Abstract
The D3Q19 multi relaxation time (MRT) lattice Boltzmann model is adopted to simulate the instability phenomenon within a three-dimensional cavity at various depth-width aspect ratios ranging from 1 to 3. The computations are conducted on a single node multi graphic processing unit (GPU) system, consisting of three nVIDIA M2070 devices using OpenMP. Results show that transition takes place between 1750<Re <sub>cr</sub> <1950, for cubic cavity and 1100<Re <sub>cr</sub> <1450, for deep cavity flows with aspect ratio 2 and 3. This indicates that an increase of the depth-width aspect ratio would induce the transition at lower Reynolds number and is consistent with the previous results for two-dimensional cavities, though the critical Reynolds number is approximately 75% lower for three dimensional cavity. © 2013 Elsevier Ltd.