ANALYSIS OF RESIN TRANSFER MOLDING WITH HIGH PERMEABILITY LAYERS

In resin transfer molding (RTM) a high permeability layer (HPL) is pla ced on tap of the fiber mat lay-up to reduce mold filling time and inc rease the ultimate distance resin cart be drawn into the mold. HPL's a re particularly useful in vacuum bag resin transfer molding (VBRTM), w here driving pressures are relatively low. When compared to traditiona l closed mold RTM, VBRTM has the advantages of low capital costs and s hort start up time. The goal of the current research is to investigate how an HPL can be used to improve quality and process efficiency for parts of complex geometry made by both conventional nr rd vacuum bag R TM. As a first step towards this goal, the effect of the HPL on the fl ow field has been studied through analysis, experiment and simulation. As expected, the use of the HPL creates a transverse (i.e., top-to-bo ttom) pow in the fiber mat, facilitating mold filling. The thickness o f the HPL has been varied to determine the effects on the flow front. The experimental results validate the capability of the simulation to model two-dimensional flow in a porous medium with heterogeneous perme ability.