Measuring characteristics of gas bubbles in a fluid is among important and challenging tasks in many industrial settings. Such measurements can be carried out more efficiently and accurately by using a Wave Phase Conjugation (WPC) device due to its useful relevant properties such as signal retro-focusing and compensation for phase distortions. In the present work, this technique is explored via numerical modelling in application to bubble size measurements. A modified version of the high-order Nodal Discontinuous Galerkin (NDG) method, which is based on the non-collocated solution and flux bases, is implemented for modelling of the acoustic wave propagation in the WPC conjugator and the surrounding fluid. Additional volume-averaged terms are added to the model to account for the presence of bubbles in the fluid. The modified Keller-Miksis model is employed to simulate vibrations of bubbles exposed to acoustic waves. After the verification and validation of the numerical model, the interaction of bubble dynamics with the WPC process is examined. The results demonstrate that the WPC-based technique is an adequate tool to be used for measuring bubble dimensions via stimulation of the bubble natural frequency.
