某总温总压受感器热电偶结构优化设计  

Improving design and study on the thermocouple structure of a total temperature and total pressure sensor

作　　者：张卓利 王佳伟 董伟超 黄开放 ZHANG Zhuoli;WANG Jiawei;DONG Weichao;HUANG Kaifang(Chinese Flight Test Establishment,Xi’an 710089,China)

机构地区：[1]中国飞行试验研究院,陕西西安710089

出　　处：《中国测试》2023年第12期73-78,共6页China Measurement & Test

摘　　要：该文针对某总温总压受感器在振动试验过程中K型铠装热电偶断裂的故障,进行原因分析和改进。将铠装热电偶更换为带编织绝缘层的K型热电偶,采用双孔瓷管作为热电偶丝和壳体之间的绝缘和固定元件,设计尾部电缆固线套。通过模拟仿真和数值计算的方法对时间常数指标进行分析,采用增大总温总压受感器阻滞腔排气孔尺寸的方法,将阻滞腔内平均内流速度由22.047 m/s提高到41.835 m/s,计算理论时间常数由1.01 s降为0.688 s。通过温度特性校准,受感器测量精度满足Ⅰ级K型热电偶的精度要求;经时间常数试验校准,在来流马赫数Ma为0.3,高度H为0条件下,时间常数变化范围为0.860~0.930 s;通过强化振动循环试验验证,产品功能性能正常,提高了产品可靠性。In view of the K-type armored thermocouple wires of the total temperature and total pressure sensor(TTAPS)was broken during the vibration test,the cause of the failure was analyzed and the designment scheme was improved.The armored thermocouple was replaced with a kind of K-type thermocouple which has braided insulation casing,a double-hole ceramic tube were used as the insulation and fixing element between the thermocouple wires and the TTAPS,and a kind of tail cable fixing structure was designed.The time constant was analyzed through simulation and theoretical calculation,by increasing the size of the exhaust holes in the TTAPS’s block chamber,the average airflow velocity in the block chamber was increased from 22.047 m/s to 41.835 m/s,and the theoretical time constant was calculated to decrease from 1.01 s to 0.688 s.Through temperature characteristic calibration,the measurement accuracy of the TTAPS reachs the requirements of Class I K-type thermocouple.Through temperature characteristic calibration,under the condition of Mach number 0.3 and altitude H=0,the variation range of time constant is 0.860 s to 0.930 s.The enhanced vibration cycling test has verified that the functional performance of the TTAPS is normal,it is indicated that the TTAPS’s reliability was improved.

关 键 词：铠装热电偶 时间常数 阻滞腔 内流速度 

分 类 号：V241.7[航空宇航科学与技术—飞行器设计]