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.     

燃气轮机进气蓄冰冷却系统的运行优化

燃气轮机的输出功率受环境温度的影响,对燃气轮机的进口空气进行冷却,能提高其输出功率。当前工程中采用的是在夜间用电低谷期制冰蓄冷,白天用电高峰期融冰供冷保证最大出力的运行方式。本文在采用冰蓄冷的基础上,引入时间变量建立燃料消耗最少的积分型性能指标,在时变环境的意义下,对燃气轮机进气蓄冰冷却系统提出基于用户负荷和环境温度预测曲线的新的运行优化方式,并考虑负荷预测的不确定。通过建模仿真表明这一技术可行,具有进一步研究的价值。     

燃气轮机压气机喘振及其控制算法

压气机是燃气轮机的三大部件之一,它运行的安全、高效对燃气轮机性能至关重要。本文扼要地介绍了压气机喘振的影响因素,分析了压气机的性能曲线和喘振线;在此基础上针对压气机某一种喘振控制策略,分析其各种控制设定曲线和控制算法。通过以上两方面的介绍,希望对燃气轮机压气机的喘振防治有所帮助。     

Analysis of internal cooling geometry variations in gas turbine blades

The present investigation analyzes the effects of major geometrical modifications to the interior of a convection cooled gas turbine rotor blade. The main focus lies on the flow of the leading edge channels and the impact on the heat transfer. An experimental approach is performed with flow visualization via paint injection into water. Also numerical calculations are carried out in two sets, on the one hand water calculations accompanying the experiments and on the other hand conjugate heat transfer calculations under realistic engine conditions. The latter calculations are still ongoing delivering preliminary results. Five geometry configurations are investigated, three of them with differing turbulator arrangements in the leading edge channels. The operating point of the base configuration is set to Re = 50,000 at the inlet while for the modified geometries the pressure ratio is held constant compared to the base.     

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。     

Mist film cooling simulation at gas turbine operating conditions

Air film cooling has been successfully used to cool gas turbine hot sections for the last half century. A promising technology is proposed to enhance air film cooling with water mist injection. Numerical simulations have shown that injecting a small amount of water droplets into the cooling air improves film-cooling performance significantly. However, previous studies were conducted at conditions of low Reynolds number, temperature, and pressure to allow comparisons with experimental data. As a continuous effort to develop a realistic mist film cooling scheme, this paper focuses on simulating mist film cooling under typical gas turbine operating conditions of high temperature and pressure. The mainstream flow is at 15 atm with a temperature of 1561 K. Both 2D and 3D cases are considered with different hole geometries on a flat surface, including a 2D slot, a simple round hole, a compound-angle hole, and fan-shaped holes. The results show that 10–20% mist (based on the coolant mass flow rate) achieves 5–10% cooling enhancement and provides an additional 30–68 K adiabatic wall temperature reduction. Uniform droplets of 5–20 μm are used. The droplet trajectories indicate the droplets tend to move away from the wall, which results in a lower cooling enhancement than under low pressure and temperature conditions. The commercial software Fluent is adopted in this study, and the standard k–ε model with enhanced wall treatment is adopted as the turbulence model.     

M701F型燃气轮机中的冷却技术

本文介绍了M701F型燃气轮机冷却系统的组成、日本三菱公司在F系列或G系列燃气轮机上所采用的冷却技术及其应用情况,阐明了三菱公司研发的大型燃气轮机之所以能够安全稳定运行并具有很高的可靠性和热效率,采用先进的冷却技术是其成功的重要因素之一。     

燃气轮机内环水余热回收研究

通过对燃机内环水所携带热量的研究,设计换热器,论证了用内环水加热燃机天然气进气的可行性,从而达到回收内环水余热,节约能源的目的。     

燃气透平在大型乙烯改造中的应用

本文在对某常规68万t/a乙烯裂解装置的蒸汽平衡进行分析的基础上,结合乙烯装置的改造实际情况,提出了燃气透平、废热锅炉和蒸汽透平相组合的联合循环热功联产系统,并对燃汽蒸汽联合循环与过程的能量集成进行了全局夹点分析和联合系统的技术经济分析,结果表明改造后经济效益较为明显。     

闭式循环气轮机装置使用的无气体产生燃料

无气体产生燃料在AIP装置上的应用具有优势,如不会释放燃烧反应气体,不存在燃烧产物排放问题,不会形成排气尾迹。针对闭式循环气轮机装置使用的无气体产生燃料,提出了无气体产生燃料及其氧化剂选择和需满足的技术要求,给出了一些无气体产生燃料及其相应氧化剂的种类和性质,介绍了无气体产生燃料的燃烧方式和燃烧设备,描述了使用无气体产生燃料的闭式循环蒸汽轮机装置和燃气轮机装置的系统组成及工作原理,并对一些应用上问题进行了分析。     

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.     

