某船燃气轮机动力涡轮转速不稳故障分析

为解决某船燃气轮机动力涡轮转速不稳故障,分析推进遥控系统对燃气轮机油门的闭环控制流程,进一步对燃油作动器、燃气发生器转速传感器、动力涡轮转速传感器、燃机电子柜的电气连接进行检查,与经验数据进行比对,并对重点部位的电气连接件进行拆检。最终结果表明,该燃气轮机动力涡轮转速不稳的原因是箱装体底部电连接器接插件瑕疵,造成接触不良。     

军工民品科技信息

陆用燃气轮机　　为国内外提供从 2 0 0 0～ 2 40 0 0 k W各种级别的燃气轮机 ,作为燃机电站的动力 ,迄今为止已成功地应用于深圳、海南、无锡、成都、敦煌等地以及邮电部门的燃机电站工程中 ,并进入国际市场。陆用燃机产品能够为“西气东输”工程增压设备以及其他独立动力工程提供理想的动力源。由成都发动机公司和美国普惠公司合作生产的FT8A燃气轮机机组 ,是油气输送管路动力专用型 ,能够适应输送管路中的各种状况变化需求 ,功率最大可达 2 60 0 0 k W,动力涡轮可正反向转动 ,带泵热效率可达 3 8.9% ,并备有双燃料系统 ,油气皆可。地　…     

电动汽车微型燃气轮机增程器向心涡轮设计方法研究

本文首先通过匹配计算确定了微型燃气轮机增程器的主要性能指标,并通过模型分析得到微型向心涡轮的设计参数;其次根据向心涡轮工作过程建立损失模型,将遗传算法融入设计方案,编制了设计流程和计算程序;最后依据设计结果完成了微型向心涡轮结构设计,并利用CFD方法进行数值模拟计算。仿真计算结果表明：所设计的微型向心涡轮的轮周效率、轴效率以及输出功率均达到了设计要求,同时内部流场模拟结果显示涡轮也具有较好的气动性能,说明所采用的设计方法是可靠的。     

考虑真实粗糙表面的燃机球轴承磨损与混合润滑耦合机理

船舰燃机轴承服役环境苛刻,工作界面难以建立全膜润滑状态,局部粗糙峰接触发生磨损,而磨损又会通过影响表面形貌反作用于界面混合润滑状态,影响轴承摩擦学特性。目前,面向燃气轮机滚动轴承,开展考虑真实表面粗糙度的磨损与混合润滑状态耦合作用的研究仍然很少。因此,以燃气轮机涡轮端球轴承为对象,综合考虑接触界面磨损、弹性变形与实测机械表面粗糙度影响,建立滚动体与内滚道三维磨损区域下的润滑-接触数值分析模型,研究低速、重载及滑滚苛刻条件下轴承摩擦磨损特性。     

空气涡轮机带负载启动过程仿真

涡轮泵发射系统是目前世界上海军现役潜艇最先进的液压平衡式深水发射装置.空气涡轮机是涡轮泵发射系统的动力核心.为深入研究该涡轮机的工作特性,为进一步的研发工作奠定理论基础,运用热力学、空气动力学等理论建立空气涡轮机及其辅助系统的仿真模型,根据仿真模型编制仿真软件,进行空气涡轮机启动过程的动态仿真,并对仿真结果进行析.仿真结果表明,空气涡轮机带负载的启动特性可满足涡轮泵发射系统的要求.该模型不仅可用于该涡轮机的仿真研究以摸索其工作特性,其仿真结果还可为试验样机的总体设计及其试验的提供理论依据.     

微型燃气轮机虚拟设计系统的开发与研究

在研究微型燃气轮机结构特点和虚拟设计的基础上,提出了微型燃气轮机的虚拟设计体系结构.利用计算机辅助设计技术完成了微型燃气轮机各主要结构的设计计算,应用参数化建模技术建立了微型燃气轮机实体模型,应用有限元分析方法进行了结构分析和优化.基于虚拟操作平台实现了微型燃气轮机的装配顺序规划、碰撞检测和装配仿真,从而实现了复杂产品的数字化集成设计.     

