四角切圆锅炉同轴燃烧系统空气动力特性的研究

对300MW四角切圆煤粉锅炉采用低NOx同轴燃烧系统时炉内流场及燃烧器区域浓度场进行了冷态模化试验研究。分析了当二次风偏置角度、二次风与一次风动压比、燃尽风比率及燃尽风布置方式变化时，对炉内气流相对切圆直径、旋转动量流率矩、湍动度、一二次风混合、燃尽风穿透力等的影响，进而分析了对锅炉工作的影响。图7表4参6     

六角切圆锅炉燃烧器区域气固两相流场的试验研究

针对某六角切圆燃烧煤粉锅炉存在的受热面结渣问题，建立冷态试验台，采用三维粒子动态分析仪对燃烧器区域的气固两相流场进行测量，研究原始设计工况及加大上层燃烧器二次风假想切圆直径的改进工况下，燃烧器区域的气固两相速度场．试验研究表明，适当采用一、二次风同心双切圆布置形式，能有效改善炉内流场特性，从而抑制受热面结渣现象的发生．     

四角切向燃烧锅炉分隔屏过热器结构对水平烟道烟速偏差的影响

对引进型６００ＭＷ四角切向燃烧锅炉进行了冷态模化试验,首次系统地研究了屏区气流流动特性及改变分隔屏结构布置对水平烟道气流速度场偏差的影响。     

W火焰炉炉内流动特性的试验研究

为摸清从国外引进的一台330 MW W火焰锅炉炉内流动特性,依据相似模化的准则,对该锅炉建立了1∶10冷态单相试验台,在试验台上进行了变锅炉配风(即三次风占总二次风的比例R=0％、6％、14％、20％和27％共5个工况)的冷态模化试验,得出了炉内流场特征和拱部下行气流衰减规律.当R=0～6％时炉内流场基本对称,R值加大至14％后炉内流场出现偏斜现象,继续加大R值,则流场偏斜加剧,前、后墙侧下行气流的衰减特性差异变大.     

电站锅炉水冷壁高温腐蚀问题的试验研究

以大港电厂2×328.5MW机组锅炉为例,对四角切圆燃煤锅炉水冷壁高温腐蚀问题进行试验研究。在原型锅炉基础上,按1:20的比例搭建试验台。针对原炉初步设计方案,在冷态空气动力场模化试验台上,进行一次风同心反切燃烧炉内冷态试验研究。利用IFA300热膜风速仪,结合飘带观察法,对不同燃烧器布置方式下炉内空气动力场进行测量和观察,并与数值模拟结果进行对照,掌握燃烧器区域气流特性,提出解决电站锅炉水冷壁高温腐蚀问题的合理建议。     

盘山600MW机组锅炉冷态模化试验研究

对盘山６００ＭＷ机组锅炉初步设计方案,在大型冷态民动力场模化试验台上,利用先进的热速仪和烟雾,飘带示踪技术,对不同的燃烧器布置方式,锅炉炉内空气动力场进行了试验研究,掌握了燃烧器区域的内的气流旋转特性和锅炉水平烟道中气流分布特性。     

四角切向燃烧锅炉炉内冷态与热态流场特性的对比研究

通过冷态和热态实验测量研究了四角切圆燃烧锅炉的炉内流场特性。得出如下的结论：①热态的实际切圆直径相比冷态有增大的趋势；②炉内气流的旋转动量流率矩沿高度下降，热态工况旋转动量流率矩衰减速度比冷态工况慢；③一次风反切的配风方式可有效降低炉内旋转动量流率矩的水平、明显削弱炉膛出口的残余旋转和减小水平烟道入口的速度偏差。图8表3参3     

切圆燃烧反切风风量与位置对炉内流场的影响

本文采用数值分析技术对大容量切圆燃烧锅炉改变燃烧器二次风反切风量以及反切风位置时的炉内流场特性进行了全三维模拟和研究，研究结果表明在燃烧器上部二次风采用反切布置的情况下．无量纲数XJ在1左右时炉膛出口残余旋转较小，炉内气流湍动混合较好，炉内气流运动稳定；研究亦表明反切风位置对炉内流场影响较大。同时，对7个电厂13台大型锅炉进行了改造效果统计，验证了数值分析的结论。     

