Experimental study of tube-wall temperature measurements in CFB boilers by embedding thermocouples using deposited metal
YAO Yuge1,2, LÜ Junfu1,2, ZHANG Yang1,2, CHEN Shujie1,2, ZHANG Man1,2, YANG Hairui1,2
1. Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China;(; 2. State Key Laboratory of Control and Simulation of Power System and Generation Equipments, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China
Abstract:Heating surface tube-wall temperatures are key parameters for boiler safety. The high solids concentration in circulating fluidized bed (CFB) boilers complicates installation of thermocouples in the furnace or the fluidized bed heat exchanger. This paper describes a method for embedding thermocouples using deposited metal to measure the tube-wall temperatures in CFB boilers. The method was evaluated experimentally with two deposition shapes with the heat transfer between the thermocouple and the tube-wall analyzed to calculate the actual tube-wall temperature without the deposited metal. The results show that the differences between the measured and actual temperatures of the tube-wall without the deposited metal for the two deposition shapes were about ±3℃ and ±7℃ for various working conditions. Thus, this method can be applied to measure tube-wall temperatures in CFB boilers.
姚禹歌, 吕俊复, 张扬, 陈书洁, 张缦, 杨海瑞. 热电偶熔敷埋设法测量CFB锅炉壁温的实验研究[J]. 清华大学学报(自然科学版), 2019, 59(4): 326-330.
YAO Yuge, LÜ Junfu, ZHANG Yang, CHEN Shujie, ZHANG Man, YANG Hairui. Experimental study of tube-wall temperature measurements in CFB boilers by embedding thermocouples using deposited metal. Journal of Tsinghua University(Science and Technology), 2019, 59(4): 326-330.
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