变几何多级轴流压气机全工况性能预测模型

基于压气机级的综合特性曲线,采用逐级叠加法开发了静叶可调的变几何多级轴流压气机全工况性能预测模型。在计算中将低转速下不同的级特性曲线分别应用于压气机各级,建立每一级的性能计算模块;在合理假设的基础上,根据动叶速度三角形推导出压气机入口可调静叶(IGV)角度变化对压气机性能的影响;引入气体动力学函数和变比热计算公式,简化了计算,提高了模型精度。算例表明,本模型具有一定的适用性,基本上反映出压气机的全工况特性,较准确地体现了IGV调节对整台压气机性能的影响,为开发现代大型燃气轮机动态仿真模型提供较可靠的压气机性能计算数据。     

PG9171E型燃气轮机变工况计算模型的建立

为了建立PG9171E型燃气轮机变工况计算模型,必须根据电厂提供的原始数据建立该机型的压气机特性.由于现有基线估算方法的建立未包含高压比压气机实验数据.故一般只被应用于压比小于11的压气机特性估算,而PG9171E型燃气轮机的压气机压比已接近12.为了解决这个问题,在压气机特性计算过程中首次提出分段计算法,计算结果表明:该方法的精度能够满足实际应用要求.在变工况计算模型的燃气热力性质计算方面,根据热力性质表[2].归纳出空气、CH2燃气、C燃气和水蒸气的热力性质通用关系式,简化了燃烧室燃用重油时的湿燃气焓值和对数压比值的计算过程,变工况计算模型的计算结果与燃气轮机实测参数进行比较,表明上述改进方法在实际应用中能够满足建模精度的要求.     

注蒸汽对涡轮增压器的影响

水蒸气与燃气混合后的混合气体注入涡轮后,涡轮增压器会出现运行状态的变化。经对注蒸汽后的涡轮增压器进行了热力学的分拆,认为：汽气比的增大使增压器的转速、压气机空气流量和压气机压比增高;注汽温度对压气机压比有较小影响;低工况时,水蒸气的注入使涡轮的折合流量、膨胀比皆增大;在高工况时,膨胀比、折合流量能够增大的幅度减小：不同的汽气比对涡轮效率特性曲线影响较小。     

双压再热蒸汽循环的IGCC变工况性能

介绍了IGCC蒸汽侧采用双压再热循环时再热回路的合理选定。叙述了IGCC的变工况模型和计算得到的变工况性能及其分析,指出调节压气机IGV时,能与一般联合循环一要改善IGCC的变工况性能。     

燃气轮机涡轮特性计算方法

介绍一种计算燃气轮机涡轮变工况特性的方法，给出了主要公式、主要公式的推导、计算表格和气体动力函数的主要公式。采用气体动力函数为工具便于实现计算机编程。特性用折合参数形式表达，可通用于涡轮各种工况。与压气机特性一起可完成燃气轮机联合工作线计算，确定启动过程和变负荷特性，对于设计新的燃气轮机和研究在运的燃气轮机是必不可少的。本方法曾用于工厂燃气轮机设计计算。     

燃气轮机调节方式对IGCC系统变工况性能的影响

为选择合理的燃气轮机调节方式,采用Thermoflex软件建立了200 MW级IGCC系统模型,从系统的角度出发比较研究了燃气轮机的调节方式对燃气顶循环系统、蒸汽底循环系统和整个IGCC系统变工况性能的影响.研究表明:与压气机可转导叶(IGV)不调相比,IGV可调时更有利于提高系统的变工况性能.等燃气透平初温(T3)调...     

