ABSTRACT This study presents a modelling approach to the study of the submicron particle agglomeration process under different conditions of ultrasonic exposure (in both the sinusoidal-wave mode and shock-wave (pulse) mode). For the modelling the non-linear effects occurring under the shock-wave action and influencing the particle coagulation rate are evaluated (pulse transferring, changing of effective cross-section collision by Brownian motion and shock-wave pressure drop, changing of particles concentration). For the first time, the model simultaneously accounts for the non-linear effects. The research conducted has revealed the optimum duration of shock pulses of compression and depression. It has been demonstrated that the shock-wave mode allows up to 20 times rate of submicron particle coagulation as compared to the sinusoidal-wave with the same total energy of action.