Lycopodium spore impacts onto surfaces

Experiments on oblique impact of Lycopodium spores with dry surfaces in the presence of adhesion were carried out. The experimental results are compared with those of stainless steel microsphere impact onto the same types of substrate surfaces. Three parameters are analyzed, the coefficient of restitution, the impulse ratio and the normalized kinetic energy loss and are used to represent the impact results. The comparisons show that the complex surface profile of a spore has a remarkable effect on impact response. The conjunction of the roughness of both the microparticle and the substrate make the impact mechanics even more complicated.