烧蚀炭化热防护材料热导率的贝叶斯辨识方法  

Bayesian identification of thermal conductivity for charring ablative thermal protection materials

作　　者：林旭文 高博[1] 易法军[1] 杨强[1] 疏浩 Lin Xuwen;Gao Bo;Yi Fajun;Yang Qiang;Shu Hao(National Key Laboratory of Science and Technology on Advanced Composite in Special Environments,Harbin Institute of Technology,Harbin 150080,China)

机构地区：[1]哈尔滨工业大学特种环境复合材料技术国家级重点实验室,哈尔滨150080

出　　处：《空天技术》2022年第3期18-30,70,共14页Aerospace Technology

摘　　要：烧蚀炭化材料热导率对热防护结构的温度分布、进入材料内部的净热流以及热应力分布具有重要影响,提出了一种基于动态贝叶斯网络(DBNs)的炭化材料热解过程热导率的辨识方法。在该方法中,利用全局敏感性分析方法获取各参数在整个升温过程的主要影响区间,在各区间内仅求解相应敏感参数,减少同时辨识的参数个数。将该方法用于TACOT材料热导率辨识,数值算例结果表明,稀疏化后的DBNs使最大辨识误差降低为5.68%,温度复现的均方根误差降低了45.01%,且算法具有较好的稳定性,在考虑观测温度0.8%的高斯噪声下,变异系数仅为0.16。该方法可以进一步应用于求解烧蚀炭化热防护材料的其他参数、辨识结构边界所受气动热环境。The thermal conductivity of charring ablative material has an important impact on the temperature distribution of thermal protection structure,the net heat flow into the material,and the distribution of thermal stress.An identification method based on dynamic Bayesian network(DBNs)is proposed,which is used to identify the thermal conductivity of charring materials in pyrolysis process.In this method,using the global sensitivity analysis method to obtain the main influence intervals of the parameters in the whole heating process,and only solve the corresponding sensitive parameters in each interval,reducing the number of parameters identified simultaneously.The method is applied to the thermal conductivity identification of TACOT materials.Results of the numerical examples show that,the sparse DBNs method reduces the maximum identification error to 5.68%,and the root mean square error of temperature recurrence by 45.01%.Moreover,the algorithm has good stability,the variation coefficient is only 0.16,considering the Gaussian noise that standard deviation is 0.8%times observed temperature.This method could be further applied to identify other parameters of the charring ablative thermal protection materials,as well as to determine the aerodynamic thermal environment of the structure boundary.

关 键 词：烧蚀炭化材料 参数辨识 动态贝叶斯网络 全局敏感性分析 热导率 热解过程 

分 类 号：V19[航空宇航科学与技术—人机与环境工程]