Smoothed particle hydrodynamics modeling and experimental validation of pressure-driven microchannel filling

The filling of microchannels represents a challenge from both the physical-mathematical and computational perspectives due to the inherent complexity of the phenomena involved, such as the solid–fluid interaction and inertial forces. In this paper, we propose a novel numerical approach to study the filling phenomenon and the dynamic of a fluid-air interface (front) advancement based on the smoothed particle hydrodynamics (SPH) method. We implemented a modified hydrostatic pressure within SPH simulations intended to generate an artificial fluid column that drives the fluid through the microchannels, thereby mimicking and controlling the microchannel filling process. The simulation results are successfully compared with an analytical model and experimental measurements, demonstrating that both experiments and simulations closely match the analytical solution. These findings highlight the robustness of the model and the experimental methodology employed while also demonstrating the ability of the SPH method to represent the pressure-driven filling phenomenon in microchannels realistically.