The optimal pressure ratio of IDF is about 1.5～1.6and it’s better to put another condenser after the IDF to hold water recovery ratio.4.Comparing with recuperative cycle,high electrical efficiency can be obtained atpart load because of the heat recovery.The increase of humid rate makes the cycleunsensitive to environmental temperature rising.5.HAT cycle can run as recuperative cycle or water injected cycle in summer tosupply flexible electrical and heat load and,at the same time,hold exhaust temperaturehigh enough to drive absorption chiller.The problem of heat in pure HAT cycle’s exhaustcan’t supply cooling is overcomed.6.Applying to typical buildings,cogeneration system based on small HAT cycle cansupply heat and power in winter and cooling and power in summer by changing runningmode.The system has strong adaptability to user’s load and has advantage in runningcharge and primary efficiency comparing with cogeneration system based on simple cycle.These conclusions provide references not only for small HAT cycle design but forplan and operation of cogeneration system with HAT cycle.更多还原