Topic C56-17: Wide-Area, Rapid Vacuum Bag Leak Detection for Composite Wind Turbine Blade Fabrication

Composite structures such as wind turbine blades are cured under vacuum as a key manufacturing step. Vacuum bag leaks during the production of composite components can cause significant delays in the manufacturing process, and in some cases can even cause damage that must be later repaired. Because of the large scale of these structures, incremental improvements to manufacturing processes can have significant cost effects.Solution. PD3 will develop a system which allows for rapid and accurate leak checking of vacuum bags, and the precise location of leaks, using a novel camera system to detect leaks by sensing an embedded sensor chemical incorporated in the vacuum bag that provides a visual indication of the pressure level under UV illumination. The operator will use a camera and software application on a commercially available tablet or smartphone to take an image, and automatically process it to create a pressure map of the surface of the vacuum bag. The “false color image” will be indicative of pressure and allow immediate detection and correction of leaks. Rapid location of leaks has been repeatedly highlighted as a technical problem in aerospace composite manufacturers and their customers. These technologies can be applied and improved to aid in the manufacture of large wind turbine blades.Phase I Work Plan. In Phase I we will develop the rapid image-analysis methodology, building on a proof of concept already completed, and IOS/Android applications to perform the image analysis rapidly and in real-time. We will concurrently develop an extruded or film-coated product that incorporates the indicator material into a vacuum bag film or a separate tape product, allowing precision location of vacuum leaks in conjunction with the image analysis software.Commercial Applications and Other Benefits. This technology will benefit manufacturers of wind turbine blades by improving process yields and elimination of costly repairs. PD3 has had initial commercial and technical discussions with a large supplier of composite materials and consumable supplies to wind turbine blade manufacturers, who will potentially distribute the product when commercial production commences. The technology can also benefit other manufacturers of composite structures in aerospace and marine applications.