大型锅炉炉膛内的空气动力工况

文中给出了对ＷＧ３００ＭＷ机组锅炉炉膛进行冷态空气动力场模化试验的结果。试验结果表明，不同的二次风与一次风动压比、一次风的投运方式。燃烧器的布置方式等均会影响到炉内的空气动力场。这些结果对我国３００ＭＷ机组锅炉及其它切向燃烧锅炉炉膛的设计和运行均有重要的指导意义。     

六角切圆燃烧锅炉燃烧器区域煤粉粒径分布的试验研究

对某670t/h六角切圆燃烧煤粉炉进行冷态模化试验，应用激光多普勒测速仪（PAD）进行测量，研究燃烧器出口区域煤粉颗粒的粒径和速度分布，分析它们对受热面结渣的影响，并比较加大上层燃烧器二次风假想切圆直径后结渣状况的改善，寻求解决锅炉结渣问题的措施。     

出口结构对矩形循环流化床稀相区颗粒速度分布影响的实验研究

为了研究不同工况下出口偏置结构、挂屏的布置对稀相区颗粒速度分布的影响,在一矩形截面流化床冷态试验台上,采用高速摄影分别对稀相区左墙和前墙进行拍摄,结合粒子图像测速技术分析,获得速度分布图像。实验结果表明,分离器的偏置布置对稀相区流场的分布影响较大,受出口效应影响,左墙颗粒已不再呈现环核流动分布,中心区向后墙出口区域颗粒几乎完全为横向运动,出口下方磨损较严重。受到挂屏的阻挡和壁面摩擦,颗粒的运动方向改变,挂屏与壁面之间的区域出现了颗粒的再分布,颗粒轴向速度呈现出跟整个床截面相似的抛物线分布。挂屏的布置削弱了出口效应的影响,右墙侧颗粒的分布主要受气流和壁面摩擦的约束。     

炉膛中间截面边界条件对双切圆锅炉空气动力场计算的影响

大容量超超临界锅炉广泛采用单炉膛双切圆的空气动力组织方式,在计算流体力学软件FLUENT平台上,针对1GW超超临界单炉膛双切圆锅炉,计算了全炉膛和炉膛中间截面边界条件设为对称面和边壁条件的炉内空气动力场。计算表明,与标准κ-ε双方程模型相比雷诺应力模型(RSM)具有更高的计算精度;中间截面采用对称边界条件时,其流场分布规律与全炉膛模拟结果相似;中间截面为边壁条件时炉膛中间截面附近流速降低,但对整个炉膛流场影响较小;中间截面采用这两种边界条件均会导致1#、6#角射流衰减缓慢而冲刷炉膛前墙中间水冷壁。     

超超临界锅炉炉内燃烧过程的数值模拟

采用计算流体力学软件PHOENICS，选择合理的数学模型，对1台1000 MW超超临界单炉膛双切圆煤粉炉内的燃烧过程进行数值模拟．着重研究了单炉膛双切圆燃烧特性、炉内焦炭燃烧特性及NO生成特性。结果表明：燃烧器前后墙布置导致炉内气流呈椭圆形，NO生成总体水平较低，焦炭燃尽效果较好，但在炉膛高度方向40m以上的区域，烟气高温区及大量未燃尽焦炭偏向前墙附近，且未燃尽焦炭在辐射屏区逐渐燃尽。针对这一问题提出了解决方案，结果表明：改进后的工况明显提高了焦炭的燃烧速度．使其在屏区以下基本燃尽，NO2排放量也有所降低。     

台车式退火炉流场分析及设计研究

通过研究台车式退火炉的烟气流动情况，提出了影响烟气流动的关键因素是烧嘴和排烟口的位置，烟气在炉内的速度大小及分布对炉子的加热效率和钢锭的退火质量有重要意义。在此基础上，设计了一种新型的退火炉型，流场计算表明，该炉型具有省能、热效率高并能提高钢锭退火质量等优点。     

切向炉内多组小屏尾部分离涡的研究

利用IFA300恒温式热线风速仪，首次使用三维可移坐标架给六线涡量探针定位，并用伺服电机驱动其固定座，采用条件采样技术测量了引进型切向燃烧煤粉炉内多组小屏尾部的涡量场。将多组小屏比拟为薄板机翼，研究了由于上升气流螺旋形流动和烧流过薄板翼的复合结果，在多组小屏尾部形成的分离涡，确定了分离涡的大小。研究发现：分隔屏（前屏）区尾部，炉膛右半部分有明显的分离涡，并且有些分离涡伴有方向相反的另一涡出现。速度场和涡量场的测量结果表明：右侧墙附近，不仅流速高，而且涡度大，为研究炉内煤粉燃烧及NOx的污染控制技术提供了理论依据。     