导叶间隙对变几何高压涡轮气动性能的影响

对燃气轮机的流量进行调节是保证燃气轮机各工况下均具有良好性能的一项重要措施,而变几何涡轮是实现流量调节的关键技术。采用CFD数值模拟的方法,以某真实燃气轮机第一级高压涡轮作为研究对象,采用机械式调节技术,通过改变高压涡轮导叶安装角,使其喉道面积变化,从而达到控制涡轮进口流量的目的。采用全三维流场数值模拟,系统研究了导向器有无叶尖间隙时安装角变化对涡轮气动性能影响规律。研究发现,导叶打开时,流量及效率增加,反之均降低,并且发现导叶间隙对涡轮效率有较大影响。     

迷宫密封对悬臂盘-空心转子稳定性影响与改进方法研究

面向某型船用燃气轮机动力涡轮转子,建立了悬臂盘-空心转子的动力学模型并求解其临界转速及振型,探讨了影响临界转速的因素,重点揭示了级间与叶顶迷宫密封对转子稳定性的影响规律,结果表明:迷宫密封对悬臂盘-空心转子的临界转速及振型的影响较小,但迷宫密封引起的气流激振会影响转子的稳定性.通过将迷宫密封改为蜂窝密封或减小迷宫密封进...     

基于微型自耕机混合动力控制方法及混合机械动力装置设计

为适应蔬菜大棚的大规模发展,解决农业污染,提出一种混合动力控制方法及用于微型自耕机的混合动力装置,具有操作方便、体积小、零排放的优点.分析了该设计的技术难点和解决方案;通过Simulin软件,开发氢燃料-锂离子电池混合动力系统仿真平台和分析微型自耕机的3种工作状态;运用计算机设计软件Solidworks,对微型自耕机的各个零部件进行了三维建模并进行装配;其核心零件动力制器采用凹凸方式设计.样机测试证明,微型自耕机的各项性能指标均已达到国际标准要求,整机质量为40 kg,操作灵活、转移方便、制造成本较低.     

柔性铰链位移放大机构放大能力和负载能力分析

柔性铰链具有无间隙、无摩擦和运动灵敏度高的特点,在微型机械中常用来作为位移放大器使用.在对柔性铰链进行应力分析和位移损失分析的基础上,研究位移放大机构所允许的最大输入位移,以及负载对柔性铰链放大能力的影响,分析负载与放大倍数间的关系,建立了位移放大的数学模型.     

Performance test and component characteristics evaluation of a micro gas turbine

This study aims to analyze engine performance and component characteristics of a micro gas turbine based on detailed measurement of various parameters. A test facility to measure performance of a micro gas turbine was set up and performance parameters such as turbine exit temperature, exhaust gas temperature, engine inlet temperature, compressor discharge pressure and temperature, and fuel and air flow rates were measured. The net gas turbine performance (power and efficiency based on the gas turbine shaft end) was isolated and analyzed. With the aid of measurement based simulation, component characteristic parameters such as turbine inlet temperature, compressor efficiency, turbine efficiency and recuperator effectiveness were estimated. Behaviors of the estimated characteristic parameters with operating condition change were examined and sensitivities of estimated parameters to the measured parameters were analyzed.     

Performance evaluation of a twin-shaft gas turbine engine in mechanical drive service

This study aimed at quantifying the effect of mechanical load on the performance of an 18.7 MW offshore gas turbine engine. The targeted engine is of two-shaft free power turbine configuration that operates as a mechanical driver for a process compressor in the gas compression service. The study is a part of a comprehensive performance health monitoring program to address the diagnostic and prognostic requirements in oil and gas offshore platforms and is motivated by the need to provide in-depth knowledge of the gas turbine engine performance. In this work, only the context of some design point key performance parameters and a limited set of collected operational data from the gas turbine in the real plant are available. Therefore, three major tasks, namely design point calculation, characteristic map tuning and off-design performance adaption, were needed to be performed. In order to check the validity of the proposed model, the obtained simulation results were compared with the operational data. The results indicate the maximum inaccuracy of the proposed model is 3.04 %. Finally, by employing the developed model, the engine capability for power generation when exposed to various load speeds is investigated. The obtained result demonstrates at the maximum gas generator speed, every 3 % decrease in mechanical speed leads to 1 % decline in the gas turbine power output. Moreover, when the gas turbine operates under design power load and mechanical speed is lower than 80 % of design speed, every 1 % decrease in load speed results in 0.2 % loss in thermal efficiency. The established relationship will assist proper assessment of mechanical drive gas turbines for performance health monitoring.

