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Comment: Reverted from v. 53

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LaTeX Math Block
anchorZ_c
alignmentleft
c(p) = \frac{1}{p} - \frac{1}{Z} \frac{dZ}{dp}



LaTeX Math Block
anchorZ_c
alignmentleft
Z(p) = \frac{Z_0}{p_0} \cdot p \cdot \exp \left[ - \int_{p_0}^p c(p) dp  \right]




Expand
titleDerivation


LaTeX Math Block
anchorcg1
alignmentleft
c = - \frac{1}{V} \frac{dV}{dp} = - \frac{d}{dp} \left( \ln V \right) \rightarrow \ln \frac{V}{V_0} = - \int_{p_0}^p c(p) dp 


Substituting

LaTeX Math Inline
bodyV
from
LaTeX Math Block Reference
anchorZ
into
LaTeX Math Block Reference
anchorcg1
one arrives to
LaTeX Math Block Reference
anchorZ_c
.


The
Z-factor value is trending towards unit value (

LaTeX Math Inline
bodyZ \rightarrow 1
) for incompressible fluids and linear pressure dependence (
LaTeX Math Inline
bodyZ \rightarrow a \cdot p
) for strongly compressible Fluids.

Modelling Z-factor 

LaTeX Math Inline
bodyZ(T,p)
as a function of fluidpressure 
LaTeX Math Inline
bodyp
 and temperature 
LaTeX Math Inline
bodyT
 is based on Equation of State.

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