Performance measurement of a smoke extraction system for buildings in full-scale hot smoke test

The current inspection method for a smoke extraction system in Taiwan measures whether the air flow of the smoke vent conforms to the design value. However, this method is inapplicable to natural smoke extraction systems. As the plugholing effect is disregarded, adequate air flow cannot ensure that the system will exhaust smoke effectively during a fire. Hence, a full-scale hot smoke test for smoke extraction systems is necessary. Some international test criteria are formulated using visible smoke and alcoholic fuel which is pollution-free after combustion. The effectiveness is judged only by visually observing the smoke’s flow direction, which is indeed unscientific. This study used a string of vertical smoke layer measuring instruments composed of several approved photoelectric smoke detectors, as well as a light attenuation measuring device composed of illuminance meters to conduct tests on the effect of makeup air. The results proved that the former one uses different height induction times to judge the position of the smoke layer effectively, while the latter one uses the light attenuation rate to distinguish the smoke density instantly and accurately. The obtained experimental data were consistent with the onsite smoke distribution. The two sets of equipment designed in this study can be used for full-scale hot smoke tests to obtain performance data for a smoke extraction system.     

实验室条件下航空发动机冒烟问题研究

根据航空技术的发展趋势,航空燃气轮机高推比的要求愈加迫切,因此,要求燃烧室具有很高的工作压力和温度,与此同时,发动机碳化合物排放因其危害的问题特别突出。发动机冒烟一方面是引起环境恶化的重要因素,另外对于军用飞机来讲,发动机冒烟会使飞机隐蔽性受到极大威胁,因此,深入研究发动机冒烟问题成为目前迫切解决的重要课题。目前,世界上对航空发动机冒烟的问题进行了广泛的关注,冒烟问题已经成为航空发动机低污染燃烧技术首先要解决的重点课题之一。本文主要叙述了烟的测量和冒烟问题基本试验规律,并讨论烟浓度的测量方法以及引起冒烟的机理。     

Indoor measurement method of smoke screen disturbance efficiency based on Gaussian diffusion model

Because of ground clutter wave interf e rence,it is difficult to measure smoke screen disturbance in the field.In this pape r,a kind of indoor measurement method of smoke screen disturbance efficiency ba sed on Gaussian diffusion model is put forward.As a characteristic,the measur ement result of smoke screen area density proves that the indoor measurement met hod of smoke screen disturbance efficiency based on Gaussian diffusion model is fea sible.     

基于二进小波和抗噪形态学的烟雾边缘检测算法

针对枪口烟雾图像的不规则性以及烟雾扩散速度快等特点,传统的边缘检测算法无法高效地提取烟雾边缘轮廓的问题,对烟雾图像采集技术、烟雾图像预处理技术以及烟雾图像边缘检测技术进行了研究,提出了一种改进的二进小波和抗噪形态学融合的边缘检测算法.首先,在 B 样条二进小波基础上,将二进小波消失矩的阶数提高到四阶;其次,选取方向不同的结构元素,得出改进的形态学算子;最后,用小波逆变换重新构造枪口烟雾图像,对其进行锐化处理,输出边缘信息.仿真结果表明,该算法检测出来的枪口烟雾图像边缘定位准确且清晰完整,能有效抑制噪声,在客观方面优于传统的边缘检测算法.     

多信息识别技术在矿井烟雾监测中的应用研究

煤矿火灾早期烟雾监测是矿井火灾早期预警的重要手段。针对采用离子型、光电型、气敏型单一检测原理的矿用烟雾传感器易出现误报警问题,该文提出充分提取矿井烟雾的特征信息,采用多信息识别技术,结合自适应数据融合和逻辑判断方法,实现矿井烟雾智能检测识别。通过实际测试验证,基于多信息识别技术的矿井烟雾检测方法,能有效抑制煤矿环境中的典型干扰因素,识别准确率达到100%。     

