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1.
旋流燃烧器的稳燃及其结构优化分析   总被引:2,自引:0,他引:2  
简要叙述了国内常见几种旋流燃烧器的稳燃措施,从燃烧器流场和煤粉颗粒运动轨迹的角度分析了对低挥发份煤燃烧稳定性的影响。介绍了新近研究的花瓣稳燃器及其流场特点。指出该稳燃器在加速煤粉气流与高温回流烟气之间的混合时,避免煤粉气流过早向二次风扩散,引导煤粉颗粒进入回流区,有利于燃用低挥发份煤和低负荷稳燃及降低NOx排放等。另外,还介绍了ABT公司最近推出的“弓形”低NOx燃烧器;最后,提出了旋流燃烧器,并提出了旋流燃烧器结构优化的建议。  相似文献   

2.
稳燃腔煤粉燃烧器对煤粉燃烧稳定和强化的研究   总被引:6,自引:1,他引:5       下载免费PDF全文
从煤粉燃烧的稳定与强化的理论和试验两方面,分析了稳燃腔燃器对煤粉燃烧所起的稳定和强化作用,并介绍了稳燃腔燃烧器实验室研究结果和工业应用结果。  相似文献   

3.
该文对稳燃腔煤粉燃烧器中粒子尺寸的动态分布进行了测量,讨论了该燃烧器的稳燃机理,并介绍了这种燃烧器在410t/h锅炉上的稳燃,调峰应用研究结果。  相似文献   

4.
稳燃腔煤粉燃烧器对不同煤种燃烧稳定性的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
本文利用三维粒子动态分析仪测量了稳燃腔煤粉燃烧器回流区的流场,并比较了钝体不同位置的回流区特征。实践说明通过调整钝体的位置及改变稳腔煤燃烧器的某些结构尺寸,可以极大的改善不同煤种的燃烧稳定性。  相似文献   

5.
旋流燃烧器的稳燃性能分析   总被引:6,自引:2,他引:6  
赵伶玲  周强泰 《动力工程》2005,25(3):364-368,386
针对旋流燃烧器燃烧低挥发份煤的稳燃问题,介绍了扩口、扩锥、浓淡燃烧、齿环稳燃器等国内外的稳燃措施,采用数值方法模拟了旋流燃烧器一次风流场,详细分析了旋流燃烧器的流场特性。分析得出,扩口、扩锥、浓淡燃烧等稳燃措施没有考虑煤粉气流进入炉膛与高温烟气的迅速混合问题。在这些稳燃措施的流场中,煤粉气流进入炉膛,除脉动外,首先沿回流区外缘流动,向外扩张,而不是迅速与热烟气混合,因此,对于低挥发份煤不能起到良好的稳燃作用。提出了解决旋流燃烧稳燃问题的新的研究方向,拓展了稳燃理论,介绍了花瓣形稳燃器,为旋流燃烧稳燃技术的发展提供了新思路。图8参9  相似文献   

6.
本文主要研究直流燃烧器与旋流燃烧器的一次风煤粉的稳燃技术(包括烟气回流与煤粉浓淡偏差技术),论述它们对炉内燃烧与NOx生成的作用,证明它们是稳燃低NOx燃烧器。  相似文献   

7.
详细地介绍煤粉射流在炉膛内着火的机理,全面地分析了对流换热和辐射换热对不同粒径煤粉颗粒的加热作用,对传统的煤粉着火作了评论和分析,同时分析了其它影响火焰稳定的因素。分析了直流煤粉燃烧器和旋流燃烧器稳燃机理,着重指出了这两类燃烧器各自的优缺点。在综合了直流和旋流煤粉燃烧器优点的基础上,提出了一种多功能、可调节、自适应外旋流、内直流煤粉主燃烧器,初步讨论了其应用的可能性。  相似文献   

8.
秦鹏  刘先斐等 《东方锅炉》2001,(1):15-17,34
本文针对劣质煤种稳燃问题,从稳燃燃烧器和一、二次风配比试验方面提出了稳定煤粉燃烧的措施,并以安阳电厂9^#锅炉燃烧调整试验为例介绍了以上理论与实践的应用结果。  相似文献   

9.
稳燃腔煤粉燃烧器的试验研究及应用   总被引:7,自引:0,他引:7  
陈刚  丘纪华 《动力工程》1994,14(6):37-41
为了提高劣质煤燃烧稳定性,利用三维LDA测量了稳燃腔燃烧器回流区三维速度分布及湍流度分布,在单火嘴试验台上进行了燃烧试验,并在220t/h燃用劣质无烟煤锅炉上投入实际应用。燃烧试验和实际应用结果都表明,稳燃腔燃烧器对提高劣质煤燃烧稳定性具有很好效果。  相似文献   

10.
浓淡旋流煤粉燃烧器低负荷稳燃性能试验研究   总被引:1,自引:0,他引:1  
针对霍州电厂发电机组频繁参与调峰的实际情况 ,研制开发了浓淡旋流煤粉燃烧器 ,并在该电厂锅炉上进行了低负荷稳燃性能试验 ,试验结果表明该燃烧器具有较强的低负荷稳燃性能。  相似文献   

