Multiphysical modeling and optimization of vacuum bag only process with integration of resin flow, heat transfer and consolidation for composite manufacturing design

Official URL: https://risc01.sabanciuniv.edu/record=b2486472_(Table of contents)

The composite manufacturing for the aerospace industry requires advance and skillful manufacturing techniques. Autoclave manufacturing technique is well understood and widely used for the aerospace industry that aims to get as low as possible void content in cured parts with higher pressure and temperature profile. The allowable geometry of manufactured parts and operational cost limits Autoclave manufacturing techniques by fulfilling high mechanical performance. Alternatively, Out of Autoclave (OoA) technique with Vacuum Bag Only (VBO) method with right process conditions and prepreg system has the potential to displace expensive composite manufacturing challenges in the aerospace industry. The successful OoA manufacturing process depends on control of multiphysics such as resin flow, heat transfer and consolidation. In this thesis, integration of multiphysical governing equations scheme for VBO manufacturing process, is developed and implemented for 2D through thickness of 1-, 2-and 4-layer of OoA prepregs via commercially available software. This model aims to capture instantaneous void content in prepreg system, hence, void initiation mechanism and air evacuation channels during VBO process. The assessment of developed model during thesis, is planned to find time dependent change of resin impregnated area during VBO process. Based on change of resin impregnated area, the multiphysical assessment of developed model configurations is evaluated to reveal effective parameters of individual physics as well as integration with each other. The effective process parameters that includes initial cure temperature, post cure temperature, dwell time and ramp rate on the temperature profile is subjected to parametric numerical experiments as well as the optimization study with Nelder-Mead algorithm. The results of studies are aimed to find right process conditions in order to achieve repeatable, scalable and controllable VBO process outcomes