燃气轮机轮盘预旋冲击冷却特性研究

为提高冷却空气对涡轮轮盘的冷却效果,以某型燃气轮机低压涡轮为研究对象,提出了一种带有预旋冲击的轮盘冷却结构.当冷却空气流过该结构时,冷却空气的流动方向发生改变,提高了轮盘的换热效果,降低轮盘温度进而提高了轮盘强度储备.使用CFX有限元计算软件,对该冷却结构和轮盘进行了气-热-固耦合计算,结果表明:带有预旋冲击的冷却结构...     

某重型燃气轮机燃烧室冲击冷却特性研究

冲击冷却具有较高换热系数,在燃气轮机燃烧室得到重要应用。通过流固耦合传热(Coupled Heat Transfer,CHT)计算方法研究了冲击冷却孔排列方式、冲击高度与冷却孔径之比Z_n/D和初始横流对某重型燃机燃烧室火焰筒冲击冷却特性的影响。得到如下结论:三者对冲击换热效率均有显著影响,其中Z_n/D=3.7时,直列阵列相邻列之间的横流更规则,冷却效果优于错排阵列;当Z_n/D在2.0～6.0范围内时,随着Z_n/D的增大,冷却效率呈现先增大后减小的趋势,存在一个最佳换热范围2.7≤Z_n/D≤4.6,此时射流冷却与对流冷却匹配合理,冷却效率较高;初始横流对冲击冷却性能有很大削弱作用,应在设计时尽量避免。     

射流孔分布对径流涡轮背盘冷效均匀性的改善

由于可靠性和成本限制,微型燃气轮机涡轮冷却问题尚未形成成熟的解决方案。本文提出了一种简单、高可靠性的径流涡轮背盘冲击冷却技术,并针对由于涡壳几何周向不均匀导致的涡轮背盘冷效不均匀的问题,采用射流孔周向非均匀布置措施对其进行了改善。研究结果表明,在涡舌附近加密射流孔,使其附近对应的冷效极大和极小值均明显提升,冷效均匀性最高改善17.9%。不同非均布射流孔方案对涡轮背盘平均冷效及涡轮整机膨胀比的影响可忽略,对涡轮整机的效率影响不超过0.5%。     

某燃气轮机涡轮叶片复合冷却结构优化设计

为了提高涡轮叶片设计效率,搭建了基于一维管网理论的iSIGHT优化设计平台,获得了叶片的优化结构,并对其进行三维仿真计算分析。研究表明：优化前后叶片的气动性能变化不大,总压损失仅在端壁处略有差别;优化后涡轮叶片的壁面温度分布更加均匀,壁面的最高温度降低,温度梯度减小,最大相对温差降低10%左右;在降低叶片热应力的同时相对冷却效率提高1.0%。     

微型燃气轮机电力特性及并网研究

介绍了微型燃气轮机的电力特性,通过对其电力并网问题研究和分析,阐述了微型燃气轮机的电力并网应用,其并网不上网的发电模式不仅仅需要成熟的并网技术,还需要考虑到可能对电网产生的影响,绝不能向公用电网倒送电,所以要在并网控制线路上另外加入一套以逆功率保护为主的综合保护系统。文章并对微型燃气轮机运行模式转换的应用做简单探讨。     

微型燃气轮机技术

高效微型燃气轮机发电机组可用于航空、航天等领域,还可用于分布式发电、军用车辆辅助动力装置、车用混合动力装置等,因此研究这种动力装置有重要的实用意义。首先介绍了微型燃气轮机的发展过程,简要说明了过去40年内微型燃气轮机在结构上发生的变化,随后给出了组成微燃气轮机的关键部件在设计过程中应注意一些问题。最后回顾了国内一些研究单位在这一领域所进行的研究工作,并指出今后的努力方向和工作重点。     

进气冷却在微型燃气轮机冷、电联供系统中的应用

对进气冷却在微型燃气轮机冷、电联供系统中的应用进行了研究.提出了用联供系统生产的冷能对压气机进口空气进行冷却来改善联供系统在高温天气下性能的方法,并结合具体算例进行了分析.结果表明：进气冷却可使微型燃气轮机在环境温度升高的情况下仍能稳定在设计工况点附近运行;环境温度越高,其对微型燃气轮机性能改善的效果越明显;余热供冷功率会因冷却空气而减少,但用微型燃气轮机比进气冷却前多发的电功率来驱动电空调制冷,可补偿制冷功率损失,并使系统总的供冷功率得到很大提高;进气冷却是高温天气下提高微型燃气轮机冷、电联供系统性能的有效措施.     

