Numerical investigation into the effect of viscosity on bubble dynamics in a narrow channel

In this paper, dynamic behavior of a vapor bubble inside a narrow channel filled with a viscous liquid has been studied numerically. The boundary integral equation method (BIEM) and the procedure of viscous correction of viscous potential flow (VCVPF) have been employed for obtaining the vapor bubble profiles during its pulsations inside the narrow channel filled with a viscous liquid. In the present paper a new method has been proposed for considering the effects of viscosity in a viscous liquid flow in the framework of the Green's integral formula together with the modified form of unsteady Bernoulli equation. The reported experimental and numerical results of the problem under investigation have been used for verification of the results of the present work. Numerical results show that, by increasing the viscosity of liquid around the vapor bubble, the bubble lifetime increases. Numerical results also indicate that for Reynolds numbers with the order of , the viscosity effects are extremely reduced. Furthermore, the dynamic behavior of the bubble in water and oil is investigated at different Reynolds numbers and at different so-called dimensionless channel radii.