基于某百千瓦级微型燃气轮机的HAT循环热力系统设计与分析

为了研究基于微型燃气轮机的湿空气透平(humid air turbine, HAT)循环用于热电联供的热力性能,建立了某百千瓦级回热循环微型燃气轮机及其HAT循环的热力性能模型,优化了循环参数,分析了压损与换热温差对循环效率的影响,并对HAT循环热电联供效率与回热循环进行了比较分析。研究表明基于回热循环微型燃气轮机构建的HAT循环折合发电效率可以达到29.66%,比回热循环提高4.28个百分点。HAT循环的热电比范围为0～2.8,回热循环的热电比范围为0～2.4。当热电比为0～1.6时,HAT循环热电联供效率高于回热循环;当热电比为1.6～2.4时,回热循环效率高于HAT循环。本研究为HAT循环热电联供系统的设计与应用提供参考。     

微型分轴燃气轮机HAT循环性能的机理试验研究

基于微型分轴燃气轮机,通过加入饱和器,构成了微型分轴燃气轮机HAT循环性能的试验装置,并开展了HAT循环性能的机理性试验。试验结果表明,空气加湿后对循环性能有明显影响,循环比功及效率相对简单循环都有很大的提高,当加湿量达到最大的4.2%时,循环输出功率增加了16%。根据试验条件进行的模拟计算结果与试验结果能很好地吻合。在此基础上,对带有回热器的试验系统进行了模拟计算,结果显示在不改变燃气初温的情况下,由于回热器的加入使系统压力损失加大,装置比功将减少3%～10%左右;但同时耗油率下降20%～45%,效率增加了30%～80%,此时系统的性能得到了显著的提高。     

FT4000型湿空气燃机循环

据“Turbomachinery International”1993年1—2月号报道,已经发现与联合循环比较,湿空气燃气轮机(HAT)循环是一种具有高效率、低成本的生产电力方法。带有中间冷却、再热动力循环的湿空气燃机是STIG(蒸汽回注式燃气轮机)的改进与发展。通过与多级“饱和器”接触,燃机的燃烧空气被饱和。加到燃烧空气中的水蒸汽(使空气包含了约(20—40)%水蒸汽)使压气机的压缩功消耗从50%减少到约30%。省下来的20%轴输出功再加给发电机。与简单循环比较,HAT循环的中间冷却减少了压缩功,而水蒸汽增加了燃机的功率,其结果是更高的比输     

10MW级HAT循环试验系统配置与热力性能研究

HAT循环作为一种新型燃气轮机循环,具有低NO_x、高效率、灵活热电调节、启停快的特点。本文分析了以某10 MW级回热循环燃气轮机为基础,构建HAT循环热电联供特性试验系统的配置,给出了燃气轮机通流匹配、热电联供以及大范围热电比调节对燃烧室等部件的技术要求。     

带冷凝除湿的湿空气透平热电联产系统

建议了一种新的基于加湿和冷凝除湿混合循环的湿空气透平热电联产系统,可提高城市热电联产系统的发电和能源利用效率,实现燃料和热源的多样性,降低主机投资和装置回收周期。利用直接式除湿器进一步回收潜热和改善系统。基于节点能量平衡的热力性能分析方法,揭示了关键参数对系统性能影响的特性规律。分析表明:借助联合应用加湿和除湿过程,系统主机的优化压缩比可以低选,发电和热电效率相应提高,有利于实用、经济、环保地实现分布式热电联产节能工程。     

燃气轮机湿空气回注循环分析

讨论燃气轮机湿空气回注循环，提出分为内部和外部空气加湿回注循环两类。以部分空气回热回注循环（PRSTIG）为基础，分析了燃气初温、压比、回注比、回热比等参数对循环效率、比功的影响。通过对两类各相关循环的特点的比较、讨论，得出的结论是：湿空气回经循环可使功率提高10％～25％，热耗降低6％～15％，NOx排放量降低15％～50％．而且均可在现行装量上改造实施。     

简讯

关于双工质平行-复合循环热机的新消息通过余热回收蒸汽发生器吸收排气废热,从而产生蒸汽,蒸汽又回注到燃气轮机的燃烧室中,结果是空气-燃料燃烧产物和蒸汽的混合物作为工质在涡轮内膨胀做功并排出。这是双工质平行-复合循环热机的简单描述(详见本刊1986年第四、五期之专题介绍),亦称作加注蒸汽的燃气轮机(STIG发动机)。美国GE公司的付总裁,船舶及工业工程服务部总经理鲍勃·斯沫兰德说:“对LM2500 STIG和LM5000 STIG的加注蒸汽发动机已有第一个订货,发动机将由动力系统工程公司安装在加利福尼亚作热电联供装置。”GE公司称STIG发动机是GE公司船舶和工业部在航空派生的燃气轮机技术方     

工作压力对湿空气透平循环饱和器性能的影响

饱和器是湿空气透平（HAT）循环的主要部件之一,它的主要作用是加热加湿空气,从而提高整个HAT循环的效率和比功。利用IAPWS-IF97提供的水和水蒸气性质与实际气体状态方程,建立了适用高压条件下饱和器的一维传热传质数学模型;利用该模型计算了不同压力条件下的饱和器工作性能,并分析了饱和器内的传热传质过程中,饱和点的位置、出口性能参数的变化规律,以及能效值的变化,可以供饱和器的设计参考。     