低热值燃料对微型燃气轮机运行特性的影响

生物质气具有热值低、可燃成分不同的特点,这种特点导致生物质气在微型燃气轮机上的应用存在问题.为天然气设计的微型燃气轮机应用低热值燃料时,会导致工质流量和热力学特性的变化,从而导致燃气轮机运行特性的变化.为将这种低热值燃料应用于微型燃气轮机,提出了几种对微型燃气轮机进行调整和改进的方法,使微型燃气轮机能适应这种低热值的燃料.应用数学模型,计算出了在应用这些方法后对微型燃气轮机运行特性的影响.结果表明,应用低热值燃料后微型燃气轮机的运行特性会发生明显的改变,在调节和改进方法中对压气机和透平进行改进以适应新的流量匹配是最适合的方法.除匹配外,还提出了一些应用低热值燃料有待解决的问题.     

Capstone C系列微型燃气轮机特性的研究

以C200为主要研究对像,对于Capstone C系列微型燃气轮机结构原理、工作特点、性能指标等方面进行现场试验、数据分析、横向比对.Capstone C系列微型燃气轮机具有结构简单、高可靠性、启停迅速,负荷调节范围广、污染物排放低、对各种类型电网适应性强等优点.     

燃气轮机冷却技术综述

详细地阐述了对气膜冷却、内部强化换热以及热管冷却等的影响因素,目前的应用状况以及发展前景.重点集中在内部强化换热和热管冷却.本文可以使刚开始接触燃气轮机冷却技术的人员对冷却技术有个整体的了解,还可以对研究设计人员提供必要的参考依据.     

Performance characteristics and modelling of a micro gas turbine for their integration with thermally activated cooling technologies

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.     

Development of compressor for ultra micro gas turbine

The major problems for the development of an ultra micro gas turbine system were discussed briefly from thestand point of the internal flow and the performance characteristics.Following to these,the development of ultramicro centrifugal compression systems for the ultra micro gas turbine is explained with the design and the manu-facturing processes.The measured results of ultra micro centrifugal compressors are shown.     

Effect of various inlet air cooling methods on gas turbine performance

Turbine air inlet cooling is one of many available commercial methods to improve the efficiency of an existing gas turbine. The method has various configurations which could be utilized for almost all installed gas turbines. This paper presents a comparison between two commons and one novel inlet air cooling method using turbo-expanders to improve performance of a gas turbine located at the Khangiran refinery in Iran. These methods have been applied to one of the refinery gas turbines located at the Khangiran refinery in Iran. Two common air cooling methods use evaporative media or a mechanical chiller. The idea behind the novel method is to utilize the potential cooling and power capacity of the refinery natural gas pressure drop station by replacing throttling valves with a turbo-expander. The study is part of a comprehensive program with the goal of enhancing gas turbine performance at the Khangiran gas refinery. Based on the results, it is found that using turbo-expanders is the most economically feasible option and so is recommended to be utilized for improving gas turbine performance at the Khangiran refinery.     

大型燃气轮机透平冷却空气量估算

大型燃气轮机透平冷却空气量一般难以直接获得。本文从燃机总体物质与能量平衡的角度,结合透平一级静叶的冷却模型,给出了一种估算大型燃气轮机冷却空气量的方法,并对GE公司系列燃气轮机和西门子公司V94．3燃气轮机冷却空气量进行了估算。结果表明采用本文的方法估算的燃气轮机透平冷却空气量是合理的。     

