基于声学测温的水冷壁局部超温监测研究  

Local Overheating Monitoring of Water Walls Based on Acoustic Pyrometry

作　　者：张世平[1] 安连锁[1] 李庚生[1] 沈国清[1] 冯强[1] 邓喆[1] 

机构地区：[1]华北电力大学电站设备状态监测与控制教育部重点实验室,北京102206

出　　处：《动力工程学报》2012年第4期302-307,共6页Journal of Chinese Society of Power Engineering

基　　金：国家自然科学基金资助项目(50976034);中央高校基本科研业务费专项资金资助项目(09QG43)

摘　　要：以理论和试验相结合的方法,对锅炉热态时水冷壁附近的温度场及声线分布进行了研究,开发了基于声学测温的水冷壁局部超温监测系统,并在国内某300MW锅炉机组上进行了试验研究.结果表明:声学测温技术应用于水冷壁局部超温监测是完全可行的;锅炉热态时,水冷壁附近的声线会朝着炉膛内高温侧发生弯曲;系统测得的烟气温度作为基准量能很好地反映水冷壁向火侧壁面温度的变化情况;线性扫频信号可以作为监测系统的声源信号,扫频区间在500～3 000Hz为宜;此系统中,互相关时延估计法能准确地计算出声波飞渡时间.The temperature field and acoustic ray distribution near water wall of a boiler were studied at hot state theoretically and experimentally, after which a local overheating monitoring system was developed based on acoustic pyrometry and subsequently tested in a domestic 300 MW boiler unit. Results show that it is completely feasible for acoustic pyrometry to be applied for local overheating monitoring of water walls; the acoustic ray near water wall bends toward high-temperature side in the furnace at hot-state; as a reference standard, the flue gas temperature measured by the system can accurately react the temperature variation of water wall on the side facing the fire; linear sweep signal can be taken as the sound source in a- coustic pyrometry, and the best frequency range is found to be within 500--3 000 Hz; via cross correlation time delay estimation （TDE） method adopted in the system, the flight time of acoustic wave can be calcu- lated accurately.

关 键 词：水冷壁 声学测温 超温 线性扫频信号 声线 

分 类 号：TK224[动力工程及工程热物理—动力机械及工程]