Table of Contents
What is the significance of viscosity index?
The viscosity index (VI) is an arbitrary, unit-less measure of a fluid’s change in viscosity relative to temperature change. It is mostly used to characterize the viscosity-temperature behavior of lubricating oils. The lower the VI, the more the viscosity is affected by changes in temperature.
How viscosity and viscosity index is determined what is its significance?
It is the most important property which determines the performance of lubricating oils under operating conditions. Viscosity index used to characterize the viscosity-temperature behaviour of lubricating oils. The lower the Viscosity index, the more the viscosity is affected by changes in temperature.
Why the determination of viscosity is important for the fuel and lubricating oils used in IC engines?
Viscosity is a measure of an oil’s resistance to flow. The benefits of oils with a higher VI are: A general increase in viscosity at higher temperatures, which results in lower oil consumption and less wear. A reduced viscosity at lower temperatures, which will improve starting and lower fuel consumption.
What is viscosity index lubrication?
The viscosity index (VI) of a lubricant is the rate of the viscosity change due to a temperature change. To know if a lubricant meets the asset’s requirements based on the operating temperature range, you must understand the VI.
What is viscosity in lubricants?
Viscosity is a measure of the internal friction of a fluid. It is the most important physical property of a fluid in the context of lubrication. The viscosity of a lubricant varies with temperature and pressure and, in some cases, with the rate at which it is sheared.
What is viscosity index in chemistry?
Definition. Viscosity Index (VI) is an empirical measure of how much the viscosity of a lubricating oil changes with a change in temperature; the viscosity of higher VI oils change less with a unit change in temperature.
What is the significance of cloud and pour point?
The Pour Point Tells The Temperature Below Which Oil Cannot Be Used As Lubricant. Cloud Point Indicates The Tendency Of Oil To Plug Filters Or Small Orifices At Cold Operating Temperature. So, Cloud And Pour Point Also Tells Us The Suitability Of Lubricating Oils In Cold Condition.
Why is viscosity important in making fuel?
Viscosity is one of the most important factors which directly affects combustion quality. Controlling the viscosity of fuel oil is an important aspect of an efficient combustion. High viscosity fuel prevents correct atomisation,which takes place in the fuel injectors.
Why is viscosity important in fluid mechanics?
The viscosity is an intensive property of a fluid that measures its internal resistance to motion or deformation. It plays an important role in areas such as aerodynamics and reservoir engineering since it determines the nature of the flow of a given fluid, such as air, water or oil.
What is the effect of temperature on viscosity Mcq?
The correct answer is Decreases with an increase in temperature. The viscosity of liquids decreases with an increase in temperature while it increases in the case of gases. Viscosity is a measure of resistance to flow which arises due to the internal friction between layers of fluid.