Improved models for fractal colloidal agglomeration: computationally efficient algorithms

New probability distribution functions for aggregates produced in non-uniform discrete coagulation modeling were derived and incorporated into the population balance equations. These new algorithms made it possible to simulate fractal aggregate coagulation with high accuracy, perfect mass conservation and exceptional computational efficiency. Parameter sensitivity analysis showed that a break-up kernel does not influence total particle concentration within the limited range of having the break-up coefficient less than collision efficiency, but does influence the particle size distribution and coagulation patterns. An aggregate break-up study with various kernel parameters indicated that break-up rate is more influenced by particle volume and not size class or diameter as previously suspected. The new probability distribution functions are found to be useful in fractal aggregation modeling via the higher numerical stability and accuracy. The new particle population model (Eq. (17)) is shown in the investigation to be superior to all of the other models, having mass conservation factor of over 0.99 and computation time of 3.125 × 10−2 s, thus the new model of Eq. (17) can be used to develop predictive simulations for coagulation in computational fluid dynamics and reaction modeling.