Analysis of factors influencing micro-scale double-bubbles collapse based on molecular dynamic simulation

Abstract

The collapse of bubbles in hydraulic machinery has emerged as a prominent area of research. To grasp the interplay between bubbles, a model of double-bubbles is built. The bubble morphology, total pressure (P), and the center of mass displacement (L_com) are taken as research objects, and the influence temperature (T), and bubble radius (R), bubble distance (L) on bubble collapse is summarized. Results show that the distance between the bubbles is smaller, the total collapse time is longer. However, L_com increases when the distance is increased or decreased to some extent. Moreover, in the case of the double-bubbles model with r₁ = 10 Å, as the bubbles (r₂ = 7.5, 10, 12.5 Å) collapse, the released pressure gradually increases, then decrease, and the release pressure of the double-bubbles model (r₁ = 10 Å, r₂ = 12.5 Å) is 1.08 times that of the model (r₁ = 10 Å, r₂ = 15 Å). Based on the differential pressure parameters (∆P₁ and ∆P₂), the significance order of temperature (T), bubble distance (L), and bubble radius (r) is L ≈ r > T. The aim of the paper is to provide technical guidance and a theoretical basis for industrial applications of techniques by enhancing the theory of cavitation.