11.
Swirling flows have been commonly used for a number of years for the stabilization of high-intensity combustion processes. In general these swirling flows are poorly understood because of their compelexity. This paper describes the recent progress in understanding and using these swirling flows. The main effects of swirl are to improve flame stability as a result of the formation of toroidal recirculation zones and to reduce combustion lengths by producing high rates of entrainment of the ambient fluid and fast mixing, particularly near to the boundaries of recirculation zones. Two main types of swirl combustor can be identified as follows:The Swirl Burner. Here swirling flow exhausts into a furnace or cavity combustion occurs in and just outside the burner exit.The Cyclone Combustion Chamber. Here air is injected tangentially into a large, usually, cylindrical chamber and exhausts through a centrally located exit hole in one end. Combustion mostly occurs inside the cyclone chamber.Initially the isothermal performance of swirl combustors is considered, and it is demonstrated that, contrary to many previous assumptions, the flow is often not axisymmetric but three-dimensional time-dependent. Under most normal nonpremixed combustion conditions, the swirling flow returns to axisymmetry, although there is still a residual presence of the three-dimensionality, particularly on the boundary of the reverse flow zone. Swirl increases considerably the stability limits of most flames; in fact with certain swirl burners, the blow-off limits are virtually infinite. Cyclone combustion chambers have large internal reverse flow zones which provide very long residence times for the fuel/air mixture. They are typically used for the combustion of difficult materials such as poor quality coal or vegetable refuse. In contrast to the swirl burner which usually has one central toroidal, recirculation zone, the cyclone combustor often has up to three concentric toroidal recirculation zones. Sufficient information is also available to indicate that stratified or staged fuel or air entry may be used to minimize noise, hydrocarbon, and NOx emissions from swirl combustors.  相似文献   

12.
用三维流动数值计算模型,对一台130吨/小时锅炉有用双通道浓淡煤粉燃烧器的单只燃烧器喷口流场计算和冷态实验结果比较证明了该燃烧器能够形成回流区,且调节腰部风可以改变回流区的长度。该燃烧器具有高效,低负荷稳燃、火焰可调,低NOx排放性能。  相似文献   

13.
This paper presents a new burner design for lean premixed stratified combustion for experiments to validate models for numerical simulations. The burner demonstrates combustion phenomena relevant to technological applications, where flames are often turbulent, lean premixed, and stratified. The generic burner was designed for high Reynolds number flows and can stabilize a variety of different lean premixed flames. The burner’s design and its versatile operational conditions are introduced. Shear, stratification, and fuel type are parametrically varied to provide a sound database of related flow configurations. Reacting and corresponding non-reacting configurations are examined. Experimental setups and the results of laser Doppler velocimetry (LDV) and particle image velocimetry (PIV) are presented and discussed. LDV measurements provide radial profiles of mean axial velocity, mean radial velocity, and turbulent kinetic energy as well as integral time scales. High-speed PIV is introduced as a novel technique to determine integral time and length scales and provide 2D 2-component velocity fields and related quantities, such as vorticity.  相似文献   

14.
刘伟  陈琪 《工业加热》2011,40(5):24-27
为探索适用于煤掺烧生物质的旋流燃烧器结构形式,采用Fluent软件对旋流燃烧器进行了冷态数值模拟,计算结果表明旋流叶片安装角度合适,旋流燃烧器中流出的气体质点既有旋转向前的趋势,又有从切向飞出的趋势,气流初期扰动非常强烈。研究发现改变燃烧室形状对燃烧室内气相速度场、颗粒轨迹以及湍流强度等特性参数都有较大影响,长方体型燃烧室对燃料和氧化剂的混合和燃烧更有利。  相似文献   

15.
In this paper the results of experimental and numerical investigations of swirl burner were presented. Mathematical model for prediction of velocity, temperature and concentration fields of axisymmetrical confined swirl turbulent flame was developed. Model consists of few mutually coupled segments related to basic processes in turbulent flows with combustion. The original combustion rate model based on the ideal reacting hypothesis within fine structure of turbulence was applied. The comparison of the experimental results with computation showed satisfactorily agreement between the model and the experiment. This analysis also showed the importance of the proposed combustion rate model with simultaneous influence of both chemical kinetics and turbulent effects.  相似文献   

16.
低热值煤层气燃烧器的数值模拟   总被引:3,自引:0,他引:3       下载免费PDF全文
对一种低热值煤层气燃烧器进行了全尺寸的三维燃烧数值模拟研究,预测了燃烧器出口的流场、温度和组分分布情况,并考察了不同热负荷和不同喷口形式对燃烧器性能的影响。结果表明该燃烧器具有较宽的负荷调节能力,渐缩喷口燃烧器燃烧温度最高且射流刚性好,50%~100%热负荷内渐扩喷口燃烧器燃烧性能最佳,25%热负荷下渐缩喷口燃烧器燃烧性能最佳。模拟结果对该燃烧器的进一步优化设计有一定的指导意义。  相似文献   

17.
介绍了对一台容量为50WM锅炉的煤粉燃烧器的改造过程。根据燃烧理论,将原来的煤粉燃烧器改造成了微油点火燃烧器,并介绍了燃烧器的设计思想,以及小油枪的计算方法。微油点火燃烧器采用了分级燃烧方式和二次风冷却技术,能够很好起到稳燃和冷却的作用。改造后的效果表明该燃烧器锅炉启停速度快,燃烧稳定,节约燃油,降低了生产成本。  相似文献   

18.
介绍了对广西合山电厂6号锅炉进行燃烧器改造的情况.通过采用将水平浓淡稳燃腔煤粉燃烧器和多功能燃烧器相结合的技术,使整个燃烧器区域的燃烧稳定性提高,锅炉效率提高了6.6%,为其他电厂类似问题提供了借鉴和经验.  相似文献   

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