Base Oil Viscosity Index Calculator

Calculate Base Oil Viscosity Index (VI)





Formula

The formula to calculate the Viscosity Index (VI) is:

\[ VI = \left(\frac{L - U}{L - H}\right) \times 100 \]

Where:

What is Base Oil Viscosity Index?

The Base Oil Viscosity Index is a measure used to indicate the change in viscosity of lubricating oil with changes in temperature. It is a dimensionless number that represents how much the oil’s viscosity changes as temperature changes. A higher viscosity index indicates a smaller decrease in viscosity with increasing temperature, meaning the oil will maintain its lubricating properties better under high temperatures. This is crucial in applications like engines and machinery where temperature conditions can vary greatly.

Example Calculation

Let's assume the following values:

Using the formula to calculate the Viscosity Index (VI):

\[ VI = \left(\frac{L - U}{L - H}\right) \times 100 = \left(\frac{100 - 20}{100 - 10}\right) \times 100 ≈ 88.89 \]

The Viscosity Index (VI) is approximately 88.89.