【作者】 张建华；

【导师】 钟英杰；

【作者基本信息】 浙江工业大学 ， 热能工程， 2013， 硕士

【摘要】 近20年来,粒子图像测速(Particle Image Velocimetry,PIV)技术的发展逐步成熟,是非常有前景的全场测速技术。目前国内对PIV的应用研究主要局限于无反应流的流场,对于反应流研究较少,而且主要侧重于稳态燃烧,而脉动燃烧／燃烧振荡等周期性或者非周期性变化流场PIV技术鲜见应用。脉动燃烧技术因其燃烧强度高和污染物排放低等优点受到国内外的关注,成为燃烧科学和技术研究中的热点之一。基于以上两点,本文对PIV技术应用于脉动火焰流场展开研究,主要工作和成果如下：1.对示踪粒子的跟随性和散射性展开了探讨,建立了脉动火焰流场中示踪粒子跟随性数学模型,利用Matlab数值计算得到了空气流场中常用示踪粒子各个粒径下的跟随性,定量分析了粒径对跟随性的影响,并且对粒子散射性做了分析,完成了脉动火焰流场中示踪粒子的选型；2.利用流化床原理,设计了示踪粒子发生装置,对此进行了预备实验,成功均匀产生粒子,并且浓度满足测量的要求,将该装置应用于脉动试验台,搭建了脉动火焰流场PIV测试系统,得到了较好的效果；3.计算了PIV系统两束激光脉冲时间间隔△t,通过对PIV系统各个参数和数据处理方法的正确选择,提高了测试精度,成功得到了冷态和热态各个工况下的流场矢量图和流线图。实验发现,燃烧反应情况下,速度变化幅度比冷态情况下要大,且在声场作用下更明显。4.通过热线风速仪测得管内流速和燃烧器出口射流速度的转化关系,通过实际速度的计算,验证了PIV系统测得的流场矢量大小的正确性。对脉动火焰流场进行了大涡模拟,得到了涡的生成发展过程,其结果与PIV所测涡的运动规律一致。更多还原

【Abstract】 In the past20years,Particle Image Velocimetry(PIV) technology has been far riper, with the development of accuracy and rapidity, It had been a very promising overall velocimetry. However, current application of PIV mainly limited to the non-reacting flow field, but less on the reaction flow study, and most PIV studies focused primarily on steady combustion flow field,but other cyclical or non-cyclical Unsteady flow field like pulse combustion or combustion oscillation has no application of PIV technology.Pulse combustion technology become one of the hot spots on combustion science and technology because of its efficient combustion and low emission.The study on the pluse combustion is not comprehensive enough,so it is important to study it extensively and in-depth.In this paper,the application of PIV technology on the pluse combustion was studied.The main work and achievements are as follows:1.The following features and scattering property of tracer particle was investigated.A mathematical models of the tracer’s following features in the pluse flame was built and the effect of particle diameter on the following features was analyzed quantitatively by the Matlab numerical calculation.And the scattering property was analyzed too.The selection of tracer particle in the pluse flame was completed.2. A tracer particle generating device was designed by using the fluidized bed principle. Particles can be uniformly generated,and the concentration meet the requirements of measurement through the preparation experiments.Then the device was applicated to the Rijke pluse combustor with the PIV technology,the satisfactory result was obtained.3.The time between two pluses of PIV system was calculated,and the accuracy was developed through the improvment of the parameters and the right choice of data processing.The vector diagram and streamline chart of cold flow and combustion flow were obtained.The data shows that the reacting fluctuating velocities are larger than non-reacting fluctuating,this phenonmenon was more obvious under the acoustic excitation.4.The transforming relationship between the tube flow velocity and buner jet velocity was measured by hotwire anemometer(HWA),the vectors measured by PIV were verified to be correct by comparing it with the calculation results.The large eddy simulation(LES) was used to study the pluse flame,the formation and development of vortex was obtained,and its motion was same with the result measured by PIV technology.更多还原