Viscous M女ous Intermediate Mobile Mobile Shear rate Shear rate y Liquid or gas Approx viscosity in Pas Hydrogen 105 Air 2x103 Petrol 3x10 Water 10 Lubricating oil 101 Glycerol 10e.1) Com syrup Bitumen Approximate viscosities of some common ewtonian fluids. the viscosity of the solvent or continuous phase.Pa.s dimensionless relative viscosity,n which is the ratio of the viscosity of a suspension to its continuous phase viscosity.n/n: the dimensionless specific viscosity,n,given byn-1: ·the intrinsic viscosity.【nl(with dime )which is the specific ity divided by the dis the kinematic viscosity,pwhich in pre e(你-1/c: centi-Stokes,c5,for thin liquids,with water at 20C-1 cS. The effect of temperature on viscosity The most widely-used expression is that due to Andrade logis n =A+B/T where T is the temperature in degrees absolute (C+273.15).i.e.K.Note that this equation is also known by other names for instance the Arrhenius law where B is replaced by E/R where E is an activation energy for viscous flow and R is the universal gas constant.The activation energy E is said to be a measure of the height of a potential energy barrier associated with the force needed to produce elemental quantum steps in the movement of molecules. Arrhenius =4eh) 55 The effect of temperature on viscosity Arrhenius η = A exp −Ea RT ⎛ ⎝ ⎜ ⎞ ⎠ ⎟