How do deformable bubbles modulate turbulence?

In this talk, we will present an experimental study that was designed to answer a specific question: How do finite-sized deformable bubbles modulate their surrounding turbulence? In contrast to previous works on turbulence generated by a swarm of rising bubbles in an otherwise quiescent medium, our study was conducted in an environment with intense background turbulence, which can constantly exchange energy with bubbles through interface deformation. In particular, we utilize a unique experimental setup, named V-ONSET, within which fluid flows, bubble shape, and bubble dynamics are simultaneously measured. We will show how turbulence is modulated in the vicinity of bubbles that undergo strong deformation. The results will pave the foundation for a new regime in turbulent bubbly flows where the pre-existing background turbulence is intense and there is strong two-phase couplings through deformation.