Lattice Boltzmann simulations of bubble interactions on GPU cluster

A three-dimensional two-phase lattice Boltzmann model is adopted to simulate bubble interactions on a multi-graphics processing unit (GPU) cluster. Both the level of the predicted spurious velocity and Laplace's law's satisfaction are used to validate the numerical implementation. The deformation and the terminal velocity of a single-rising bubble are further simulated, and the predicted terminal Reynolds number is contrasted with the available measurement and prediction. Dual-bubble rising at initial in-line and off-line states are also investigated with both uniform and differential bubble radii. For two bubbles of the same size, the trailing bubble suffers a dramatic deformation after entering the wake region generated by the leading bubble. However, this phenomenon is less significant if the larger bubble is placed beneath the smaller bubble. Finally, the present numerical procedure exhibits good scalability for multi-GPU computations.