Pin-assisted resin infiltration of porous substrates

Abstract

We analyze computationally the process of pin-assisted resin infiltration of porous substrates. In such a process, a porous substrate is pulled over a staggered array of stationary pins. A wedge-shaped fluid region forms between each pin and the moving substrate and the generated pressure forces the resin to infiltrate into the substrate. The objective is to investigate any relationships between process characteristics (substrate speed, permeability and pin radius) and the extent of resin infiltration. Our results show that the infiltration depth in the limit of a dry substrate scales with K0.403 and R0.361. The effect of pin radius and of substrate permeability can be expressed by power functions of the dimensionless variables Lo/R and Lo/K. Finally, we suggest a scaling which, for a given pin radius, collapses all ΔLf data into one master curve described by the equation ΔLf=0.839K0.4031+0.271Lo/K0.986-1. The existence of such a relationship allows for the estimation of the sensitivity of the predicted infiltration depth on the relevant parameters, as well as for the design of a multi-pin process.