Advancing damage and leakage prediction capabilities for pressure-retaining fibre-reinforced polymer composite structures

纤维增强聚合物复合材料(FRPC)具有比强度高、无腐蚀性等优良性能，可用于含压力流体的先进结构。应用很多，例如碳氢化合物精炼和升级中的工艺管道，其中腐蚀是一个相当令人担忧的问题；用于液化天然气等低温流体的管道，其要求管道的膨胀特性与绝缘结构相匹配；以及用于储存压缩气体燃料的无衬里轻质压力容器。 保压FRPC结构必须防止或抑制任何导致泄漏的损坏，即液体渗透到结构中和穿过结构。泄漏是由微损伤特征和裂纹网络引起的，这些微损伤特征和裂纹网络随着载荷大小和循环次数的增加而在聚合物基质中启动和扩展。尽管人们知道基本的损害机制，但人们普遍认为，需要进行更多的研究，才能进行可靠的泄漏预测。后者对于压力容器FRPC结构的成功设计至关重要，它在重量、耐久性、成本和安全性方面都具有优势。 作为拟议研究的一部分，实验和分析设备将与研究组关于材料和失效特征的知识库(从微观到宏观)结合使用，以识别与泄漏损害最相关的材料和损伤特性。随后的任务将是扩展现有的建模方法，或开发基于导致流体渗透的最普遍现象的新的数值、分析和/或统计预测方法。假设一种成功的方法需要捕捉基质相内的损伤效应，包括裂纹的连通性和开度，从而影响复合材料结构的渗透性。除了其科学和工业价值外，拟议的研究还将为多达10000名高素质人员提供高级培训。

Fibre-reinforced polymer composites (FRPC) possess attractive properties such as high specific strength and non-corrosiveness which may be exploited for advanced structures containing pressurised fluids. Applications are plentiful, e.g. process piping in hydrocarbon refining and upgrading, in which corrosion is a considerable concern; piping for cryogenic fluids such as liquefied natural gas, which requires pipe expansion characteristics that match those of the insulation structure; and linerless lightweight pressure vessels for the storage of compressed gaseous fuels. It is imperative that pressure retaining FRPC structures prevent or inhibit any damage that leads to leakage, which is the permeation of fluid into and through the structure. Leakage is caused by micro damage features and crack networks that initiate and grow in the polymer matrix with increasing load magnitude and cycles. Despite knowledge of the basic damage mechanisms it is widely recognized that additional research is needed to enable reliable leakage prediction. The latter is imperative for the successful design of pressure containment FRPC structures that provide advantages in terms of weight, durability, cost and safety. As part of the proposed research, experimental and analytical equipment will be employed in conjunction with the research group's knowledgebase on material and failure characteristics, which range from the micro to the macro scale, to discern material and damage properties that are most relevant to leakage damage. A subsequent task will be to expand existing modelling approaches or to develop new numerical, analytical and/or statistical predictive methods that are based on the most prevalent phenomena leading to fluid permeation. It is postulated that a successful methodology needs to capture damage effects within the matrix phase, including the connectivity and aperture of cracks and thus the permeability of the composite structure. In addition to its scientific and industrial value the proposed research will provide advanced training for up to 10 highly qualified personnel.