Bubble dynamics: The role of acoustic pressure and temperature on stability and multifractality.

Environmental temperature significantly affects bubble dynamics. The temperature directly influences the liquid's surface tension, viscosity, and the bubble's spherical shape. These properties, in turn, affect the bubble expansion rate and collapse intensity. Thus, temperature plays a crucial role in the formation, growth, and collapse of bubbles. This study investigates the radial oscillation stabilities of microbubbles, considering the environmental temperature, functional acoustic pressure generator, bubble oscillation frequency, and initial radius. Using methods from dynamical systems theory, including fractal dimension, bifurcation diagrams, time-series analysis, and phase portraits, we analyze the microbubble responses and demonstrate the transition from chaotic to stable oscillations. Multifractal analysis reveals that acoustic pressure, temperature, and initial bubble radius significantly influence bubble dynamics. Higher temperatures result in more energetic oscillations and faster collapse rates. Surface tension is a key factor; higher temperatures reduce surface tension, which can increase bubble stability. The initial radius also impacts stability, with smaller bubbles exhibiting greater stability and larger bubbles being more prone to violent collapses.