
2016年第35卷第6期
传感器与微系统(Transducer and Microsystem Technologies)
9
DOI:10. 13873/J.10009787( 2016 )06000904
三轴一体IMU组件中光纤环热分析
刘弘毅,宋来亮,张春嘉
(北京航空航天大学器科学与光电工程学院,北京100191)
摘要:对某型号三轴一体光纤陀螺捷联惯导系统建立有限元模型,从结构角度分析了惯性测量单元(IMU)中光源和加速度计等发热模块对光纤环温度场分布的影响。分析研究IMU组件在22℃常温稳态下的传热规律,表明光源与加速度计等热源所产生热量将不以传导方式在箱体与IMU台体之间传递,对流与辐射传热对IMU温度分布影响较大;光源为主要热源,是造成Y,Z轴光纤环温度分布不均匀的主要原因;加速度计发热将影响X轴光纤环温度分布。通过+60℃高温瞬态热分析,研究光纤环在极端环境下温度变化规律,表明系统在极端环境下随着温度上升而温度梯度递减,光纤环瞬态温差增大。稳态和瞬态热分析可指导惯导系统IMU部分结构热设计的改进
关键词:三轴一体光纤陀螺;惯性测量组件;光纤环;热分析
中图分类号:TP391.9
文献标识码:A
文章编号:1000-9787(2016)060009-04
Thermal analysis of fiber coil in three-axis integration IMU
LIU Hong-yi, SONG Lai-liang, ZHANG Chun-xi
( School of Instrumentation Science& Opto-electronics Engineering,
Beihang University,Beijing 100191,China)
Abstract: Influence of heating modules such as light source and accelerometer in inertial measurement unit( IMU ) on temperature field distribution of fiber coil is analyzed from structure perspective, finite element model( FEM for a certain type of three-axis integration optical fiber gyro strapdown inertial navigation system( INS ) is established. Analyze and study heat transferring rule of IMU under the condition of room temperature( 22 °C )and steady state, which indicates that the heat generated by light source and accelerometer can not be transferred from box to IMU in the way of heat conduction, and influence of convection and radiation on temperature field distribution of IMU is great. Light source is the principal heating source which is the main reason affects nonuniform of temperature distribution of Y and Z axis fiber coil , and temperature distribution of fiber coil in X axis is influenced by heating of accelerometer. Through high temperature( 60 °C ) trans thermal analysis, study on temperature variation rule of fiber coils under the condition of extreme environment, it indicates that temperature gradient declines when temperature rises, fiber loop transient temperature difference increase in harsh environment. Both steady and transient thermal analysis can guide improvement of thermal designs of IMU paitial structure of INS
Key words: three-axis integration fiber-optic gyroscope( FOG ); inertial measurement unit( IMU ); fiber coil; themal analysis
引言 0
光纤捷联惯导系统(fiber strapdown inertial navigation system,FINS)具有高精度、高可靠性、低功耗等优点,已获得了大量应用1.2)。在某些应用场合要求光纤陀螺(fiber-optic gyroscope,FOG)具有较宽的工作温度范围(如-40~ +60℃),要求FOG必须具有宽温域下的高输出稳定性。而FOG中主要器件如光纤环等对温度较为敏感;当环境温度发生变化时,FOG输出信号中存在非互易相位误差,影
收稿日期:2015-10-01
响其在不同温度条件下的检测精度[3.4]。因此.在FINS结构设计过程中必须充分考患系统和光纤环等部件的温度分布与变化规律,以减小温度场对FOG性能的影响,提高 FINS导航精度。
本文以某型FINS为基础,建立了系统热场模型,分析了惯性测量组件(inertialmeasurementunit,IMU)所处热环境,研究了系统内热源对组件温度分布的影响和极端环境下系统温度变化规律。仿真结果可为系统结构设计提供有