In the absence of any laboratory data, correlations exist that relate viscosity and temperature, given the oil gravity. The following equation relating viscosity, gravity, and temperature was developed by Beggs and Robinson after observing 460 oil systems: The data set from which this relationship was obtained included a range of between 16° and 58° API […]

Read More…# Category: Fluid Properties – Basic Principles

## Fluid Properties Viscosity #1

This property of a fluid indicates its resistance to flow. It is a dynamic property, in that it can be measured only when the fluid is in motion. Viscosity, therefore, is simply the ratio at any shear rate of the shear stress to the shear rate. There are two expressions of viscosity, absolute (or dynamic) […]

Read More…## Specific Gravity and Density

Specific gravity of a liquid is the ratio of the density of the liquid at 60°F to the density of pure water. API gravity is related to the specific gravity by the following equation: The specific gravity of a gas is the ratio of the density of the gas to the density of air at […]

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