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ali
05-12-2008, 11:53 AM
how i can Calculating the viscosity blending index of a liquid consisting of two
or more liquids having different viscosities

01-15-2009, 11:42 AM
Bro Ali,
You can get it by applying mixing rule which is you need to the viscosity of pure component fraction and sum all those to get the mixture viscosity. Anyone please comment if there is any mistakes.

AbuFaisal
03-05-2009, 02:11 PM

Viscosity of Liquids | Complore - Study Prepare ***** CAT ()

kuttybalu
03-12-2009, 09:27 AM
Viscosity blending equations
Calculating the viscosity blending index of a liquid consisting of two or more liquids having different viscosities is a two step procedure. The first step involves calculation of the Viscosity Blending Index (VBI) of each component of the blend using the following equation (known as a Refutas equation):

(1) VBI = 14.534 × ln[ln(v + 0.8)] + 10.975

where v is the viscosity in centistokes and ln is the natural logarithm (Loge).

The second step involves using this equation:

(2) VBIBlend = [wA × VBIA] + [wB × VBIB] + ... + [wX × VBIX]

where w is the weight fraction (i.e., % ÷ 100) of each component of the blend. In using the above blending equation, it is necessary that all viscosities are determined at the same temperature, for example, 100 oC.

(Reference: Robert E. Maples (2000), Petroleum Refinery Process Economics, 2nd Edition, Pennwell Books, ISBN 0-87814-779-9)

Once the viscosity blending number of a blend is obtained with equation (2), the viscosity of the blend can be determined by using the invert of equation (1):

(3) v = ee(VBN - 10.975) ÷ 14.534 - 0.8

where VBN is the viscosity blending number of the blend and e is the transcendental number 2.71828, also known as Euler's number.
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npm1975
10-30-2009, 03:07 PM
Hi, this algorith is very useful but it turns complicated when you try to get a mixture of 3 o more components having final viscosity looking for components fraction.

There is a software from Astroninc (). Does anybody have a link to download a full version of Petrochem Toolkit software or similar to do that type of calculaions? example:

Estimate the volume fractions of four components to make a 380 cSt fueloil by using 5, 600, 150 and 400 cSt compounds

thiafis
11-04-2009, 04:19 PM
how i can Calculating the viscosity of mixture ethylene ,oxygen and nitrogen ??? with the above type ?? thanks