【作者】 王春雨；

【导师】 邱朋华；

【作者基本信息】 哈尔滨工业大学 ， 动力工程（专业学位）， 2016， 硕士

【摘要】 燃气—蒸汽联合循环发电是现代发电技术发展的一种趋势,在国内的应用也越来越广泛。在实际的运行中,机组的运行会与出厂设定产生差异,例如:实际供给的燃料和设计燃料间的差异,长期工作负荷和设计负荷之间的差异等。这些差异对机组的燃烧室燃烧过程以及机组热力性能等都会产生影响,所以针对运行和设计的差异,开展燃机非设计工况、非设计燃料条件下的工作过程研究,具有重要的工程指导意义。本文是以大庆某燃机电厂一台6B容量燃机联合循环系统为研究对象,首先采用CFD计算平台,建立了针对6B燃机燃烧室的仿真计算模型,对燃用不同燃料条件下的6B燃机的燃烧室燃烧过程进行了数值模拟,对燃烧室在燃用不同燃料条件下的运行情况进行了分析,判断燃机变换燃料的可行性。然后利用GT-Pro软件建立了燃机联合循环流程热力模型,包括燃气轮机、余热锅炉、蒸汽透平等部分,并根据机组运行数据对模型进行准确性验证。最后利用建立的模型开展了两个方面的研究工作,第一、分析燃料是伴生气时,燃机电厂的负荷从50~100%变化时机组的运行特性,比较不同负荷下的机组的发电功率以及效率;第二、对采用电厂原有伴生气和非设计燃料的天然气、中热值煤气和低热值煤气的机组的热力性能进行了计算和对比。论文计算结果表明,随着燃机负荷的变化,燃气-蒸汽联合循环机组的经济性呈现整体下降的趋势,但受机组燃烧和压气机性能的影响,这种变化并不是线性的,在90%负荷下存在拐点。当燃料种类发生变化时,燃气联合循环机组的经济性也会发生变化。在不考虑其他因素的情况下,使用低热值燃料的机组经济性有增加的趋势。从燃烧室的燃烧性能看,低热值燃料的燃烧温度分布均匀性变好,稳定性增强。更多还原

【Abstract】 Electricity generation by gas-steam combined cycle is a trend for nowadays electricity produce of China,whose adoption is becoming more and more popular.In the running of the unit,the practical operating circumstance and parameters may differ from those originally designed,e.g.,the change on fuel,the change on long-term load and design load.All these changes will affect the combustion and the thermal performance of a running unit.So it is of significant guidance for engineers to study the operating performance of gas turbine under off design condition and off design fuels.In this thesis,a 6B type gas turbine combined cycle system in Daqing Gas Turbine Power Plant was used as the research model.Firstly,the CFD platform was used and a simulation model was developed for the 6B type gas turbine chamber.The combustion process of the 6B type gas turbine chamber under different fuel conditions was simulated.The operation condition of the chamber under different fuel conditions was analyzed and the possibility of changing the fuel for gas turbine was evaluated.Then,GT-Pro software was used to establish the flow model of the gas turbine combined cycle,including gas turbine,heat recovery steam generator(HRSG),and steam turbine and so on.The model was validated according to the unit operation data.At the end of the thesis,two aspects are researched.One was the operating characteristics of the unit when the load of the gas turbine power plant was changed from 50 to 100% and fuel was original associated gas.The generation power and efficiency of the unit under different load were compared.The simulation results show that the economy of the gas-steam combined cycle unit decreases with the load of the gas turbine,but it is not linear due to the combustion of the unit and the performance of the compressor.There is an inflection point at 90% load.When the fuel changes,the economy of the gas-steam combined cycle unit will also change.Without consideration of other factors,the unit economy using low heat value fuel becomes better.For the combustion performance of the chamber using low heat value fuel,the temperature distribution becomes more uniform and the stability is enhanced.更多还原