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Consequently, if a liquid has dynamic viscosity of n centiPoise, and its density is not too different from that of water, then its kinematic viscosity is around n centiStokes. For gas, the dynamic viscosity is usually in the range of 10 to 20 microPascal-seconds, or 0.01 to 0.02 centiPoise. The density is usually on the order of 0.5 to 5 kg/m^3.
Viscosity is a measure of a fluid's rate-dependent resistance to a change in shape or to movement of its neighboring portions relative to one another. [1] For liquids, it corresponds to the informal concept of thickness; for example, syrup has a higher viscosity than water. [2]
A heavy liquid is a solution or liquid chemical substance with a high density and a relatively low viscosity. Heavy liquids are often used for determination of density in mineralogy, for density gradient centrifugation and for separating mixtures. A bottle of bromoform, a heavy liquid
The viscosity of a shear thickening – i.e. dilatant – fluid appears to increase when the shear rate increases. Corn starch suspended in water ("oobleck", see below) is a common example: when stirred slowly it looks milky, when stirred vigorously it feels like a very viscous liquid.
At low shear rates, the shear is too low to be impeded by entanglements and the viscosity value of the system is η 0, or the zero shear rate viscosity. The value of η ∞ represents the lowest viscosity attainable and may be orders of magnitude lower than η 0 , depending on the degree of shear thinning.
Examples of Newtonian liquids include water, glycerin, motor oil, honey, or mercury. A non-Newtonian liquid is one where the viscosity is not independent of these factors and either thickens (increases in viscosity) or thins (decreases in viscosity) under shear. Examples of non-Newtonian liquids include ketchup, custard, or starch solutions. [37]
MÄnuka honey is an example of a thixotropic material.. Thixotropy is a time-dependent shear thinning property. Certain gels or fluids that are thick or viscous under static conditions will flow (become thinner, less viscous) over time when shaken, agitated, shear-stressed, or otherwise stressed (time-dependent viscosity).
The clear cut definition of light and heavy crude varies because the classification is based more on practical grounds than theoretical. The New York Mercantile Exchange (NYMEX) defines light crude oil for domestic U.S. oil as having an API gravity between 37° API (840 kg/m 3) and 42° API (816 kg/m 3), while it defines light crude oil for non-U.S. oil as being between 32° API (865 kg/m 3 ...