冷却空气量对涡轮冷却性能影响综述

涡轮冷却技术被广泛应用于航空发动机及燃气轮机涡轮研发中,冷却空气的引气量成为影响整机效率的重要因素之一。本文基于现代燃气轮机及航空发动机涡轮叶片采用外部冷却与内部冷却结合的复合冷却的技术发展背景,综述了国内外在冷却空气量对涡轮叶片冷却性能影响方面的研究进展,分析并总结了冷却空气量对气膜冷却、交错肋冷却以及对综合冷却效率的影响规律,并对未来的研究方向给出了一定的建议。分析表明：对气膜孔形状的探索是未来气膜冷却技术研究的重点;交错肋研究主要处于定性研究阶段,对定量研究方法的探索是目前的发展趋势;对综合冷却效率的研究还处于起步阶段,未来可以从外部冷却和内部冷却之间的相互作用关系方面对综合冷却效率开展进一步的研究。     

西门子公司V94.3燃气轮机冷却空气信息推测

作为建立燃用低热值合成气的燃气轮机变工况模型的一个关键步骤，对西门子V94.3燃气轮机冷却空气参数及其分配进行了研究，试图从公开发表的燃气轮机功率、压比、排气温度、三亿透平初温等数据中推测出冷却空气量的分配规律。计算和推测所得到的冷却空气参数和分配规律与燃机净功率以及ISO温度基本吻合。     

An integrated approach for optimal design of micro gas turbine combustors

The present work presents an approach for the optimized design of small gas turbine combustors, that integrates a 0-D code, CFD analyses and an advanced game theory multi-objective optimization algorithm. The output of the 0-D code is a baseline design of the combustor, given the required fuel characteristics, the basic geometry (tubular or annular) and the combustion concept (i.e. lean premixed primary zone or diffusive processes). For the optimization of the baseline design a simplified parametric CAD/mesher model is then defined and submitted to a CFD code. Free parameters of the optimization process are position and size of the liner hole arrays, their total area and the shape of the exit duct, while different objectives are the minimization of NO_x emissions, pressure losses and combustor exit Pattern Factor. A 3D simulation of the optimized geometry completes the design procedure. As a first demonstrative example, the integrated design process was applied to a tubular combustion chamber with a lean premixed primary zone for a recuperative methane-fuelled small gas turbine of the 100 kW class.     

微型燃气轮机燃烧室性能影响因素的探讨

针对微型燃气轮机燃烧室性能的各种影响因素(进气条件、燃料热值、燃烧室结构等)对燃烧稳定性和燃烧效率的影响,介绍了国内外相关实验和数值模拟研究现状,分析了燃烧室主要污染物的生成机理和影响因素,以及降低氮氧化物排放浓度的技术措施。     

Evaluation of the performance of a micro gas turbine cogeneration system in a sewage treatment facility: Optimized configuration of a cogeneration system

In this study, efficient configuration of a biogas‐fuelled cogeneration system (CGS) in a sewage treatment facility was investigated. The efficient configuration of the CGS was clarified on the basis of the relationship between exhaust heat recovery efficiency (η_ehr) of the CGS and the ratio of yearly average heat demand to yearly average biogas production of the facility (Q_h.d/Q_b.p). The CGS was assumed to be used under Q_h.d/Q_b.p<η_ehr,Q_h.d/Q_b.p≈η_ehr, and Q_h.d/Q_b.p>η_ehr conditions. It was found that although the CGS was able to cover total heat demand of the facility by only consuming biogas produced, from the point of view of energy utilization, reduction of unutilized biogas and reduction of electricity demand efficiencies, the most efficient CGS was obtained under the Q_h.d/Q_b.p≈η_ehr condition. Under the Q_h.d/Q_b.p≈η_ehr condition, energy utilization, reduction of unutilized biogas, and reduction of electrical demand efficiencies were 0.64, 0.99, and 0.32, respectively, whereas under the Q_h.d/Q_b.p<η_ehr and Q_h.d/Q_b.p>η_ehr conditions, energy utilization, reduction of unutilized biogas, and reduction of electrical demand efficiencies were in ranges of 0.56–0.64, 0.43–0.99, and 0.16–0.20, respectively. A more efficient system can be obtained if a CGS with lower η_ehr such as a fuel cell is used under the Q_h.d/Q_b.p<η_ehr condition and if a CGS with higher η_ehr such as a steam turbine is used under the Q_h.d/Q_b.p>η_ehr condition. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20389