Vakum destekli reçine transfer kalıplama (VARTM) yönteminde parça kalınlığının izlenmesi ve modellenmesi

This thesis successfully uses Structured Light Scanning (SLS) to monitor a composite part's thickness distribution as it is being manufactured with Vacuum Assisted Resin Transfer Molding (VARTM). As resin is infused through a porous fabric preform, local resin pressure and thus compaction pressure acting on the preform change causing thickness to vary spatially and with time. Integration of SLS system with a VARTM setup also allows to conduct compaction characterization of fabric preforms. SLS full-field thickness monitoring allows to record statistical variations and thus superior to instruments such as dial gages which measure thickness at a point only. After the mold is filled with resin, the injection gates are closed, and vacuuming is continued through the ventilation ports to see the effect of resin bleeding. This action evacuates excess resin out and settles pressure with time. Thickness decreases from 1.72+/-0.27 mm just before closing the inlet to 1.55+/-0.17 mm 300 s later in 2D experiment. Corresponding fiber volume fraction increases from 0.19+/-0.03 to 0.21+/-0.02, thickness variation decreases from 2.32 to 1.55 mm, respectively. Resin pressure and part thickness are modeled and compared with the experimental data in 2D resin flow case. Resin pressure is solved by discretizing continuity equation (Darcy velocity components substituted in mass conservation equation) using Finite Difference Method. At the steady state, the difference between simulated and experimental flow rates through inlet is 0.5% showing that the material characterization, flow and compaction modeling are useful tools to predict resin flow as well as part thickness distribution.