简单循环燃气轮机系统建模及其变工况性能分析

以PG6541B燃气轮机为研究对象，充分利用已公开的燃气轮机数据，探讨了简单循环燃气轮机设计工况和变工况下建模的方法。用半经验公式，对冷却空气量的分配进行了计算。利用基元叶栅法，计算得到了压气机的通用特性曲线。分析了燃烧室喷水对燃气轮机性能的影响。图7表2参9     

基于IGV控制的先进燃气轮机联合循环运行优化

为了达到高效的先进燃气轮机联合循环优化运行,提高循环的能源利用率,以先进燃气轮机联合循环技术为研究对象,通过以有机物为工质的朗肯循环回收燃气轮机的余热,进行燃气轮机联合循环变工况仿真模拟来研究联合循环运行特性,分析了环境温度和压气机进口导叶(IGV)调节对联合循环运行特性的影响,制定了IGV角度的优化控制策略。结果表明:在变负荷工况和不同环境温度下,调节燃气轮机的空燃比,可以优化该燃气轮机联合循环的运行特性,提升联合循环效率。     

某型多级轴流压气机三维CFD流场分析及气动优化

以某11级轴流压气机为研究对象,通过三维计算软件对某型压气机整机建模及流场进行了数值模拟,分别计算了设计工况、变工况及改变导叶安装角等工况的特性,得到了压气机流量－压比特性曲线、流量－效率特性曲线,与压气机的性能试验数据进行了对比,其误差在可允许范围内.同时对压气机的每一级的数据行了分析,总结了该压气机的气动设计规律.通过流场分析得到出口导叶的流场分布不合理的结论,并通过对其母型机的流场分析,提出了改进的方案.这些工作对压气机的设计开发提供了宝贵经验.     

基于经验方程的船用三轴燃气轮机压气机特性计算

针对在压气机特性拟合计算中存在的部件特性不完整问题,提出一种基于经验方程的船用三轴燃气轮机压气机特性计算方法。通过经验方程的引入,求解出所缺少的高压压气机特性方程,继而建立了完整的压气机特性计算模型。分析表明该模型具有较高的精确度,能够满足船用三轴燃气轮机压气机变工况特性计算的需要。     

Improvement of part-load performance of gas turbine by adjusting compressor inlet air temperature and IGV opening

A novel adjusting method for improving gas turbine (GT) efficiency and surge margin (SM) under part-load conditions is proposed. This method adopts the inlet air heating technology, which uses the waste heat of low-grade heat source and the inlet guide vane (IGV) opening adjustment. Moreover, the regulation rules of the compressor inlet air temperature and the IGV opening are studied comprehensively to optimize GT performance. A model and calculation method for an equilibrium running line is adopted based on the characteristic curves of the compressor and turbine. The equilibrium running lines calculated through the calculation method involve three part-load conditions and three IGV openings with different inlet air temperatures. The results show that there is an optimal matching relationship between IGV opening and inlet air temperature. For the best GT performance of a given load, the IGV could be adjusted according to inlet air temperature. In addition, inlet air heating has a considerable potential for the improvement of part-load performance of GT due to the increase in compressor efficiency, combustion efficiency, and turbine efficiency as well as turbine inlet temperature, when inlet air temperature is lower than the optimal value with different IGV openings. Further, when the IGV is in a full opening state and an optimal inlet air temperature is achieved by using the inlet air heating technology, GT efficiency and SM can be obviously higher than other IGV openings. The IGV can be left unadjusted, even when the load is as low as 50%. These findings indicate that inlet air heating has a great potential to replace the IGV to regulate load because GT efficiency and SM can be remarkably improved, which is different from the traditional viewpoints.     

带可调进口导叶的多级轴流压气机非设计点性能计算

多级轴流压气机为保证非设计转速下的性能,通常采用进口导叶(IGV)以及静叶可调的扩稳方法。为获得可靠的进口导叶性能以用于压气机初步设计和扩稳方案的初步筛选,基于Banjac和Petrovic等提出的IGV损失和落后角模型与平均中径计算相结合,开发了带有IGV的多级轴流压气机性能分析工具。选用E3压气机作为算例进行计算分析,结果表明,所选用的IGV模型在较大开度内具有较好的精度和有效性。研究结果可以为多级轴流压气机初步设计和扩稳方案确定提供参考。     

Off-Design Performance of 9F Gas Turbine Based on gPROMs and BP Neural Network Model

