新規表面テクスチャがガスフォイル軸受の潤滑特性に及ぼす影響

抄録

Foil bearing has excellent characteristics such as high damping performance and dimensional changes by installation errors and thermal expansion are acceptable. However, large friction loss problem also occurs in the top foil due to high rotational speed which required to supports shaft without any contact. In this paper, new type of foil bearing which has a surface texture on the top foil was proposed. Then the effect of the texture was verified by the rotational motion experiment under high circumferential speed and dry lubrication. In the case of bearing with dimples on the contact area, the effect of friction reduction was confirmed during boundary lubrication as in wet lubrication. On the other hand, it was also confirmed that the dimples adversely affect the air film formation as the sliding speed increase. In the case of newly designed Fibonacci-groove (F-groove) model, early transition from boundary lubrication to fluid lubrication was realized while the friction coefficient is increasing at boundary lubrication. In addition, high friction reduction effect was confirmed under the maximum sliding speed. Furthermore, additional friction reduction effect and suppression effect of temperature increasing were obtained by combining the specific textures.