Asymmetric combustion characteristics and NOx emissions of a down-fired 300 MWe utility boiler at different boiler loads

To investigate the aerodynamic field, cold airflow experiments were conducted under different boiler loads in a cold small-scale model of a down-fired pulverized-coal 300 MW_e utility boiler. At 300 MW_e and 250 MW_e loads, a deflected flow field appeared in the lower furnace. In contrast, at a 150 MW_e load, a U-shaped flow field appeared in regions near the left- and right-side walls in the lower furnace. Concurrently, the regions near the two wing walls adjacent to the front arch had received deflected upward airflow emanating from the region near the rear wall. Moreover, a symmetric W-shaped flow field appeared in the central regions below the front and rear arches.Industrial-sized experiments on the full-scale furnace were also performed at different loads with measurements taken of gas temperatures in the burner region and near the right-side wall, as well as heat fluxes and gas components in the near-wall region. Asymmetric combustion appeared at 300 MW_e and 250 MW_e loads, with large differences arising in gas temperatures, gas components, and heat fluxes between zones near the front and rear walls. At 150 MW_e load, gas temperatures, gas components and heat fluxes are, in general, symmetrically distributed throughout the furnace. By decreasing the load, differences in gas temperatures, gas components, and heat fluxes near the front and rear walls decrease, as did NO_x emissions. Meanwhile, the carbon content in fly ash essentially decreased, yielding an increase in boiler efficiency assisted by a drop in exhaust gas temperature.     

W型火焰锅炉冷态空气动力特性的测试研究

针对引进的配备直接缝隙式燃烧器的法国Ｓtein公司３６０ＭＷ的Ｗ型火焰锅炉进行了冷态模型的空气动力特性研究。利用热线风速仪测量炉内的流场速度，得出了不同工况下炉内Ｗ型气流的流场图，并对不同工况流场的气流速度分布规律、炉内气流的充满度、气流行程、炉膛出口处的速度偏差等进行了分析，研究了炉内空气动力场的特性和变化规律，测试了Ｗ型火焰锅炉火焰短路与炉膛出口速度偏差的性能。     

Numerical study of the effect of imaginary circle diameter and initial flow field on the aerodynamic field in a tangentially fired furnace

In this paper,the effect of the imaginary circle diameter φi and the initial flow field on the aerodynamic field in a tangentially fired furnace was studied by numerical simulation and experments in the cold model.Results show that merely reducing the imaginary circle diameter φi can not significantly reduce the rotational diameter φ in the range considered.The flow still rotates counter-clockwise stably and does not change rotation direction when the direction of all jet axes are deflected suddenly to the opposite rotation direction by up to 5.4° in a counter-clockwise flow filed.It is the first time that the numerical simulation results were obtained which agreed quite well with this experimental phenomena qualitatively.The experimental data,ie.e,the rotational diameter φ and the maximum velocity on the symmetric central line of furnace Vm,are only a bit larger than the simulation resuts.It is shown that the initial flow field has an important influence on the aerodynamic field in the funace.Other measures have to be taken as well in order to reduce φ to resist slagging and high temperature corrosion of furnace tubes.Moreover,a new kind of grid arrangement was proposed in this paper,which can reduce effectively the false diffusion at the exit zone of burner.     

An experimental investigation for cold-state flow field of regenerative heating annular furnace

According to modeling theory, a cold-state model with 1:10 scale was established for a regenerative heating annular furnace. Following to the PIV (Particle Image Velocimetry) testing method by using tracing particles, a high-speed camera was adopted to measure the velocity distribution in the furnace. The experimental results found that the airflow from the burners could not be sucked by the first opposite burner on the other side wall; and that closing the soaking section results to farther suction location, which prolongs gas residence time in the furnace, and it also avoids the rich-fueled smoke gas short circuit which usually occurs in the regenerative heating furnace. The velocity profiles have a great variance in the chamber. With farther location to the nozzle, velocity profiles are more even. At a certain angle of the air jet, there are two vortexes close to the burner. With higher flow rate, it is easier for the airflow to reach the opposite chamber wall.