固体结构内部瞬态非均匀温度场的重建方法研究

固体结构内部瞬态非均匀温度场的无损测量在航空航天、机械制造、材料加工和医疗卫生等领域都具有十分重要的作用。基于超声波脉冲回波法，建立了超声测量各向同性均匀介质结构内部瞬态温度分布的理论模型，发展了预测结构内部非均匀温度场的灵敏度法和共轭梯度法，并系统比较分析了两种瞬态温度场重建算法的精度、抗噪性和稳定性等特性。实验验证表明：基于热传导反问题的两种方法，重建得到的结构内部瞬态非均匀温度分布精度均较高，实时性好，适用性强；对结构内部瞬态温度场的预测与评估以及探索研究结构内部量的新型测量和控制技术等具有参考意义。固体结构内部瞬态非均匀温度场的无损测量在航空航天、机械制造、材料加工和医疗卫生等领域都具有十分重要的作用。基于超声波脉冲回波法，建立了超声测量各向同性均匀介质结构内部瞬态温度分布的理论模型，发展了预测结构内部非均匀温度场的灵敏度法和共轭梯度法，并系统比较分析了两种瞬态温度场重建算法的精度、抗噪性和稳定性等特性。实验验证表明：基于热传导反问题的两种方法，重建得到的结构内部瞬态非均匀温度分布精度均较高，实时性好，适用性强；对结构内部瞬态温度场的预测与评估以及探索研究结构内部量的新型测量和控制技术等具有参考意义。

Reconstruction of Transient Nonuniform Temperature Field in Solid Structures Using Inverse Methods

A new method is presented for reconstruction of internal transient nonuniform temperature field in solid structures . The proposed method consists of a joint of heat conduction calculation and an inverse analysis for boundary parameter estimation using ultrasonic time of flight by conjugate gradient method or sensitivity method. The principle for internal temperature sensing is based on temperature dependence of the velocity of ultrasonic wave that propagates through solid material. Serial simulation and stability analysis are made， in which classic function form of heat flux or constant temperature is estimated to illustrate the calculating accuracy and the factors of influencing two parameter estimation methods. Comparison experiments with a steel plate which single side is heated by hot water are referred. The temperature gradient and its variation estimated by the two methods agree well with the data measured using thermocouples installed in a steel structure. The results show that the proposed method is a promising means for high accurate reconstruction of internal transient temperature field in solid structure.