闭式氦气轮机循环建模及循环特性优化分析

氦气闭式布雷顿循环可用作高温气冷堆热电转换装置，能够有效降低传统核电机组复杂程度，提升热电转换效率。为详细研究氦气闭式布雷顿循环特性，指导工程样机设计，基于Refprop提供的真实气体模型建立了简单、间冷、回热以及间冷-回热四种闭式布雷顿循环数学模型；然后通过对比分析方法，揭示了关键参数变化对循环特性的影响，重点阐述了间冷、回热器对循环性能的作用机制：1)回热器能够有效回收涡轮出口氦气热量，大幅提升循环热效率，并且能够降低系统达到最佳循环效率所需压比；2)使用间冷器虽然能够降低压缩系统功耗，但受间冷器流道内压损影响，需综合考虑系统复杂度、研制成本及循环性能等因素确定系统是否需要间冷器。     

燃气轮机的湿空气循环性能分析与试验

对燃气轮机湿空气循环的性能进行了分析,建立了湿化工质的热物性计算模型,并对基于微型分轴燃气轮机湿空气循环装置的性能进行了初步试验.试验结果表明,空气加湿后燃气轮机系统的运行性能有明显改善,与简单循环系统相比,比功和效率都有很大的提高.根据试验条件进行的模拟计算结果与试验结果能很好地吻合.     

有无后冷器的微燃气轮机HAT循环性能比较

基于某80kW微燃气轮机回热循环改造工作,比较了有后冷器和无后冷器的HAT(Humid Air Turbine)循环性能和需要增加的换热器面积。研究结果表明,对于所研究的微燃气轮机,有、无后冷器的HAT循环系统折合效率和折合输出功相当,与有后冷器的HAT循环相比,无后冷器的HAT循环湿化器更高,体积更大,但是由于省掉了后冷器,其总换热面积(后冷器、湿化器、省煤器换热面积之和)更小,即意味着其投资更低,且无后冷器的HAT循环系统结构更简单,将使系统更加紧凑且控制更容易。     

Performance analysis of open cycle gas turbines

In this study, the performance of ideal open cycle gas turbine system was examined based on its thermodynamic analysis. The effects of some parameters, such as compressor inlet temperature (CIT), pressure ratio (PR) and the turbine inlet temperature (TIT), on the performance parameters of open cycle gas turbine were discussed. The turbine net power output, the thermal efficiency and the fuel consumption of the turbine were taken as the performance parameters. The values of these parameters were calculated using some basic cycle equations and variables values of thermodynamic properties. Other variables such as lower heating value, combustion efficiency and isentropic efficiencies of compressor and turbine were assumed to be constant. The result showed that the net power output and the thermal efficiency increased by a decrease in the CIT and increase in the TIT and PR values. If it is aimed to have a high net power output and the thermal efficiency for the turbine, the CIT should be chosen as low as possible and the TIT should be chosen as high as possible. Copyright © 2008 John Wiley & Sons, Ltd.     

Modeling of natural gas fueled quadruple cycle for power applications

Performance improvement being a major need of the power sector aims at increasing efficiency, lowering air pollutants and ultimately cost. This paper explores a quadruple cycle, a hybrid of solid oxide fuel cell integrated with gas turbine, steam turbine and organic Rankine cycle totaling four cycles (SOFC-GT-ST-ORC), fueled primarily by natural gas for stationary power generation. A mathematical model of the configuration of the quadruple cycle is developed and the performance investigated through a parametric study of the thermodynamic components. The power output, efficiency and other results were validated with those found in literature. The quadruple cycle produced an efficiency of 66.1% with 1,1,1,2-tetrafluoroethane, R134a as the organic working fluid. This efficiency exceeded the performance of traditional thermodynamic cycles like single steam cycle, combined and triple cycle at similar operating conditions. Lastly, the quadruple cycle presents a potential for optimization with waste heat recovery.     

氢燃联合循环中两种回热网络的优化与比较

氢气－燃气透平联合循环中燃气透平排气的热容大于压缩空气的热容,且远大于氢气的热容。先将燃气透平的排气分流成二股并分别预热空气和氢气,再合流并加热温氢的回热网络,与燃气透平的先预热压缩空气、再热预氢的回热网络比较,有效地提高了气透平的进气温度,从而增大了联合循环的比输出功,提高了联合循环的热效率和降低了燃料氢的耗量。本文用过程能量组合方法对两回热网络进行了优化分析,并定量比较了采用两种优化后的回热网     

Candidate radial-inflow turbines and high-density working fluids for geothermal power systems

Optimisation of Organic Rankine Cycle (ORCs) for binary-cycle geothermal applications could play a major role in determining the competitiveness of low to moderate temperature geothermal resources. Part of this optimisation process is matching cycles to a given resource such that power output can be maximised. Two major and largely interrelated components of the cycle are the working fluid and the turbine. Both components need careful consideration: the selection of working fluid and appropriate operating conditions as well as optimisation of the turbine design for those conditions will determine the amount of power that can be extracted from a resource. In this paper, we present the rationale for the use of radial-inflow turbines for ORC applications and the preliminary design of several radial-inflow machines based on a number of promising ORC systems that use five different working fluids: R134a, R143a, R236fa, R245fa and n-Pentane. Preliminary meanline analysis lead to the generation of turbine designs for the various cycles with similar efficiencies (77%) but large differences in dimensions (139-289 mm rotor diameter). The highest performing cycle, based on R134a, was found to produce 33% more net power from a 150 °C resource flowing at 10 kg/s than the lowest performing cycle, based on n-Pentane.     