一种抽油烟机的优化研究

针对传统抽油炯机不易清洗、噪音偏大,寿命偏低、能耗较高等问题,将科恩达效应空气倍增器技术、喷气式飞机引擎及汽车涡轮增压技术应用到抽油炯机系统中。开展了抽油炯机抽烟系统、油烟处理系统、电控系统分析与设计,实现了对系统的优化。建立了压力损失与结构设计之间的关系,从结构设计角度对炯道系统环形导气腔、烟道的3种设计方案进行了评价,提出了抽油烟机抽烟系统优化的算法和数据分析;从智能化控制角度设计了硬件电路,设计集成了自动光感应、油烟检测感应、自动控制功能,检测部份包括键盘输入、烟雾、煤气检测,控制部份包括AT89C51单片机、开关电路、报警与定时显示、照明。最后进行了工况试验。研究结果表明：优化后的抽油烟机系统能耗降为传统抽油烟机的71．8％,全压效率约为27％,噪音≤65dB。     

新型消光式烟度计的设计

根据消光式烟度计的工作原理,设计了一种基于光电检测技术的新型消光式烟度计.当光束通过机动车排出的尾气时,会产生对光的吸收和散射,从而减小光能量.将衰减前后的光能量相比较,通过计算机处理,可得到尾气的消光度与烟度值.讨论了仪器设计的技术指标、结构、定标及特点.检测试验证明,仪器性能稳定,测量数据重复性好.     

A two-dimension velocity field measurement method for the thermal smoke basing on the optical flow technology

The confine and heat are remarkable features in building fire research, as well as is a barrier for flow velocity profiles measurement, which the general method is unsuitable for this experimental environment. Therefore, this paper develops a measurement method for the acquisition of the thermal smoke flow velocity profiles in the fire building experiment. Firstly, we utilize the smoke itself particle distribution to replace the manual track particles in which reduce the complexity of the measurement method for fire experiments system. Secondly, we optimize the non-uniform distribution of smoke soot particle and utility the smoke stratification characteristics basing on the optical flow technology. The four optimized methods were compared to acquire reasonable smoke velocity distributions. Finally, we take advantage of filter post-process method to smooth the smoke velocity profiles in the main transportation direction. Moreover, a series of experiments and simulations show the feasibility of this image-based method in which the pre-process, optical calculation and smooth methods were established to denote reasonably the smoke flow velocity gradient and inclined upward trend nearby the corridor open. Meanwhile, it is not only in acquiring two-dimension smoke field velocity, while also can fulfill the other particle flow movement.     

车窗开闭状态对双层列车车厢内火灾烟气特性的影响

车窗开闭状态对列车火灾影响较大,而在现有研究中,对双层列车火灾烟气特性研究较少。基于计算流体动力学理论(Computational dynamics theory, CFD),建立双层列车单节车厢的火灾数值计算模型,采用大涡模拟方法(Large eddy simulation,LES)对车内流场进行数值模拟。在火源位置、火源功率以及列车运行速度等参数不变的条件下,研究不同位置车窗的开闭状态对双层列车上下两层车厢内烟气特性的影响。结果表明,打开不同位置的车窗对车厢内烟气特性影响较大;打开火源前方的车窗使双层列车整节车厢的烟气层高度升高、CO浓度降低、烟气温度下降,车厢内烟气向有利于乘客逃生的方向发展;打开火源后方的车窗只降低车厢后部区域CO浓度和烟气温度,烟气层高度升高。根据研究结果,为双层列车逃生疏散设计提供参考。     

三重四极杆气质联用法测定卷烟主流烟气中NNK

为了测定卷烟主流烟气中4-(甲基亚硝胺基)-1-(3-吡啶基)-1-丁酮（NNK）的含量,建立了三重四极杆气质联用仪（GC-MS/MS）测定方法。按照标准条件抽吸卷烟,捕集在剑桥滤片上的卷烟烟气粒相物用二氯甲烷萃取并以氘代NNK为内标,经固相萃取净化后,用三重四极杆气质联用仪测定卷烟烟气中NNK的含量。方法的相对标准偏差为2.3%～2.7%（n=6）、回收率为98.9%～116.8%、定量下限为0.087 ng/cig,完全可以满足日常检测的要求。本方法采用商品化固相萃取柱,避免了样品浓缩、转移等操作步骤,节省试剂并且提高了工作效率。应用本方法对2R4F和其他不同类型的卷烟样品烟气中NNK进行了检测,检测数据与国家标准方法GB/T 23228 2008（GC-TEA）一致性好,验证了本方法的准确性。     

