This application model uses Barracuda Virtual Reactor to simulate the filtration of formation sand through a standalone sand screen in a wellbore geometry. The sand screen is represented as a baffle with a particle size dependent pass-through probability rather than resolved geometrically, allowing field scale simulation of screen performance. The simulation captures the size resolved retention behavior of the screen, comparing inlet and outlet particle size distributions to quantify how effectively the screen filters a realistic, polydisperse formation sand, providing a framework for evaluating screen selection and completion design ahead of deployment.