摘要
通过对空气和煤粉的两相流理论的研究,分析了乏气送粉锅炉风粉混合过程的基本特征,从工程应用角度提出若干基本假设,提出了中储式制粉系统通用的动能法煤粉浓度测量方法。通过对大量采集数据的统计分析,利用机理与回归相结合的方法,得出算法模型,并实时应用于风粉在线监测系统,简化了对问题的描述,并保证了所建立的风粉混合过程数学模型得以简化,为后续的煤粉浓度测量的研究工作打下了扎实的理论基础。结果表明,风粉混合后动压与混合前一次风(乏气)动压之间的比值能够代表管道内煤粉浓度的大小。此方法适用于中储式制粉系统的煤粉浓度测量。
Through a study of air and pulverized coal two-phase flow theory,analyzed were the basic characteristics of an air and pulverized coal mixing process in a pulverized-coal boiler,featuring the transport of pulverized coal by exhaust gas.From the standpoint of engineering applications,several basic assumptions were proposed.A method based on kinetic-energy for measuring pulverized coal concentration was put forward,which has been commonly used in a bin and feeder system.Through a statistical analysis of numerous acquired data and by using a method combining relevant mechanism with regression,a calculation model was obtained and used on a real-time basis in an on-line air and pulverized coal monitoring system,thus simplifying the related problem description,and guaranteeing the simplification of the mathematical model established for air and pulverized coal mixing processes.The forgoing has laid a solid theoretical basis for subsequent research on the measurement of pulverized coal concentration.It has been found that the ratio of the kinetic pressure between two cases,namely,the kinetic pressure after the mixing of the air and pulverized coal and that of the primary air (exhaust gas) prior to the above mixing,can represent the magnitude of pulverized coal concentration in the pipeline.The method under discussion is applicable for measuring pulverized coal concentration in bin and feeder systems.
出处
《热能动力工程》
CAS
CSCD
北大核心
2009年第3期378-381,共4页
Journal of Engineering for Thermal Energy and Power
关键词
煤粉浓度
动能法
风粉混合
乏气送粉
pulverized coal concentration,kinetic energy method,air and pulverized coal mixing,pulverized coal feed by exhaust gas
