Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 2
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

Nonlinear excitation of the entropy perturbations by magnetosonic waves in a uniform and infinite plasma model is considered. The wave vector of slow or fast mode forms an arbitrary angle θ (0≤θ≤π) with the equilibrium straight magnetic field, and all perturbations are functions of the time and longitudinal coordinate. Thermal conduction is the only factor which destroys isentropicity of wave perturbations and causes the nonlinear excitation of the entropy mode. A dynamic equation is derived which describes excitation of perturbation in the entropy mode in the field of dominant magnetosonic mode. Effects associatiated with temperature dependent and anisotropic thermal conduction are considered and discussed.
Go to article

Bibliography

1. Afanasyev A.N., Nakariakov V.M. (2014), Nonlinear slow magnetoacoustic waves in coronal plasma structures, Astronomy and Astrophysics, 573: A32, doi: 10.1051/0004-6361/201424516.
2. Ballai I. (2006), Nonlinear waves in solar plasmas – a review, Journal of Physics: Conference Series, 44(20): 20–29, doi: 10.1088/1742-6596/44/1/003.
3. Braginskii S.I. (1965), Transport processes in plasma, Reviews of Plasma Physics, M.A. Leontovich [Ed.], Vol. 1, p. 205, Consultants Bureau, New York.
4. Callen J.D. (2003), Fundamentals of Plasma Physics, Lecture Notes, University of Wisconsin, Madison.
5. Chin R., Verwichte E., Rowlands G., Nakariakov V.M. (2010), Self-organization of magnetoacoustic waves in a thermal unstable environment, Physics of Plasmas, 17(32): 107–118, doi: 10.1063/1.3314721.
6. Dahlburg R.B., Mariska J.T. (1988), Influence of heating rate on the condensational instability, Solar Physics, 117(1): 51–56, doi: 10.1007/BF00148571.
7. Field G.B. (1965), Thermal instability, The Astrophysical Journal, 142: 531–567, doi: 10.1086/148317.
8. Heyvaerts J. (1974), The thermal instability in a magnetohydrodynamic medium, Astronomy and Astrophysics, 37(1): 65–73.
9. Hollweg J.V. (1985), Viscosity in a magnetized plasma: Physical interpretation, Journal of Geophysical Research, 90(A8): 7620–7622, doi: 10.1029/JA090iA08p07620.
10. Ibáñez S.M.H., Parravano A. (1994), On the thermal structure and stability of configurations with heat diffusion and a gain-loss function. 3: Molecular gas, The Astrophysical Journal, 424(2): 763–771, doi: 10.1086/173929.
11. Krall N.A., Trivelpiece A.W. (1973), Principles of Plasma Physics, McGraw Hill, New York.
12. Kumar N., Kumar P., Singh S. (2006), Coronal heating by MHD waves, Astronomy and Astrophysics, 453: 1067–1078, doi: 10.1051/0004-6361:20054141.
13. Leble S., Perelomova A. (2018), The Dynamical Projectors Method: Hydro and Electrodynamics, CRC Press.
14. De Moortel I., Hood A.W. (2004), The damping of slow MHD waves in solar coronal magnetic fields, Astronomy and Astrophysics, 415: 705–715, doi: 10.1051/0004-6361:20034233.
15. Nakariakov V.M., Mendoza-Briceño C.A., Ibáñez M.H. (2000), Magnetoacoustic waves of small amplitude in optically thin quasi-isentropic plasmas, The Astrophysical Journal, 528(2, Part 1): 767–775, doi: 10.1086/308195.
16. Ofman L., Wang T. (2002), Hot coronal loop oscillations observed by SUMER: slow magnetosonic wave damping by thermal conduction, The Astrophysical Journal, 580(1): L85–L88, doi: 10.1086/345548.
17. Parker E.N. (1953), Instability of thermal fields, The Astrophysical Journal, 117: 431–436, doi: 10.1086/145707.
18. Perelomova A. (2006), Development of linear projecting in studies of non-linear flow. Acoustic heating induced by non-periodic sound, Physics Letters A, 357: 42–47, doi: 10.1016/j.physleta.2006.04.014.
19. Perelomova A. (2008), Modelling of acoustic heating induced by different types of sound, Archives of Acoustics, 33(2): 151–160.
20. Perelomova A. (2018a), Magnetoacoustic heating in a quasi-isentropic magnetic gas, Physics of Plasmas, 25: 042116, doi: 10.1063/1.5025030.
21. Perelomova A. (2018b), Magnetoacoustic heating in nonisentropic plasma caused by different kinds of heating-cooling function, Advances in Mathematical Physics, 2018: Article ID 8253210, 12 pages, doi: 10.1155/2018/8253210.
22. Perelomova A. (2020), Hysteresis curves for some periodic and aperiodic perturbations in magnetosonic flow, Physics of Plasmas, 27(10): 102101, doi: 10.1063/5.0015944.
23. Ruderman M.S., Verwichte E., Erdélyi R., Goossens M. (1996), Dissipative instability of the MHD tangential discontinuity in magnetized plasmas with an isotropic viscosity and thermal conductivity, Journal of Plasma Physics, 56(2): 285–306, doi: 10.1017/S0022377800019279.
24. Sabri S., Poedts S., Ebadi H. (2019), Plasma heating by magnetoacoustic wave propagation in the vicinity of a 2.5D magnetic null-point, Astronomy and Astrophysics, 623, doi: 10.1051/0004-6361/201834286.
25. Soler R., Ballester J.L., Parenti S. (2012), Stability of thermal modes in cool prominence plasmas, Astronomy and Astrophysics, 540: A7, doi: 10.1051/0004-6361/201118492.
26. Spitzer L. (1962), Physics of Fully Ionized Gases, 2nd ed., New York, Interscience.
27. Vesecky J.F., Antiochos S.K., Underwood J.H. (1979), Numerical modeling of quasi-static coronal loops. I – Uniform energy input, The Astrophysical Journal, 233(3): 987–997, doi: 10.1086/157462.
28. Wang T. (2011), Standing slow-mode waves in hot coronal loops: observations, modeling, and coronal seismology, Space Science Reviews, 158: 397–419, doi: 10.1007/s11214-010-9716-1.
29. Zavershinskii D.I., Molevich N.E., Riashchikov D.S., Belov S.A. (2020), Nonlinear magnetoacoustic waves in plasma with isentropic thermal instability, Physical Review E, 101(4): 043204, doi: 10.1103/PhysRevE.101.043204.
Go to article