     

Analysis of performance deterioration of a micro gas turbine and the use of neural network for predicting deteriorated component characteristics

Deteriorated performance data of a micro gas turbine were generated and the artificial neural network was applied to predict the deteriorated component characteristics. A program to simulate operation of a micro gas turbine was set up and deterioration of each component (compressor, turbine and recuperator) was modeled by changes in the component characteristic parameters such as compressor and turbine efficiency, their flow capacities and recuperator effectiveness and pressure drop. Single and double faults (degradation of single and two parameters) were simulated. The neural network was trained with a majority of the generated deterioration data. Then, the remaining data were used to check the predictability of the neural network. Given measurable performance parameters as inputs to the neural network, characteristic parameters of each component were predicted and compared with original data. The neural network produced sufficiently accurate prediction. Using a smaller number of input parameters decreased prediction accuracy. However, an acceptable accuracy was observed even without information on several input parameters. This paper was recommended for publication in revised form by Associate Editor Ohchae Kwon Mr. J. E. Yoon received his MS degree from Dept. of Mechanical Engineering, Inha University in 2008. His thesis topic was test and simulation of micro gas turbines. He has been working at LG Digital Appliance Company. Mr. J.J. Lee received his MS degree from Dept. of Mechanical Engineering, Inha University in 2006, and is now Doctoral student at the same department. His research topics include simulation and diagnosis of gas turbines. Prof. T.S. Kim received his PhD degree from Dept. of Mechanical Engineering, Seoul Na-tional University in 1995. He has been with Dept of Mechanical Engineering, Inha Univeristy since 2000, and is Associate Professor as of Oct. 2008. His research area is aero-thermodynamc simulation and test of gas turbine systems including microturbine and their components. His recent research concern also includes analysis on fuel cells and fuel cell/gas turbine hybrid systems. Prof. J.L. Shon received his PhD degree from Dept. of Mechanical Engineering, The University of Alabama in Huntsville in 1986. He has been with School of Mechanical & Aerospace Engineering, Seoul National University since 2000, and is BK Associate Professor as of Oct. 2008. His research area is design, simulation and test of gas turbine system and components. He is also interested in researches on fuel cells and fuel cell/gas turbine hybrid systems.     

Evaluation of component characteristics of a reheat cycle gas turbine using measured performance data

In this work, component characteristics of a reheat cycle gas turbine in a commercial combined cycle power plant were evaluated. An inverse performance analysis, in which component characteristic parameters were estimated based on measured performance data, was carried out. The measured parameters were the power, the fuel flow rates of two combustors, and the temperatures and pressures at various locations such as the compressor discharge, exits of both the high-and low-pressure turbines. The estimated parameters from the analysis include the compressor and turbine efficiencies and the inlet air flow rate. The analysis was performed for a wide operation range in terms of the ambient temperature and load, providing a database for the variations of the characteristic parameters with changes in the operating condition. In addition, a sensitivity analysis was performed to examine the influence of the uncertainties of the measured parameters on the estimated parameters. The analysis program can be further developed into a performance diagnosis tool and the obtained component characteristic data can be used as reference database.     

基于数字孪生的风机实时载荷预估研究

为推动风电产业技术的持续进步,改善风机控制系统性能,利用数字孪生方式,实现风机实时载荷的预估.利用风机原有的高可靠采集信号作为输入,搭建风电机组回归模型,建立系统权重矩阵,并进行线性插值使模型适应整个发电工况,完成了风电机组载荷实时预估.载荷预估值可替代目前的应变片载荷测试系统.载荷预估经评估计算精确度在 ９６.００％ 以上.预估载荷在风机塔架推力消减实时控制系统中的应用表明,减载效果显著.     

