Abstract
The purpose of the study is to clarify the fluctuation phenomenon of the interface between two immiscible fluids in the rotating cylinders by using the experimental flow visualization and the image analysis. In this system, the inner cylinder can rotate and the outer cylinder is stationary. The cylinders are set coaxial and perpendicular. Both ends of the cylinders are stationary walls. Silicone oil and glycerin solution are used as working fluids. Glycerin solution was dyed with black ink to visualize the interface. The Reynolds number is based on the kinematic viscosity of silicone oil, the rotational speed of the inner cylinder and the length of clearance of the cylinders. When the Reynolds number reaches at a critical number, the interface starts on a fluctuation phenomenon in the neighborhood of the outer cylinder. The digital video camera is used to capture movies of developments of the fluctuation and image analysis is carried out. Amplitudes of the interface are estimated and critical Reynolds numbers of the onset of the fluctuation are determined on several aspect ratios.
