Methods

Functions

Approximations

InverseLangevinApproximations.KuhnGrunApproximationType

From Ref. [5]:

\[\mathcal{L}^{-1}(y) \approx 3y + \frac{9}{5}y^3 + \frac{297}{175}y^5 + \frac{1539}{875}y^7 + \frac{126117}{67375}y^9 + \frac{43733439}{21896875}y^{11} + \frac{231321177}{109484375}y^{13} + \frac{20495009043}{9306171875}y^{15} + \frac{1073585186448381}{476522530859375}y^{17} + \frac{4387445039583}{1944989921875}y^{19}\]

source

References

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[2]
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[3]
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[4]
R. Jedynak. New facts concerning the approximation of the inverse Langevin function. Journal of Non-Newtonian Fluid Mechanics 249, 8–25 (2017).
[5]
W. Kuhn and F. Gr{\"u}n. Beziehungen zwischen elastischen Konstanten und Dehnungsdoppelbrechung hochelastischer Stoffe. Kolloid-Zeitschrift 101, 248–271 (1942).
[6]
A. N. Nguessong, T. Beda and F. Peyraut. A new based error approach to approximate the inverse Langevin function. Rheologica Acta 53, 585–591 (2014).
[7]
R. Jedynak. Approximation of the inverse Langevin function revisited. Rheologica Acta 54, 29–39 (2015).
[8]
M. Puso. Mechanistic constitutive models for rubber elasticity and viscoelasticity. Lawrence Livermore National Lab.(LLNL), Livermore, CA (United States) (2003).
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L. R. Treloar. The mechanics of rubber elasticity. Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences 351, 301–330 (1976).
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H. R. Warner Jr. Kinetic theory and rheology of dilute suspensions of finitely extendible dumbbells. Industrial \& Engineering Chemistry Fundamentals 11, 379–387 (1972).