不同的燃气轮机调控方案对燃气—蒸汽联合循环电站性能的影响

以某燃气－蒸汽联合循环电站的主要配置 基础,计算并分析比较了在改变燃料 量和调节压气机可转导叶等不同调控方案对燃气－蒸联合循环各3个组成部分及总体性能的影响,从而为燃气－蒸汽联合循环电站合理选择燃气轮机调控方案提供有意义的参考。     

开式燃气轮机中冷回热再热循环功率和效率优化

建立了开式燃气轮机中冷回热再热（ICRR）循环有限时间热力学模型,导出了循环功率和效率解析式,优化了气流沿通流部分的压降（或低压压气机进口空气质量流率）和中间压比,得到最大功率;并在给定燃油流率的情况下,优化了气流沿通流部分的压降和中间压比,得到最大热效率,进一步在给定低压压气机进口和动力涡轮出口总面积的情况下,优化两者面积分配比,得到双重最大热效率.     

A critical assessment of thermo‐economic analyses of different air bottoming cycles for waste heat recovery

Steam turbine cycle's low operating temperature makes it suitable for waste heat recovery applications. Even though conventional combined cycles, ie, topping gas turbine and bottoming steam turbine cycles, are thermodynamically efficient, they are not the most economical alternatives for power generation with capacities less than 50 MWe. A recently proposed alternative is to utilize a bottoming gas turbine cycle in form of an air bottoming cycle. In this study, an overview of air bottoming cycle is presented. Based on the discussed studies, it is decided to further evaluate the merits of water injection in the bottoming cycle air stream by using either a humidifier or an air saturator. Thermo‐economic analysis and optimization are performed to evaluate simple and water injected air bottoming cycles against steam bottoming cycles. Results indicate that conventional combined cycles can achieve the highest thermal efficiency of about 48%. While water injected air bottoming cycle with air saturator is the most cost effective combined cycle configuration and most efficient air bottoming cycle with levelized cost of electricity and energy efficiency of 64.41 US$/MWh and 39%–40%, respectively, followed by the water injected air bottoming cycle with humidifier and simple air bottoming cycle with reported levelized cost of electricity of 65.75 US$/MWh, 66.36 US$/MWh, respectively. Steam bottoming cycle has the highest levelized cost of electricity of 68.88 US$/MWh.     

Integrated solar combined cycle system with steam methane reforming: Thermodynamic analysis

The present paper considers an integrated solar combined cycle system (ISCCS) with an utilization of solar energy for steam methane reforming. The overall efficiency was compared with the efficiency of an integrated solar combined cycle system with the utilization of solar energy for steam generation for a steam turbine cycle. Utilization of solar energy for steam methane reforming gives the increase in an overall efficiency up to 3.5%. If water that used for steam methane reforming will be condensed from the exhaust gases, the overall efficiency of ISCCS with steam methane reforming will increase up to 6.2% and 8.9% for β = 1.0 and β = 2.0, respectively, in comparison with ISCCS where solar energy is utilized for generation of steam in steam turbine cycle. The Sankey diagrams were compiled based on the energy balance. Utilization of solar energy for steam methane reforming increases the share of power of a gas turbine cycle: two-thirds are in a gas turbine cycle, and one-third is in a steam turbine cycle. In parallel, if solar energy is used for steam generation for a steam turbine cycle, than the shares of power from a gas and steam turbine are almost equal.     

Development of a gas turbine performance analysis program and its application

A general-purpose performance prediction program, which can simulate various types of gas turbine such as simple, recuperative, and reheat cycle engines, has been developed. A stage-stacking method has been adopted for the compressor, and a stage-by-stage model including blade cooling has been used for the turbine. The combustor model has the capability of dealing with various types of gaseous fuels. The program has been validated through simulation of various commercial gas turbines. The simulated design performance has been in good agreement with reference data for all of the gas turbines. The average deviations of the predicted performance parameters (power output, thermal efficiency, and turbine exhaust temperature) were less than 0.5% in the design simulations. The accuracy of the simulation of off-design operation was also good. The maximum root mean square deviations of the predicted off-design performance parameters from the reference data were 0.22% and 0.44% for the two simple cycle engines, 0.22% for the recuperative cycle engine, and 0.21% for the reheat cycle engine. Both the design and off-design simulations confirmed that the component models and the program structure are quite reliable for the performance prediction of various types of gas turbine cycle over a wide range of operations.