全新吸油烟机气动布局研究

油烟机的气动布局是决定整机吸油烟效果的关键因素,通过对两种气动布局对比,得出风机卧式布置有利于负压外扩,减少流动损失,更适合中式厨房。创新的使用了水滴气动外形的导流罩,很好的与离心风机卧式布置方案匹配。为了减少流动分离,对三种蜗壳出口方案对比,优选最佳方案;并进行蜗壳小型化设计来满足橱柜设计标准,最大限度地利用集烟空间,使油烟流经过程中所受的阻力最小,以提高排油烟能力。     

气溶胶浓度对偏振光传输特性的影响

采用双光路检测配置条件,结合Mie氏理论,运用斯托克斯矢量形式,以烟雾模拟特定气溶胶环境,探究偏振光经过不同烟雾环境的传输变化情况。考虑到大气气溶胶成分、质量浓度和颗粒大小以及光源的波长和偏振态等多因素的影响,主要在气溶胶质量浓度和光源配置方面进行研究。实验结果表明,不同烟雾质量浓度时,水平线偏振光的偏振特性基本不改变,右旋偏振光和45°线偏振光退偏程度随烟雾质量浓度的增加而增加,460nm和556nm波长的偏振光在变化趋势上保持一致。     

烟气分析仪在线监测工业锅炉运行状况

使用烟气分析仪对燃煤锅炉实际运行工况进行了在线监测。利用监测数据比较了锅炉系统技术改造前后的运行状况。结果表明,技术改造取得了令人满意的效果。烟气温度、烟尘和SO2排放浓度降低,锅炉用煤量减少,污染排放达到国家标准,锅炉整体运行效率提高。     

光电离质谱技术快速采样研究自然抽吸卷烟烟气的口腔残留

建立了一套烟气抽吸采样系统,结合光电离飞行时间质谱,实时、在线分析不同抽吸者在自然抽吸卷烟过程中卷烟烟气气相化学成分的口腔残留。利用毛细管负压对吸烟者吸入和呼出口腔的烟气气相成分取样,直接引入至光电离质谱腔中进行电离、分析。对5种烤烟型卷烟样品中选取的醛酮类、苯酚、甲硫醇、氮杂环类以及不饱和碳氢化合物等14种化学成分进行不同抽吸者口腔残留测试。结果表明,烟气在口腔中停留2 s时,3种类型抽吸习惯（浅度烟龄、中度烟龄和重度烟龄）的7名人员口腔中残留效率大致分为3类,醛酮类属于口腔高残留化合物,苯酚、甲硫醇和氮杂环类属于中等残留化合物,而不饱和碳氢化合物属于相对较低残留化合物。这种直接从吸烟者抽吸过程取样分析的方式,能够真实反映吸烟者在自然抽吸过程口腔中烟气的残留情况。     

通风机组合对过海地铁区间隧道通风能力影响的试验研究

基于工程现场参数,搭建了某过海地铁区间隧道物理模型.在该模型及其通风排烟系统上,针对双压和双压一抽的两种通风机组合,分别测得了通风机变频频率值及其电功消耗,同时,测得了排烟道与行车道的风速,以及行车道静压值.通过实测数据,发现左右双侧行车道静压均呈对称分布,其镜像面为吊顶排烟口,且与通风机组合无关.在双压的通风机组合下...     

An experimental study for the flow rates of automatic pressure smoke dampers and their applications

Smoke spread from a fire is a major cause of mass casualties. To suppress smoke spread, escape routes are pressurized and smoke dampers are used. In Korea, the automatic pressure smoke damper (APSD) was recently adopted in escape routes, and the number of APSDs is increasing concomitantly with the increase in the number of high-rise buildings. In this study, a more efficient method for the assessment of the flow rates of APSD was experimentally studied for multi-blade types of which the blade angle is controlled. A modified wind tunnel was used to measure the relationship between the pressure difference and the flow rate with a blade angle variation for three kinds of APSD. As a result, the performance of the APSDs could be presented as a function of the pressure difference and blade angle. Using this performance function, a volume of information regarding the characteristics of the APSDs could be easily extracted. Furthermore, some experimental methods, based on the performance of the APSD, were suggested to assess the smoke suppression velocity and the effective leakage area in practical buildings.     

