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Evanescent Wave Fluorescence Fiber Optic Sensor for Flow Monitoring in Liquid Composite Molding



S R. Kueh, S G. Advani, Richard~undefined~undefined~undefined~undefined~undefined Parnas


On-line sensing can play an important part in controlling the quality of the final product in any manufacturing environment, including liquid composite molding (LCM). Having a sensor embedded within the part itself is often the most effective means of monitoring its condition at various stages of manufacturing and even throughout its useful life. However, given their intrusive nature, there are practical limitations imposed upon their size, quantity and trajectory within the part. The objective of this study is to explore the possibility of using an evanescent wave fluorescence fiber optic sensor to monitor the resin flow front during the mold filling stage of LCM, and to detect the onset of void formation and the presence of dry spots within the mold. Experiments were initially conducted to characterize the sensor response of such a detection system, followed by simulation work to determine the optimal placement of just one such sensor in a mold so that it will yield the most information on the mold filling process. The secondary goals of the simulation work were to learn how to interpret the sensor response and, subsequently, use it to control the LCM process.
Polymer Composites


fiber optic sensing, liquid composite molding, mold filling simulation, resin flow monitoring


Kueh, S. , Advani, S. and Parnas, R. (2021), Evanescent Wave Fluorescence Fiber Optic Sensor for Flow Monitoring in Liquid Composite Molding, Polymer Composites (Accessed May 22, 2024)


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Created October 12, 2021