Gas turbines are increasingly and widely used,whose research and production reflect a country’s industrial capacity and level.Due to the changeable working environment,gas turbines usually work under the condition of simultaneous changes of ambient temperature,load and fuel.However,the current researches mainly focus on the change in single condition,and do not fully consider the simultaneous change in different conditions.On the basis of single condition,this paper further studies the dual off-design performance of gas turbines under three conditions:temperature-load,fuel-load and fuel-temperature.Firstly,the whole machine model of a gas turbine is established,in which the compressor model has the greatest impact on the performance of gas turbines.Therefore,this paper obtains a more accurate compressor model by combining the engineering modeling advantages of gPROMs and the powerful mathematical calculation ability of MATLAB neural network.Then,according to the established gas turbine model,the dual off-design performance is studied,which is mainly based on the parameter of output and efficiency.The result shows that the efficiency and power output of gas turbines will decrease with the increase of ambient temperature.With the decrease of fuel calorific value,power output and efficiency will increase.As the load decreases,the efficiency of the gas turbines will decrease,and these changes are consistent with the single off-design performance.However,when the fuel and temperature change simultaneously,only adjusting the IGV angle cannot avoid the surge when the temperature is above 30°C.At this time,it is necessary to adjust the extraction rate in order to ensure the safe and stable operation of gas turbines.Therefore,the research on dual off-design performance of gas turbines has an important significance for the peak shaving operation of gas turbines.     

应用于氦气压气机的相似模化方法验证

为解决氦气压气机与空气的相似模化问题,针对进出口比容比相等的近似模化方法,采用NUMECA计算流体力学软件,以某型轴流氦气压气机级为模型,进行了数值模拟验证计算,并与试验结果做比较。从数值模拟验证可知,公式计算和数值模拟的性能曲线相差较小,氦气和空气不同工质下的气流角偏差也很小;而从空气试验结果可知,公式计算和试验结果的压比曲线基本重合,但绝热效率曲线有一定偏差。综合表明,具有常规叶型的氦气压气机,在马赫数低于0.4以及压比低于2的情况下,不考虑马赫数相等的近似模化方法是有效实用的。     

一种损失和落后角模型在轴流压气机特性预估中的应用

为了得到某型两级轴流压气机的特性曲线，采用在子午平面上叶片排间隙中设置计算站的流线曲率法对其内流场进行了数值模拟，得到子午平面上速度分布；建立了一种设计、非设计损失和落后角模型的组合，将其应用到两级压气机特性计算当中去，得到了不同转速条件下，压气机特性的变化曲线，将其同试验得到的特性线作对比，验证了损失和落后角模型在压气机特性计算当中的有效性。     

Automatic efficiency optimization of an axial compressor with adjustable inlet guide vanes

The inlet attack angle of rotor blade reasonably can be adjusted with the change of the stagger angle of inlet guide vane (IGV); so the efficiency of each condition will be affected. For the purpose to improve the efficiency, the DSP (Digital Signal Processor) controller is designed to adjust the stagger angle of IGV automatically in order to optimize the efficiency at any operating condition. The A/D signal collection includes inlet static pressure, outlet static pressure, outlet total pressure, rotor speed and torque signal, the efficiency can be calculated in the DSP, and the angle signal for the stepping motor which control the IGV will be sent out from the D/A. Experimental investigations are performed in a three-stage, low-speed axial compressor with variable inlet guide vanes. It is demonstrated that the DSP designed can well adjust the stagger angle of IGV online, the efficiency under different conditions can be optimized. This establishment of DSP online adjustment scheme may provide a practical solution for improving performance of multi-stage axial flow compressor when its operating condition is varied.     

基于平均微元级特性的压气机特性线外推方法

在燃气轮机组仿真研究中,确保压气机特性计算的准确可靠是建立燃气轮机组仿真模型的重要前提.针对现有轴流式压气机特性外推方法的不足,对压气机作出合理假设,提出了压气机平均级叶栅特性的概念,进而将压气机分解为若干串联的微元级,分段计算压气机的特性,从而使非设计工况下级进出口相似条件能够得到保证.以雷诺相似定律为基础,将每一个微元级特性外推,得到各微元级特性图,进而重构出压气机整机特性图.结果表明,新方法可以明显减小现有外推方法产生的误差,并由于平均级叶栅特性和虚拟微元级概念的引入,拓宽了压气机特性线获取的途径,提高了外推特性的可靠性.