ジャーナル軸受におけるフォトクロミズム可視化手法を用いたマイクロバブル周りの油膜挙動観察

抄録

Microbubbles have attracted attention as a new friction reduction method for journal bearings. Microbubbles are bubbles with a diameter of 100 μm or less, and it has been suggested that they contribute to friction reduction by deforming and rotating in the bearing clearance, but their behavior during operation is still unclear. Therefore, oil film behavior around microbubbles on journal bearings was observed utilizing a photochromism visualization technique that uses an oil film that changes color when irradiated with ultraviolet light as a tracer. As a result, it was confirmed that the microbubbles flowed in the bearing clearance at approximately half the shaft rotation speed while being stretched into an elliptical shape by the shear of the oil film caused by the rotation of the journal. In addition, when focusing on the behavior of the oil film around the microbubbles, a straight flow was observed, which was thought to be caused by the rotation of the microbubble.