Direct numerical simulation of spherical and non-spherical bubble dynamics using the ALPACA compressible multiphase flow solver

Bubbles play a crucial role in various engineering and scientific applications, ranging from sonochemistry and ultrasonic water treatment to medical procedures and cavitation erosion. The simulation of complex bubble dynamics phenomena such as acoustically driven non-spherical oscillations requires both the accurate calculation of inertia and capillary forces. This paper presents a comprehensive study using the ALPACA compressible multiphase flow solver to simulate both spherical and non-spherical bubble dynamics. The study begins with the validation of ALPACA for standard multiphase test cases, including static, dynamic, and capillary waves, demonstrating its ability to avoid spurious currents and to handle surface tension-driven phenomena with adequate resolution. Subsequently, ALPACA is employed to simulate acoustically excited bubbles using a 2D axisymmetric setup. The results reveal that ALPACA can accurately predict spherical dynamics with at least first-order convergence. Furthermore, it is capable of reproducing dominant surface mode oscillations of larger amplitudes. The main novelty of our work is the direct numerical simulation of non-spherical bubble dynamics and the validation of ALPACA against measurement of acoustically driven non-spherical oscillations.     «

Bubbles play a crucial role in various engineering and scientific applications, ranging from sonochemistry and ultrasonic water treatment to medical procedures and cavitation erosion. The simulation of complex bubble dynamics phenomena such as acoustically driven non-spherical oscillations requires both the accurate calculation of inertia and capillary forces. This paper presents a comprehensive study using the ALPACA compressible multiphase flow solver to simulate both spherical and non-spheric...     »

Acknowledgment This research was supported by the EKÖP, Hungary funded by the National Research Development and Innovation Fund under grant number EKÖP-24-3-BME-84. The authors gratefully acknowledge the Gauss Centre for Supercomputing e.V. (www.gauss-centre.eu ) for funding this project by providing computing time on the GCS Supercomputer SuperMUC-NG at Leibniz Supercomputing Centre (www.lrz.de). Project no. TKP-6-6/PALY-2021 has been implemented with the support provided by the Ministry of Culture and Innovation of Hungary from the National Research, Development and Innovation Fund, financed under the TKP2021-NVA funding scheme. The authors acknowledge the financial support of the Hungarian National Research, Development and Innovation Office via NKFIH grant OTKA FK142376.     «

Acknowledgment This research was supported by the EKÖP, Hungary funded by the National Research Development and Innovation Fund under grant number EKÖP-24-3-BME-84. The authors gratefully acknowledge the Gauss Centre for Supercomputing e.V. (www.gauss-centre.eu ) for funding this project by providing computing time on the GCS Supercomputer SuperMUC-NG at Leibniz Supercomputing Centre (www.lrz.de). Project no. TKP-6-6/PALY-2021 has been implemented with the support provided by the Ministry of C...     »