# 黏度指數

## 历史

1929年Dean與Davis首創黏度指數的標準[4]，其概念為受評測流體，其100°C↔40°C的黏度變化量，與100°C時同黏度、黏度指數分別為100、0的兩參考流體的100°C↔40°C黏度變化量相比之百分比。最早是以賓州原油煉出的礦物油為VI=100、墨西哥灣原油煉出的礦物油為VI=0[5]早期會用石蠟當作黏度指數為100、0的參考流體[來源請求]

${\displaystyle \log \log(\nu +C)=K-m\cdot \log T}$

Vogel-Cameron則有另一種黏-溫公式如下，同樣有三個特性常數，並以絕對溫度為T

${\displaystyle \eta =A\cdot e^{({\frac {B}{T+C}})}}$

## 黏度指數提昇劑

• 基礎油A，40°C黏度L，100°C黏度H（L > H）
• 基礎油A添加VI提昇劑成為A’，40°C黏度L，100°C黏度H’
• H’>H：（L – H’）<（L – H），表示A’的黏溫穩定性較高

SAE J300的機油黏度規定，SAE 8~60等級的黏度需符合兩項測試規格，以SAE 20為例：

1. 100°C時動力黏度6.9~9.3cSt
2. 150°C、106/s2剪切速率下，絕對黏度>=2.6cP

## 註腳

1. ^ log(log(ν+C))=K-m·log(T), Ubbelohbe-Walter's equation, 1928
2. ^ Lubricants and Lubrication, Section 3.2, Theo Mang,Wilfried Dresel, 2nd Edition, 2007
3. ^ 机械设计. 北京市: 高等教育出版社. 2006年5月: 46–50. ISBN 7-04-019256-X. Authors list列表中的|first1=缺少|last1= (帮助)
4. ^ E.W. Dean, G.H.B Davis, A.D. Bauer and J.H Bergland, “Viscosity Variations of Oils with Temperature”, Chemical and Metallurgical Engineering, Vol.36, P.618, 1929
5. ^ Synthetic Lubricants and High-Performance Functional Fluids, P.403, Chapter 17, Ronald A. Philips, 1st Edition, ISBN 0-8247-0194-1
6. ^ Rheological properties of lubricants, P.102, Jean Briant,Jacques Denis,Guy Parc, 1989
7. ^ Fuels and lubricants handbook: technology, properties, performance, and testing, P.372, George E. Totten, Steven R. Westbrook, Rajesh J. Shah, 2003, ISBN-EB: 978-0-8031-5048-5
8. ^ Fuels and lubricants handbook: technology, properties, performance, and testing, P.372, George E. Totten, Steven R. Westbrook, Rajesh J. Shah, 2003, ISBN-EB: 978-0-8031-5048-5

## 參考文獻

• Mechanics and chemistry in lubricant, Section 4.7~4.8, A. Dorinson, K. C. Ludema, 1985
• Rheological properties of lubricants, Section 4.2~4.3, Jean Briant,Jacques Denis,Guy Parc, 1989
• Engineering tribology, 3rd edition, Section 2.3~2.5, Gwidon W. Stachowiak,Andrew W. Batchelor, 1989
• Lubricants and special fluids, Section 2, Václav Štěpina, Václav Veselý, Václav Veselý, 1992
• Fuels and lubricants handbook: technology, properties, performance, and testing, P.372, George E. Totten, Steven R. Westbrook, Rajesh J. Shah, 2003, ISBN-EB: 978-0-8031-5048-5