Performance simulation of a turboprop engine for basic trainer

A performance simulation program for the turboprop engine (PT6A-62), which is the power plant of the first Korean indigenous basic trainer KT-1, was developed for performance prediction, development of an EHMS (Engine Health Monitoring System) and the flight simulator. Characteristics of components including compressors, turbines, power turbines and the constant speed propeller were required for the steady state and transient performance analysis with on and off design point analysis. In most cases, these were substituted for what scaled from similar engine components’ characteristics with the scaling law. The developed program was evaluated with the performance data provided by the engine manufacturer and with analysis results of GASTURB program, which is well known for the performance simulation of gas turbines. Performance parameters such as mass flow rate, compressor pressure ratio, fuel flow rate, specific fuel consumption and turbine inlet temperature were discussed to evaluate validity of the developed program at various cases. The first case was the sea level static standard condition and other cases were considered with various altitudes, flight velocities and part loads with the range between idle and 105% rotational speed of the gas generator. In the transient analysis, the Continuity of Mass Flow Method was utilized under the condition that mass stored between components is ignored and the flow compatibility is satisfied, and the Modified Euler Method was used for integration of the surplus torque. The transient performance analysis for various fuel schedules was performed. When the fuel step increase was considered, the overshoot of the turbine inlet temperature occurred. However, in case of ramp increase of the fuel longer than step increase of the fuel, the overshoot of the turbine inlet temperature was effectively reduced.     

水下航行器燃气涡轮动力系统的总体优化设计

通过分析水下航行器燃气涡轮机主要结构参数对发动机性能的影响,给出了涡轮动力系统主要结构参数优化的数学模型,对单级、冲动式（带小反力度）、超音速和多速制的燃气涡轮机的设计实例运用遗传算法进行了多目标函数优化设计计算。     

水下航行器燃气涡轮动力系统的多目标函数优化

通过分析水下航行器燃气涡轮机主要结构参数对发动机性能的影响,给出了涡轮动力系统主要结构参数优化的数学模型,对单级、冲动式(带小反力度)、超音速、多速制的燃气涡轮机的设计实例运用遗传算法进行了多目标函数优化设计计算。     

点火角对小排量增压汽油机燃烧特性的影响研究

对465Q汽油机进行废气涡轮增压改造,研究点火角对增压后发动机燃烧特性的影响。随点火角的增大,缸内最高压力和压升率峰值都增大,其对应的曲轴转角提前,燃烧循环变动改善;每个工况下,都存在一个最佳的点火角,使发动机的功率最大,燃油消耗率最低。在最佳点火角附近,点火角每调整5°,动力性和经济性变动幅度在4%左右。     

Influence of steam injection through exhaust heat recovery on the design performance of solid oxide fuel cell — gas turbine hybrid systems

This study analyzed the influence of steam injection on the performance of hybrid systems combining a solid oxide fuel cell and a gas turbine. Two different configurations (pressurized system and ambient pressure system) were examined and the effects of injecting steam, generated by recovering heat from the exhaust gas, on system performances were compared. Performance variations according to the design of different turbine inlet temperatures were examined. Two representative gas turbine pressure ratios were used. Without steam injection, the pressurized system generally exhibits higher system efficiency than the ambient pressure system. The steam injection augments gas turbine power, thus increasing the power capacity of the hybrid system. The power boost effect due to the steam injection is generally greater in the relatively higher pressure ratio design in both the pressurized and ambient pressure systems. The effect of the steam injection on system efficiency varies depending on system configurations and design conditions. The pressurized system hardly takes advantage of the steam injection in terms of system efficiency. On the other hand, the steam injection contributes to the efficiency improvement of the ambient pressure system in some design conditions. In particular, a higher pressure ratio provides a better chance of efficiency increase due to the steam injection. This paper was recommended for publication in revised form by Associate Editor Kyoung Doug Min Mr. S. K. Park received his MS degree from Dept of Mechanical Engineering, Inha University in 2007, and is now Doctoral student at the same department. His research topics include performance analysis of fuel cell and fuel cell/gas turbine hybrid sys-tem and advanced energy systems. Prof. T. S. Kim received his PhD degree from Dept of Mechanical Engineering, Seoul National University in 1995. He has been with Dept of Mehanical Engineering, Inha University since 2000, and is Associate Professor as of Nov. 2008. His research area includes simulation and test of gas turbines and aerodynamic performance of their components. He is also interested in researches on fuel cells and fuel cell/gas turbine hybrid systems. Prof. J. L. Sohn received his PhD degree from Dept of Mechanical Engineering, The University of Alabama in Huntsville in 1986. He has been with School of Mechanical & Aerospace Engineering, Seoul National University since 2000, and is BK Associate Proessor as of Nov. 2008. His research area is design, simulation and test of gas turbine system and components. He is also interested in researches on fuel cells and fuel cell/gas turbine hybrid systems.