Tomomi HONDA’s research while affiliated with University of Fukui and other places

It is required to reduce the friction loss of the sliding parts in order to improve fuel economy of the internal combustion engine. It has the effect of supplying the lubricating oil to the sliding surface, and its effect varies depending on the dimple pattern. However, the mechanism of oil film pressure generation has not been elucidated. The purpose of this study is to elucidate of it by the dimple pattern. We analyzed maximum load carrying capacity and fluid pressure by the dimples using the TED/CPA. As a result, maximum load carrying capacity increased with increasing the dimple diameter, and maximum load carrying capacity decreased with increasing the depth. There is an appropriate curve degree dependance on the depth of dimple. Maximum load carrying capacity increased and it per one dimple decreased as the number of dimple increased.

Dimple improves supplying the lubricating oil and it reduces friction of the sliding surface. its effect varies depending on the dimple shape and arrangement pattern, therefor generic design method of dimples has not been clarified. The purpose of this study is proposing design method of dimples based on fluid pressure under fluid lubrication. We analyzed maximum load carrying capacity and fluid pressure using the TED/CPA when single and multiple dimples were applied load and sliding velocity in oil lubrication. We changed diameter of dimple, depth, curve, number of dimples and pitch between dimples. In case of single dimple, maximum load carrying capacity increases with increasing the dimple diameter, and maximum load carrying capacity decreases with increasing the depth. There is an appropriate curve degree dependance on the depth of dimple. In case of multiple dimples, the effect of dimple overlapped and fluid pressure mutually increases. Maximum load carrying capacity increases and it per one dimple decreases as the number of dimple increases. Maximum load carrying capacity decreases with extending pitch between dimples. As a result, we proposed the method to investigate the influence of dimple shape on maximum load carrying capacity and fluid pressure.