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针对某型燃气轮机环形燃烧室,通过数值模拟,对比分析了Standardk—ε、RNGk-ε、Realizable k-ε、Standard k-ω、雷诺应力五种湍流模型以及简单概率密度模型(PDF)、有限速率模型、涡耗散模型(ED)、涡耗散概念模型(EDC)四种燃烧模型对环形燃烧室性能计算的影响。结果表明:Realizable k-ε模型模拟的冷态流场与PIV试验测量结果最符合;EDC模型最能合理的模拟燃烧效果,但在预测NOx排放时不如有限速率模型精确。以上结论为后续该型号燃气轮机环形燃烧室的数值计算和设计提供了参考。 相似文献
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建立了考虑空气冷却的燃气轮机系统的变工况模型,对掺氮燃烧方式和纯氢燃烧方式下燃气轮机的变工况性能进行了计算和分析.利用Chemkin中基于氢气燃烧机理的燃烧模型,对2种燃烧方式下燃烧室内的燃烧特性进行了计算和分析,比较了燃烧区流体速度、层流火焰速度、点火延迟时间和NOx排放量.结果表明:采用纯氢燃烧方式的燃气轮机在扭矩裕度、喘振裕度和透平出口温度三方面的变工况性能都更优,但燃烧室内面临更高的回火可能性和NOx排放量. 相似文献
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燃气轮机中的燃烧反应是一种高度不可逆的过程,因此Yong效率较低。燃气轮机一燃料电池混合装置则由于绝大部分燃料通过电化学反应来释放能量,只有未完全利用的燃料参加燃烧反应。用热力学第一定律和热力学第二定律对燃气轮机和它与燃料电池构成的混合装置进行了比较分析,研究了循环的Yong效率和各部件的性能对整个系统的影响,给出了混合装置中对提高系统性能具有重要影响的部件。 相似文献
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微型燃气轮机燃烧室性能的数值研究 总被引:5,自引:0,他引:5
针对Capstone公司的C30微型燃气轮机的燃烧室,采用κ—ε湍流模型、EBU—Ambenius湍流燃烧模型描述其燃烧流动,采用扩展Zeldivch机制描述HOx生成;应用分区结构化网格和SIMPLE算法求解控制方程,进行了三维燃烧流动的数值模拟研究,同时对燃烧室的整体性能进行了分析。通过数值计算及结果分析,着重研究了环型贫燃预混燃烧室的燃烧组织形式对燃烧室性能的影响,并探讨了流动控制板对燃烧室内燃烧流动和燃烧室出口HOx分布的影响。数值研究的主要目的是配合新型微型燃气轮机的研制,获得微型燃气轮机燃烧室的设计经验,为研制既有高燃烧效率和燃烧稳定性,又有低HOx排放特性的燃烧室奠定基础。 相似文献
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燃气轮机与混合装置的[火用]性能比较 总被引:1,自引:0,他引:1
燃气轮机中的燃烧反应是一种高度不可逆的过程,因此焖效率较低。燃气轮机-燃料电池混合装置则由于绝大部分燃料通过电化学反应来释放能量,只有未完全利用的燃料参加燃烧反应。用热力学第一定律和热力学第二定律对燃气轮机和它与燃料电池构成的混合装置进行了比较分析,研究了循环的炯效率和各部件的性能对整个系统的影响,给出了混合装置中对提高系统性能具有重要影响的部件。图4表2参8: 相似文献
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The study describes a special construction of a pulsating self-compressing combustion system, which gives nearly constant in- and outflows of gas, and its use in connection with gas turbine power stations. The main idea of the self-compressing combustion chamber is that the pressure at the outflow after combustion is higher than that at the inflow to the combustion chamber. The maximum thermodynamically possible pressure rise in the combustion chamber is solved and calculated for different temperature ratios and combustion processes. The thermodynamic advantage of pulse combustion for gas turbine systems is shown as a function of the self-compression pressure ratio. 相似文献
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A novel hydrogen-fueled power plant with inherent CO2 capture based on calcium looping process is proposed in this paper. The analyzed system has been evaluated from the energy and exergy points of view, it enables determination of the contribution of main component to the total exergy loss. The results show that energy and exergy efficiencies of the system are 42.7% and 42.25% respectively, combustion chamber and regenerator are responsible for large exergy destructions, mainly due to irreversibilities associated with the combustion reactions, they have great potential for system efficiencies improvements. The effects of various air pressure ratios and gas turbine inlet temperatures on the system thermodynamic performance are also presented. The thermodynamic efficiencies increase with the increase in air pressure ratios and gas turbine inlet temperatures. 相似文献
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从燃气轮机整体性能、气路部件、滑油系统、结构振动等方面,较为全面地构建了船用三轴燃气轮机性能退化指标体系。提出了表征整机性能退化的排温裕度、热损失指标、功率不足指标、额外热功比、热效率比等指标。明确了表征气路部件退化的退化因子的概念,提出了绝热效率退化因子、流量退化因子、喘振裕度、热电偶分散度等表征压气机、涡轮、燃烧室等气路部件退化的指标。提出了构建数学模型、统计三限值法、小偏差法和卡尔曼滤波等退化指标的求解和分析方法,并进行了实例分析。为进一步开展燃气轮机性能退化状态评估构建了基本框架。 相似文献
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为确认燃烧调整过程中影响燃气轮机运行状态的主导因素,首先将影响运行状态的天然气压力、天然气温度、压气机排气温度、压气机进口温度等14个参数作为输入变量,将表征燃气轮机运行状态的功率、燃烧室、加速度、NOx质量浓度作为输出变量,建立粒子群算法优化的Elman神经网络模型,得到隐含层与输入层、输出层之间的连接权值;然后利用Olden方法处理神经网络的连接权值,获得各因素对燃气轮机运行状态影响显著性的量化值表达式,建立了燃烧调整过程中燃气轮机运行状态影响因素显著性分析的方法;最后结合燃气轮机运行数据进行计算分析。结果表明:燃气轮机的运行状态主要受排气温度、预混气压力及流量、值班气流量、压气机进口差压以及进气导流叶片开度5个因素的影响,并且燃烧调整过程中需要统筹调整输入参数,以保证燃气轮机燃烧始终处于稳定、低NOx排放区域。 相似文献
