Article

Elucidation of the oil film pressure generation mechanism by the dimple pattern

September 2018
The Proceedings of Conference of Hokuriku-Shinetsu Branch 2018.55:I035

DOI:10.1299/jsmehs.2018.55.I035

Authors:

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.

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