Deposition of lead and cadmium released by cigarette smoke in dental structures and resin composite

Cigarette smoke is a significant source of cadmium, lead, and toxic elements, which are absorbed into the human organism. In this context, the aim of this study was to investigate in vitro the presence of toxic elements, cadmium, and lead deriving from cigarette smoke in the resin composite, dentine, and dental enamel. Eight cylindrical specimens were fabricated from resin composite, bovine enamel, and root dentin fragments that were wet ground and polished with abrasive paper to obtain sections with 6‐mm diameter and 2‐mm thickness. All specimens were exposed to the smoke of 10 cigarettes/day during 8 days. After the simulation of the cigarette smoke, the specimens were examined with scanning electron microscopy (SEM) and the energy‐dispersive X‐ray analysis. In the photomicrographic analysis in SEM, no morphological alterations were found; however, the microanalysis identified the presence of cadmium, arsenic, and lead in the different specimens. These findings suggest that the deposition of these elements derived from cigarette smoke could be favored by dental structures and resin composite. Microsc. Res. Tech., 2010. © 2010 Wiley‐Liss, Inc.     

Relation between particulate emissions and exhaust smoke level in premixed charge compression ignition engine

For simplicity in measurement, the smoke level or opacity of the exhaust gas is often measured in diesel engine tests for the purpose of estimating the level of particulate emissions in the belief that smoke level is proportional to the particulate emissions. Existence of the correlation between these two has been well established in conventional diesel engines, but it is not clear yet whether the linear relationship stays in PCCI engines, which are known to emit significantly less NOx but more hydrocarbons than the conventional diesel engines. The objective of this study was to investigate the existence of the correlation between the smoke level and particulate mass in a directly fuel-injected PCCI engine with a DOC in the exhaust system. The smoke and PM are simultaneously measured before and after the DOC, while the single-cylinder diesel engine is operated in either diesel or PCCI combustion mode under various operation conditions. The study reveals that many more hydrocarbons and particulates are emitted in PCCI combustion than in the diesel combustion, and the strong correlation between the engine-out smoke level and particulate emissions in the diesel combustion does not exist in PCCI combustion. The correlation, however, comes back in the post-DOC measurements where most of SOF contained in PM is removed by the DOC.     

油田热采锅炉燃烧监测控制系统的研制与应用

辽河油田稠油资源非常丰富，目前稠油开采的主要方法是向地层加压注蒸汽的热采方法。因此燃气、燃油注汽锅炉的排烟热损失是影响热效率和采油成本的主要因素。在不同负荷的工况下，控制合适的过剩空气系数，把排烟热损失调整到该工况下的最小值，使锅炉的热效率达到最高。本锅炉燃烧监测控制仪就是通过监测烟气温度和氧含量，经过仪器专家系统分析计算，显示过剩空气系数和排烟热损失，作为操作人员调节燃料空气配比的依据，或与自动控制装置连接，实现进风自动控制，达到充分燃烧，起到降低燃料消耗，减少环境污染目的。该系统运行后，具有显著的经济效益和社会效益。     

80万吨重油催化装置能量回收三机组扩能设计

介绍了80万吨重油催化装置能量回收三机组扩能设计及节能效果。三机组是烟气轮机、轴流风机和电动机组。为了确保重油催化装置扩能后能耗匹配,对三机组进行了扩能设计。轴流机在三机组里与烟气轮机同轴,其安全性及可靠性直接影响烟气轮机的运行。依据烟气轮机的最大负荷,确定了烟气轮机的设计方案;按照烟气轮机的最大轴功率,确定了轴流风机的扩能方案,并对其配套系统进行了优化设计,实现了预期的节能目的。