A Study on the Measurement System Design for the Resin Flow and Curing in the Vacuum Assisted Resin Transfer Molding(VARTM) Process Using the Long Period Fiber Bragg Grating

삽입된 장주기 광섬유 격자를 이용한 VARTM 공정에서의 수지이동 및 변형 과정 예측 시스템 설계에 관한 연구

  • Published : 2004.05.01


Long Period Gratings (LPG) is currently receiving considerable attention because of their consistent measuring results fur pressure, temperature, strain and flow. LPG is easier to prepare and has a high sensitivity compared with Fiber Bragg Gratings (FBG). In addition, this kind of optical fiber sensors could be used for implementations in various structures. In this paper, LPG was used to monitor in situ the resin flow and the curing process in VARTM (Vacuum Assisted Resin Transfer. Molding). In order to demonstrate the effectiveness of the method, FBG is inserted into the glass mat to monitor the resin flow using optical spectrum analyzer (OSA). The curing reactions in VARTM are also observed using the same method. From the results, the attenuation wavelength shift and the loss change of attenuation band can be obtained from the status of the RTM (Resin Transfer Molding) sample owing to the internal variations of the .effective index, temperature, and pressure. It is shown that the proposed LPG is more effective in monitoring the curing reaction than FBG.


Long Period Gratings(LPG);Fiber Bragg Grating(FBG);Resin Flow;Composite;Vacuum Assisted Resin Transfer Molding(VARTM);Optical Spectrum Analyzer(OSA)


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