A comprehensive study is reported on the dynamics of critical components in the refueling process for passenger cars and light trucks. Nozzle, filler pipe, recirculation tube, tank, and canister are investigated. CFD simulations are conducted for flow rates of 4 liters/min (lpm) to 80 lpm for gasoline and up to 120 lpm for diesel fuel. Tank pressure, identified as a critical parameter controlling flow performance, is measured and utilized as a boundary condition. Flow simulation in a carbon canister, accomplished by treating the adsorbing carbon as a porous medium, indicates pressure drops which are in good agreement with published experimental data. Experiments have been conducted and used to validate simulation results. The simulations indicate that CFD can be successfully utilized as a tool to shorten the design, development and cost reduction cycle of a nozzle, filler pipe, canister, and tank system. Copyright © 2002 Society of Automotive Engineers, Inc.