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建立了燃气轮机高温涡轮叶片损伤评估模型,包括热力学性能计算模型、应力评估模型、热评估模型和交互损伤分析模型,无法测量参数由热力学性能计算模型计算,作为应力评估模型和热评估模型的输入。根据蠕变与疲劳损伤模型分析结果,对进气道内使用喷雾冷却降温的燃气轮机高温涡轮叶片进行损伤评估,比较了燃气轮机在不同转速以及负荷下,使用喷雾冷却系统前后,高温涡轮叶片损伤的变化,定量评估喷水量对高温叶片寿命的改善。结果表明:启用喷雾冷却系统可以大幅减小因蠕变造成的叶片损伤,在低负荷(30%)时损伤减小的幅度尤为明显,其预期寿命从40 000 h延长到50 000 h以上,可以大幅延长叶片的使用寿命;在夏季运行时(53%负荷),如果以减少蠕变损伤为目标,可以考虑增加喷水量,从40%~100%,叶片各级蠕变损伤最高可减小13.5%。 相似文献
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采用基于Maisotsenko循环的露点间接蒸发式冷却作为进气冷却的手段,研究了不同环境条件下其对燃气轮机性能的提升效果。建立了针对某9E级燃气轮机的热力循环过程的计算模型,并利用该热力模型分析了进气温度变化对燃机出力的影响。基于Maisotsenko循环的原理,以温降为指标对露点间接蒸发冷却器的性能进行了分析。以功率和效率作为指标,对燃气轮机性能随环境条件的变化情况做了数值模拟,对露点蒸发式冷却与无进气冷却、直接喷雾式冷却对燃机性能的影响进行了计算分析。结果表明,在高温低湿度的条件下,露点间接蒸发式冷却能有效提升燃机性能。 相似文献
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Oscillating water column (OWC) are devices for wave energy extraction equipped with turbines for energy conversion. The purpose of the present work is to study the thermodynamic of a real gas flow through the turbine and its differences with respect to the ideal gas hypothesis, with the final goal to be applied to OWC systems. The effect of moisture in the air chamber of the OWC entails variations on the atmospheric conditions near the turbine, modifying its performance and efficiency. In this work we study the influence of humid air in the performance of the turbine. Experimental work is carried out and a real gas model is asserted, in order to take a first approach to quantify the extent of influence of the air–water vapour mixture in the turbine performance. The application of a real gas model and the experimental study confirmed the deviations of the turbine performance from the expected values depending on flow rate, moisture and temperature. 相似文献
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Thermodynamic characteristics of a low concentration methane catalytic combustion gas turbine 总被引:1,自引:0,他引:1
Low concentration methane, emitted from coal mines, landfill, animal waste, etc. into the atmosphere, is not only a greenhouse gas, but also a waste energy source if not utilised. Methane is 23 times more potent than CO2 in terms of trapping heat in the atmosphere over a timeframe of 100 years. This paper studies a novel lean burn catalytic combustion gas turbine, which can be powered with about 1% methane (volume) in air. When this technology is successfully developed, it can be used not only to mitigate the methane for greenhouse gas reduction, but also to utilise such methane as a clean energy source. This paper presents our study results on the thermodynamic characteristics of this new lean burn catalytic combustion gas turbine system by conducting thermal performance analysis of the turbine cycle. The thermodynamic data including thermal efficiencies and exergy loss of main components of the turbine system are presented under different pressure ratios, turbine inlet temperatures and methane concentrations. 相似文献
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We have developed a simple model of a micro gas turbine system operating at high ambient temperatures and characterized its performance with a view to integrating this system with thermally activated cooling technologies. To develop and validate this model, we used experimental data from the micro gas turbine test facility of the CREVER research centre. The microturbine components were modelled and the thermodynamic properties of air and combustion gases were estimated using a commercial process simulator. Important information such as net output power, microturbine fuel consumption and exhaust gas mass flow rate can be obtained with the empirical correlations we have developed in this study. This information can be useful for design exhaust gas fired absorption chillers. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献