Experimental Investigation of a Particle-Laden Droplet Impacting a Cantilever Beam

Particle-laden droplets impacting deformable substrates are commonly encountered in practical applications, yet their coupled dynamics remain insufficiently understood. This study experimentally investigates the impact behavior of particle-laden droplets on superhydrophobic cantilever beams, with particular focus on the effects of particle concentration, Weber number (We), and beam stiffness. The results show that increasing particle concentration suppresses the maximum spreading diameter due to enhanced viscous dissipation and particle interactions, while at high concentration (φ = 50%) the droplet exhibits a more compact, solid-like rebound behavior. Despite these effects, the spreading time remains independent of all investigated parameters, indicating that the process is governed by the inertial-capillary time scale. The receding time is insensitive to particle concentration and We but decreases with increasing beam stiffness due to reduced structural deformation and energy dissipation. Consequently, the contact time is primarily regulated by substrate elasticity rather than particle-induced rheological effects. A scaling relationship for the contact time is established, revealing a nonlinear dependence on beam stiffness. Within the present parameter range (φ ≤ 50% and Oh ≪ 1), particle loading does not introduce a new governing time scale, and droplet dynamics remain dominated by the elastic response of the substrate. These findings provide new insights into multiphase droplet impact on deformable surfaces and offer guidance for the design of functional interfaces in applications such as anti-icing and spray processes.