Measurements of Water-Air Flow Phenomena in a Chamber with a Rotating Shaft

Abstract

AbstractThe paper concerns the phenomena of the fluid film that occurs in the bearing chamber of an aircraft engine. The geometry of the system includes two concentric cylinders, between which there is a mixture of oil and air. The fluid circulates in a closed circuit. The rotary movement of the inner cylinder causes creation of the fluid film on the walls of the chamber. The article proposes a measurement method that is allowing observation of this fluid film and, in particular, analysis of the movement of the air bubbles occurring in the film. An own model of the bearing chamber with transparent walls was constructed for the research. For the investigation, water was used instead of oil. Observation of the behaviour of the flow was possible thanks to video recordings made with the use of a fast-capture camera. The results presented in the paper include velocity magnitudes of the air bubbles in the fluid film in dependence on the rotational speed of the shaft and water volume fraction and with a range from 0.37 to 0.91 m/s. The results presented in this article can be used for the bearing chamber numerical models validation.