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。     

PG6581B型燃气轮机冷却空气信息推测

作为建立燃用低燃值合成气燃气轮机变工况模型的一个关键步骤,本文对PG6581B燃气轮机冷却空气参数及其分配进行了研究,从公开发表的净功率、效率、排气温度等数据中推测出冷却空气量的分配规律,并利用文献中GE公司F级压气机特性曲线计算简单循环变工况性能,结果与实测数据基本吻合。     

CO2应用于燃机进口空气冷却的实验研究

运用CO2作冷却介质建立高低压闭式循环系统是对燃气轮机预冷的一种尝试。针对某自备电厂联合循环机组的实际情况,设计搭建了一套实验系统。本文主要介绍了实验装置的结构尺寸、数据采集控制系统以及实验数据处理方法。通过实验,验证了该套冷却设备对于燃机进口空气的冷却效果,并达到实际燃气轮机压缩机进口空气冷却的工作要求。     

Film cooling performance of converging slot-hole rows on a gas turbine blade

Experimental tests have been performed to investigate the film cooling performance of converging slot-hole (console) rows on the turbine blade. Film cooling effectiveness of each single hole row is measured under three momentum flux ratios based on the wide-band liquid crystal technique. Measurements of the cooling effectiveness with all the hole rows open are also carried out under two coolant–mainstream flux ratios. Film cooling effectiveness of cylindrical hole rows on the same blade model is measured as a comparison. The results reveal that the trace of jets from both consoles and cylindrical holes is converging on the suction surface and expanding on the pressure surface by the influence of the passage vortex, while the influence of passage vortex on the jets from consoles is weaker. The film coverage area and the film cooling effectiveness of single/multiple console row(s) are much larger than those of single/multiple cylindrical hole row(s). When the console row is discrete and the diffusion angle of the console is not very large, the adjacent jets cannot connect immediately after ejecting out of the holes and the cooling effectiveness in the region between adjacent holes is relatively lower. On the pressure surface, the film cooling effectiveness of console rows increases notably with the increasing of momentum flux ratio or coolant–mainstream flux ratio. But on the suction side, the increase in cooling effectiveness is not very notable for console row film cooling as the coolant flux increases. Moreover, for the film cooling of single console row at the gill region of the suction surface, the jets could lift off from the blade surface because of the convex geometry of the suction surface.     

发电用单轴燃气轮机动态模型研究

以某发电用单轴燃气轮机的控制系统为原型,利用Matlab／Simulink对该型单轴燃气轮机控制系统进行了仿真,仿真结果与实际物理过程相吻合,说明此模型可以用于单轴燃气轮机及其控制系统的研究。     

Flow structure and heat exchange analysis in internal cooling channel of gas turbine blade

This paper presents the study of the flow structure and heat transfer, and also their correlations on the four walls of a radial cooling passage model of a gas turbine blade. The investigations focus on heat transfer and aerodynamic measurements in the channel, which is an accurate representation of the configuration used in aeroengines. Correlations for the heat transfer coefficient and the pressure drop used in the design of radial cooling passages are often developed from simplified models. It is important to note that real engine passages do not have perfect rectangular cross sections, but include corner fillet, ribs with fillet radii and special orientation. Therefore, this work provides detailed fluid flow and heat transfer data for a model of radial cooling geometry which possesses very realistic features.     

Comparative performance analysis of cogeneration gas turbine cycle for different blade cooling means

The paper compares the thermodynamic performance of MS9001 gas turbine based cogeneration cycle having a two-pressure heat recovery steam generator (HRSG) for different blade cooling means. The HRSG has a steam drum generating steam to meet coolant requirement, and a second steam drum generates steam for process heating. Gas turbine stage cooling uses open loop cooling or closed loop cooling schemes. Internal convection cooling, film cooling and transpiration cooling techniques employing steam or air as coolants are considered for the performance evaluation of the cycle. Cogeneration cycle performance is evaluated using coolant flow requirements, plant specific work, fuel utilisation efficiency, power-to-heat-ratio, which are function of compressor pressure ratio and turbine inlet temperature, and process steam drum pressure. The maximum and minimum values of power-to-heat ratio are found with steam internal convection cooling and air internal convection cooling respectively whereas maximum and minimum values of fuel utilisation efficiency are found with steam internal convection cooling and closed loop steam cooling. The analysis is useful for power plant designers to select the optimum compressor pressure ratio, turbine inlet temperature, fuel utilisation efficiency, power-to-heat ratio, and appropriate cooling means for a specified value of plant specific work and process heating requirement.     

Thermoeconomic optimization of an ice thermal storage system for gas turbine inlet cooling

The gas turbine power output and efficiency decrease with increasing ambient temperature. With compressor inlet air cooling, the air density and mass flow rate as well as the gas turbine net power output increase. The inlet cooling techniques include vapor or absorption refrigeration systems, evaporative cooling systems and thermal energy storage (TES) systems. In this paper the thermoeconomic analysis of ice (latent) thermal energy storage system for gas turbine inlet cooling application was performed. The optimum values of system design parameters were obtained using genetic algorithm optimization technique. The objective function included the capital and operational costs of the gas turbine, vapor compression refrigeration system, without (objective function I) and with (objective function II) corresponding cost due to the system exergy destruction. For gas turbines with net power output in the range of 25-100 MW, the inlet air cooling using a TES system increased the power output in the range of 3.9-25.7%, increased the efficiency in the range 2.1-5.2%, while increased the payback period from about 4 to 7.7 years.     

板翅式换热器在燃气轮机进气冷却系统中的应用

将板翅式换热器应用于吸收式燃气轮机进气冷却系统中，降低燃气轮机压缩机进口温度，提高燃气轮机高温条件下的出力，在国内尚无先例。针对板翅式换热器，简要介绍了结构、布置形式和性能。通过实测的运行数据，对板翅式换热器和管式换热器的性能进行了对比。结果表明：板翅式换热器在传热系数、体积、进气阻力等方面，性能优于管式换热器，是一种值得发展的换热设备。最后提出了该板翅式换热器在实际应用中存在的一些问题及对应的处理方法。