Carbon fiber reinforced polymer (CFRP) composites are becoming popular due to their superior strength to weight ratio and stiffness properties. This study highlights the interlaminar debonding growth, which is considered one of the most frequent problems with composite materials. A three-blade horizontal axis water turbine (HAWT) was manufactured using IM7/Cycom5320-1 carbon/epoxy prepreg. During the process of manufacturing, a specific number of Teflon sheets were placed between the composite layers in two locations to create a separation between the layers and to investigate the delamination growth. Three different laminate stacking sequences were selected to be tested: [0°]4, [0°/90°]S, and [45°/−45°]S. The composite blades were placed in a water tunnel and run for 3 million revolutions. A thermography analysis was carried out to evaluate the propagation and growth of the delamination. A one-way fluid–structure interaction (FSI) model was created and implemented to obtain the stress values along the blade. The results showed the influence of the composite lay-up orientation on the growth of the delamination. The unidirectional blades ([0°]4) showed the lowest amount of propagation, while the cross-ply ([0°/90°]S) showed the most delamination growth. The bottom location (near the root) showed the maximum delamination. Both sides of the blades showed significant delamination growth. However, the back side showed more interlaminar debonding growth than the front side. After three million revolutions, the percentage of debonding growth for the bottom/back side of the blades was 6.58%, 36.25%, and 27.63% for [0°]4, [0°/90°]S, and [45°/−45°]S, respectively.

中文翻译：

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水平轴水轮机复合材料叶片层压板脱粘研究

碳纤维增强聚合物 (CFRP) 复合材料因其卓越的强度重量比和刚度特性而变得流行。这项研究强调了层间剥离生长，这被认为是复合材料最常见的问题之一。三叶片水平轴水轮机 (HAWT) 使用 IM7/Cycom5320-1 碳/环氧树脂预浸料制造。在制造过程中，特定数量的特氟龙板被放置在两个位置的复合层之间，以在层之间产生分离并研究分层增长。选择了三种不同的层压堆叠顺序进行测试：[0°]4、[0°/90°]S 和 [45°/-45°]S。复合材料叶片被放置在水隧道中并运行 300 万转。进行热成像分析以评估分层的传播和增长。创建并实施单向流固耦合 (FSI) 模型以获得沿叶片的应力值。结果表明复合材料铺层取向对分层增长的影响。单向叶片 ([0°]4) 表现出最低的传播量，而交叉层 ([0°/90°]S) 表现出最大的分层增长。底部位置（靠近根部）显示最大分层。叶片的两侧都显示出明显的分层增长。然而，背面比正面表现出更多的层间剥离生长。三百万转后，叶片底部/背面的脱粘增长百分比分别为[0°]4、[0°/90°]S、6.58%、36.25%和27.63%，