Theoretical impact failure distribution of granules

A two-parameter Weibull distribution is presented that predicts the number of undamaged granules after impact with a rigid surface (platen) as a function of the impact velocity. The Weibull distribution is fitted, using experimental results from the breakage of fertilizer granules, to find the two parameters. The number of undamaged granules can be found using the velocity and angle of impact. A theoretical model derived by Maxim et al. is used to define a failure velocity as the criterion for failure. This model allows the theoretical prediction of the impact velocity required to induce 63.2% failure (c parameter in the Weibull distribution) from knowledge of measurable granule and platen material properties.