Abstract: Fiber‑reinforced polymer composites are increasingly critical in sectors like aerospace wind energy and transportation with excellent specific strength and specific modulus. As components evolve toward larger sizes and greater complexity manufacturing processes face stringent demands for efficiency cost‑effectiveness and quality stability. Vacuum‑assisted resin infusion VARI as a mainstream low‑cost liquid composite molding technique has become the preferred solution for the production of large‑scale components. However the quality of these components is intrinsically governed by the resin' s impregnation efficiency into the fibrous preform and improper flow control often leads to defects such as dry spots and microscopic voids thereby limiting the improvement of component performance. Therefore precisely adjusting the rheological characteristics of the resin and deeply understanding its permeation mechanism are key to overcoming the quality bottlenecks of this process. This review examines the physical correlations between viscosity evolution and multi‑scale impregnation quality. Macroscopically resin flow is described by Darcy' s law with corrections for non‑Newtonian behaviour in nano‑modified systems. Microscopically the competition between viscous and capillary forces defined by the modified capillary number criterion establishes an optimal processing window to minimise defects. Chemo‑rheological models provide the theoretical basis for predicting flow fronts and gelation. To achieve a low initial viscosity and a long processing window the paper systematically summarizes chemical and physical regulation strategies. Chemically molecular design and reactive diluents reduce intrinsic viscosity while latent curing agents maintain a low‑viscosity state before triggered cross‑linking. Physically the review compares heating methods highlighting the limitations of traditional oven curing and the advantages of field‑assisted techniques like microwave and induction heating. Special emphasis is placed on "Out‑of‑Oven" technologies such as self‑regulating Joule heating and Frontal Polymerization which enable energy‑efficient in‑situ curing. Beyond rheology synergistic enhancements are discussed including optimised pressure fields to improve compaction and permeability and the development of sustainable bio‑based flow media. The trend towards structural‑functional integration is also noted where consumables like conductive meshes are transformed into permanent functional layers of the component. At the digital level process numerical simulation has evolved into a multiphysics coupling model encompassing flow heat transfer and curing which can be accelerated through integration with machine learning. Meanwhile various in‑situ monitoring techniques provide data support for closed‑loop control. Looking ahead the VARI process is expected to follow three major development trends green manufacturing centered on oven‑free curing and eco‑friendly consumables intelligent manufacturing based on digital twins and integrated manufacturing that deeply combines process and functionality. This comprehensive review aims to provide theoretical guidance and technical pathways for the high‑quality sustainable and cost‑effective manufacturing of advanced composite structures.

Key words: vacuum?assisted resin infusion VARI , chemo?rheology, out?of?oven curing , multi?scale simulation, digital twin

摘要： 真空辅助树脂灌注成型(VARI)中树脂流变行为与多尺度浸润过程的耦合机制,是制约大型高性能复合材料构件成型质量的关键因素。 围绕液态成型过程中的物理机制与调控方法,综述了 VARI 工艺中树脂流变调控及其对渗透行为的影响。 基于化学流变学模型与修正毛细数理论,阐明了树脂黏度演变与宏观流动前沿及微观孔隙填充的关联,并分析了纳米改性体系的非牛顿特性。 总结了通过分子设计、潜伏性固化 及活性稀释剂实现低黏度与长工艺窗口的调控策略,重点讨论了热传递及场辅助加热对黏度场的调控作用,并介绍了自调节电阻加热与前沿聚合等内生热技术。 此外,概述了多物理场耦合仿真与原位监测在工艺表征中的应用进展。 最后指出,VARI 正由经验驱动向机理驱动转变,结合原位监测与高保真模拟的数字孪生方法,有望实现跨尺度协同调控,提升复杂构件成型质量。

关键词: 真空辅助树脂灌注成型(VARI), 化学流变学, 炉外固化, 多尺度模拟, 数字孪生