Effect of turbulence on the disintegration rate of flushable consumer products

A previously developed model for the physical disintegration of flushable consumer products is expanded by investigating the effects of turbulence on the rate of physical disintegration. Disintegration experiments were conducted with cardboard tampon applicators at 100, 150, and 200 rotations per minute, corresponding to Reynold's numbers of 25 900, 39 400, and 52 900, respectively, which were estimated by using computational fluid dynamics modeling. The experiments were simulated with the disintegration model to obtain best-fit values of the kinetic and distribution parameters. Computed rate coefficients (k_i) for all solid sizes (i.e., greater than 8, 4 to 8, 2 to 4, and 1 to 2 mm) increased strongly with Reynold's number or rotational speed. Thus, turbulence strongly affected the disintegration rate of flushable products, and the relationship of the ki values to Reynold's number can be included in mathematical representations of physical disintegration.