An Approach in Evaluating Adsorbed Layer Thickness for EHL Using Oil-In-Water Emulsions

彈液動潤滑實驗中評估溶水油乳化液吸附層厚度之方法

李榮宗(Rong-Tsong Lee) ； 邱源成(Yuang-Cherng Chiou) ； 陳佑維(Yu-Wei Chen) ； 王聖立(Sheng-Li Wang)

《中國機械工程學刊》 38卷6期 (2017/12) Pp. 613-619

摘要

A mixed-film model with two adsorbed oil layers on the solid surfaces and an emulsion layer between them is proposed. Effects of oil phase concentration, base oil viscosity, emulsifier concentration and pH value on the of the adsorbed oil layer thickness are investigated. Compared with the existing experimental measurements, a simplified formula is proposed to estimate the adsorbed oil layer thickness. Results show that the adsorbed layer thickness increases with increasing oil concentration and viscosity of the base oil, but decreases with increasing pH value and emulsifier concentration because the low pH value and the low emulsifier concentration emulsions make the emulsion unstable, so that it is easy to form the adsorbed oil layer on the solid surfaces. However, effects of oil phase concentration, base oil viscosity, emulsifier concentration and pH value on the adsorbed layer thickness become smaller at higher speed. The base oil type significantly affects the adsorbed layer thickness, and the wetting ability of the synthetic oil of SHF41 is the worst.

關鍵字

Emulsions ； adsorbed layer thickness

並列摘要

本文使用含有吸附油層與乳化液層之混合油膜模型，探討油相濃度、基礎油黏度、乳化劑濃度及其酸鹼值(pH 值)對吸附油層厚度的影響，與現有實驗量測值比較，並提出一簡化公式估算吸附油層厚度。結果顯示吸附油層厚度隨油相濃度和基礎油黏度增加而增加，但隨酸鹼值與乳化劑濃度增加而減少，此乃因為低酸鹼值與低乳化劑濃度乳化液使乳化液不穩定，易在金屬表面形成吸附油層，然而隨轉速增加其對吸附層厚度影響變小。基礎油種類顯著影響吸附油層厚度，合成油SHF41 濕潤能力最差，使得其吸附油層厚度最低。

並列關鍵字

乳化液 ； 吸附油層厚度