The effect of disordered perturbations on the entropy of an unstable system

Cover Page

Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription Access

Abstract

The contribution of disordered perturbations in density, velocity and pressure to the pair entropy of an unstable system, which sets the direction of its evolution, is estimated. Disordered perturbations arising in the incoming flow due to external influence are calculated by numerical integration of regular equations of multimoment hydrodynamics supplemented with stochastic components. The calculation of the distortion of the pair entropy of the system due to disordered perturbations is performed in the problem of flow around a stationary solid sphere. It is established that disordered perturbations of density, velocity and pressure do not have any noticeable effect on the parameters of the vortex street in the wake behind the sphere.

Full Text

Restricted Access

About the authors

I. V. Lebed

Institute of Applied Mechanics of the Russian Academy of Sciences

Author for correspondence.
Email: lebed-ivl@yandex.ru
Russian Federation, Moscow

References

  1. I.V. Lebed, Russ. J. Phys. Chem. B 8(2), 240 (2014). A.Ph. Kiselev, I.V. Lebed, Chaos Solitons Fractals 142, №110491 (2021).
  2. I.V. Lebed, Russ. J. Phys. Chem. B 18(5), (2024).
  3. I.V. Lebed, Chem. Phys. Rep. 17(1–2), 411 (1998).
  4. I.V. Lebed, The Foundations of Multimoment Hydrodynamics, Part 1: Ideas, Methods andEquations (Nova Science Publishers, N-Y, 2018).
  5. I.V. Lebed, Chem. Phys. Rep. 16(4), 1263 (1997).
  6. A.Ph. Kiselev, I.V. Lebed, Russ. J. Phys. Chem. B 15(1), 189 (2021).
  7. I.V. Lebed, Russ. J. Phys. Chem. B 16(1), 197 (2022)
  8. H. Sakamoto, H. Haniu, J. Fluid Mech. 287, 151 (1995).
  9. L.G. Loitsyanskii, Mechanics of Liquids and Gases (Pergamon, Oxford, 1966).
  10. A.S. Monin, A.M. Yaglom, Statistical Hydromechanics, Part 1 (Nauka, Moscow, 1965)
  11. R. Natarajan and A. Acrivos, J. Fluid Mech. 254, 323 (1993).
  12. K.Hannemann, H. Oertel Jr., J. Fluid Mech. 199, 55 (1989).
  13. H.G. Schuster, Deterministic Chaos (Physik Verlag, Weinheim, 1984).
  14. A.G. Tomboulides and S.A. Orszag, J. Fluid Mech. 416, 45 (2000).
  15. D. Ruelle, F. Takens, Commun. Math. Phys. 20, 167 (1971).
  16. I.V. Lebed, Russ. J. Phys. Chem. B 17(6), 1414 (2023).
  17. A.A. Townsend, The Structure of Turbulent Shear Flow (Cambridge University Press, 1956).
  18. H.K. Moffatt, J. Fluid Mech.. 106, 27 (1981).
  19. I.V. Lebed, S.Y. Umanskii, Russ. J. Phys. Chem. B 1(1), 52 (2007).
  20. J.M. Chomaz, P. Bonneton, E.J. Hopfinger, J. Fluid Mech. 234, 1 (1993).
  21. A. Ph. Kiselev, I.V. Lebed, Russ. J. Phys. Chem. B 15(5), 895 (2021).
  22. I.V. Lebed, Russ. J. Phys. Chem. B 17(5), 1194 (2023).
  23. I.V. Lebed, Russ. J. Phys. Chem. B 16(2), 370 (2022).

Supplementary files

Supplementary Files
Action
1. JATS XML
2. Fig. 1. Time behavior of the paired entropy calculated within the hemispherical concentric layer H0 minus the spatial half-segment; r2 = 2.12, r3= 1.0, Re=400, t*= 6.99.

Download (17KB)
3. Рис. 2. Hemispherical concentric layer H0: 1 ≤ ^r ≤ ^r2, p/2 ≤ q ≤ 0, 2p ≤ j ≤ 0; hemispherical concentric layer H1: 1 ≤ ^r ≤ ^r1, p/2 ≤ q ≤ 0, 2p ≤ j ≤ 0; hemispherical concentric layer H2: ^r1 ≤ ^r ≤ ^r2, p / 2 ≤ q ≤ 0, 2p ≤ j ≤ 0; cos a = 0.886.

Download (21KB)
4. Рис. 3. Введение во временную производственную систему, при Re = 400. Функция =^СП(0(0,2))(т)/=т, рассчитанная по решению Соль 0 в пределах полусферического концентрического слоя н0 за вычетом пространственного полусегмента, представлена кривой 1; ^Р2 = 2.12, ^Р3 = 1.0. Сумма двух функций, ^СП(0(1,2))(т) и ^ИП(1(2,2))(т), представлена кривой 2. Составляющая ^СП(0(1,2))(т) рассчитана по решению Sol0 в пределах полусферического концентрического слоя Н1 ^Р1 = 1.571; составляющая ^ИП(1(2,2))(т) рассчитана по решению Sol1 в пределах области существования решения, расположенной на внешней границе полусферического концентрического слоя Н1. Время перемещения ^t1 = 6,9857, t = (Rea/(2 U0))^t.

Download (21KB)
5. Fig. 4. Time behavior of the inverse pair entropy calculated by Sol0, Re = 400. The function ^S~p*(0(1,)2)(t*), calculated within the hemispherical concentric layer H1, is represented by curve 1; ^r1 =1.571. The function ^S~p*(0(0,)2)(t*), calculated within the hemispherical concentric layer H0 minus the spatial half-segment, is represented by curve 2; ^r2 = 2.12, ^r3 = 1.0. The function ^S~ p*(0(1–,2)2)( t*), calculated within a hemispherical concentric layer with a moving outer boundary ^r1(t), represented by curve 3. Rebuilding time ^t1 = 6.9857, separation time ^t1 = T = 6.99, t * = = (Re a/(2U0))^t *.

Download (27KB)

Copyright (c) 2024 Russian Academy of Sciences