Lydersen

class lib.newComponent.lydersen.Lydersen(**kwargs)

Bases: GroupContribution

Group contribution for definition of unknown component using the Lydersen procedure (1955). This method is able to calculate the critical properties.

The resulting instance has all the necessary properties to use in PFD as a predefined compound, using general properties for calculation of other mandatory properties don’t defined by the method.

Parameters:

grouparray

List with group index

contributionfloat

List with group count ocurrences

M: float, optional

Molecular weight, [-]

Tbfloat

Normal boiling temperature, [K]

SG: float, optional

Specific gravity, [-]

Methods

calculo()	Calculation procedure
isCalculable()	Procedure to define the status of input parameter

Notes

M and SG are optional input, anyway know them improve the estimation

Examples

Example 2 in [1] pag 2-342, 2-butanol critical properties

>>> cmp = Lydersen(Tb=372.7, group=[0, 1, 2, 18],
... contribution=[2, 1, 1, 1])
>>> "%0.1f %0.3f" % (cmp.Tc, cmp.Pc.MPa)
'534.5 4.506'
>>> cmp.formula
'C4H10O'

Example in http://en.wikipedia.org/wiki/Lydersen_method, acetone

>>> cmp = Lydersen(Tb=329.25, group=[0, 22], contribution=[2, 1])
>>> "%0.0f" % (cmp.Vc.ccg*cmp.M)
'210'

FirstOrder = 47

isCalculable()

Procedure to define the status of input parameter

calculo()

Calculation procedure

References

[1]

; Perry’s Chemical Engineers’ Handbook 7th Edition, McGraw Hill (1997)

[2]

Lydersen, A. L.; Estimation of Critical Properties of Organic Compounds, Coll. Eng. Univ. Wisconsin, Engineering Experimental Station Rept. 3, Madison, WI (1955)