Parametric analysis of adhesive squeeze flow with large substrate roughness patterns

In this work, a numerical framework was developed to investigate the effects of several physically relevant parameters on adhesive squeeze flows. Simulations used OpenFOAM with the Volume-of-Fluid method and Piecewise-Linear Interface Construction to track the adhesive–air interface and fluxes. The adhesive was modeled as a shear-thinning Bird-Carreau–Yasuda (BCY) fluid, and the surface roughness as idealized, pronounced micrometric rectangular patterns. Their widths and heights were varied, alongside physical properties including viscosity, BCY relaxation, contact angles, and adhesive-air surface tension coefficients. The impacts on flow evolution, reaction forces, dissipation rates, wetted areas, viscosity distributions, front velocities, and air flows within the surface features are analyzed. The results indicate that deep textures exacerbate air entrapment by shielding fluid from shear, whereas surface tension and rheology strongly correlate with wetting efficiency. Consequently, prioritizing high shear-thinning and interfacial tension over geometric modifications involving periodic rectangular patterns is recommended; however, if such textured substrates are unavoidable, narrower channel widths and shallower heights might be a superior design choice for hindering bubble formation and air buildup in the regular groove setting modeled. These findings further the understanding of physical variables in the squeeze regime and contribute to the predictive understanding of adhesion during joint manufacturing.