Investigation of pressure profile and flow progression in vacuum infusion process

Abstract

Analytical formulations for the pressure profile in rectilinear and radial flow vacuum infusion (VI) processes are developed. The coupled pressure formulations are solved using an iterative numerical procedure. As the formulations are coupled, reinforcement specific solutions need to be derived. The VI process is also modelled using a numerical flow simulation tool, using a previously reported approach. In addition, analytical formulations for fill times in the rectilinear and radial flow VI processes are developed. It is found that with increasing reinforcement compliance, the analytical VI pressure profile diverges from the resin transfer moulding (RTM) pressure profile. Results from numerical flow simulations show a similar behaviour. The error level in the numerical results of VI pressure solution depends on the reinforcement compliance. The fill times ratio, between equivalent RTM and VI processes, remains constant for rectilinear and radial flow processes. This allows one to use RTM flow simulation tools to model rectilinear and radial flow VI processes without any major modifications.