煤粉浓度与风量的热探头测量方法研究  

Measurement of Air Flow and Concentration of Pulverized Coal with Two Ellipse-Shaped Thermal Probes

作　　者：刘磊[1] 王燕[1] 周芳德[1] 钱华[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2008年第1期23-26,共4页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(50376068)

摘　　要：开发了长弦为10 mm、短弦为5 mm的椭圆型热探头,用于煤粉浓度与风量的测量.将热探头放入煤粉-空气输送管中,热探头1的长弦平行于来流,热探头2的短弦平行于来流.研究发现:热探头1对煤粉浓度反应迟钝;热探头2对煤粉浓度反应比较敏感.分析了气固两相流中的弛豫效应,提出了热探头1和热探头2在气固两相流中的换热准则关系式.将热探头1和热探头2的换热准则关系式相耦合,可用于测量煤粉浓度和风量,测量结果的相对偏差分别在20%和10%以内.Two ellipse-shaped thermal probes are developed to measure the pulverized coal concentration and the air flow rate in a horizontal pneumatic pipe. The longer chord is 10 millimeter and the shorter chord is 5 millimeter for the thermal probes. The probe 1 is mounted in the pipe with its longer chord parallel to flow direction and the probe 2 is mounted with the shorter chord parallel to flow direction. It is found that the probe 1 has obscure response to the concentration of pulverized coal, while the probe 2 gets remarkable. The momentum response and the thermal response in gas-solid two-phase flow are analyzed for the probes. The revised Reynolds number and the revised Nusselt number are put forward. The dimensionless correlations are obtained for de- scription of the heat transfer performances of the probes. The results show that the flow rate of air and the concentration of pulverized coal can be measured with these two coupled thermal probes. The relative biases are within 20% and 10% for coal concentration and air flow, respectively.

关 键 词：两相流 热探头 煤粉 风量 测量 

分 类 号：TK39[动力工程及工程热物理—热能工程]