Assessment of Non-adiabatic Behaviour in Thermoelastic Stress Analysis of Composite Sandwich Panels
Assessment of Non-adiabatic Behaviour in Thermoelastic Stress Analysis of Composite Sandwich Panels
复制标题
复合夹芯板热弹性应力分析中非绝热行为的评估
DOI：
10.1007/s11340-012-9601-9
复制
发表时间：
2012
影响因子：
2.4
通讯作者：
J. Dulieu‐Barton
中科院分区：
文献类型：
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作者：
D. Crump;J. Dulieu‐Barton
采用热弹性应力分析法（TSA）对大型蜂窝夹芯碳纤维面板夹层结构板的表面应力进行了分析。夹层板是飞机辅助结构中的典型。使用定制设计的试验装置，使板经受与使用中经历的压力载荷类似的压力载荷。为了达到TSA所需的绝热条件，循环加载被认为是一个基本特征。由于面板是全尺寸的，因此可以通过试验台赋予面板的最大负载频率为1 Hz，这低于为实现绝热行为而推荐的通常范围。为了评估TSA的有效性，在低频率的两种校准方法进行了研究，并与独立验证的有限元模型获得的应力分布进行了比较。热弹性响应被校准到应力数据使用热弹性常数从夹层板面板材料的拉伸条实验得出。它示出，通过使用热弹性常数从制造与相同的铺层作为夹层板面板的拉伸条，并在相同的循环载荷频率在全尺寸测试中使用，定量应力度量可以来自TSA数据。更重要的是，更深入地了解层压材料的TSA中的热特性的重要性。它表明，在这项工作中使用的材料，它是可以使用的全球材料的行为，以获得定量的结果时，绝热条件不占上风。
Thermoelastic stress analysis (TSA) is used to derive the surface stresses in large sandwich structure panels with honeycomb core and carbon fibre face sheets. The sandwich panels are representative of those used for secondary aircraft structure. The panels were subjected to a pressure load, similar to that experienced in-service, using a custom designed test rig. To achieve the necessary adiabatic conditions for TSA, cyclic loading is regarded as an essential feature. As the panels were full-scale, the maximum loading frequency that could be imparted to the panels by the rig was 1 Hz, which is below the usual range recommended to achieve adiabatic behaviour. To assess the effectiveness of TSA at low frequencies two approaches to calibration are investigated and compared with the stress distribution obtained from independently validated FE models. The thermoelastic response was calibrated into stress data using thermoelastic constants derived experimentally from tensile strips of the sandwich panel face sheet material. It is shown that by using thermoelastic constants obtained from the tensile strips manufactured with the same lay-up as the sandwich panel face sheets, and at the same cyclic load frequency used in the full-scale tests, quantitative stress metrics can be derived from the TSA data. More significantly, a deeper insight into the importance of the thermal characteristics in TSA of laminated materials is provided. It is demonstrated that, for the material used in this work, it is possible to use the global material behaviour to obtain quantitative results when adiabatic conditions do not prevail.