Authors and Affiliations

Anna Perelomova
1

  1. Gdansk University of Technology, Faculty of Applied Physics and Mathematics, Gdansk, Poland
Download PDF Download RIS Download Bibtex

Abstract

Kidney Cooling Jacket (KCJ) preserves the kidney graft, wrapped in the jacket, against the too fast time of temperature rise during the operation of connecting a cooled transplant to the patient’s bloodstream. The efficiency of KCJ depends on the stationarity of the fluid flow and its spatial uniformity. In this paper, the fluid velocity field inside the three different KCJ prototypes has been measured using the 20 MHz ultrasonic Doppler flowmeter. The simplified 2D geometrical model of the prototypes has been presented using COMSOL Multiphysics to simulate the fluid flow assuming the laminar flow model. By comparing the numerical results with experimental data, the simplified 2D model is shown to be accurate enough to predict the flow distribution of the internal fluid velocity field within the KCJ. The discrepancy between the average velocity measured using the 20 MHz Doppler and numerical results was mainly related to the sensitivity of the velocity measurements to a change of the direction of the local fluid flow stream. Flux direction and average velocity were additionally confirmed by using commercial colour Doppler imaging scanner. The current approach showed nearly 90% agreement of the experimental results and numerical simulations. It was important for justifying the use of numerical modelling in designing the baffles distribution (internal walls in the flow space) for obtaining the most spatially uniform field of flow velocity.
Go to article

Authors and Affiliations

Barbara Gambin
1
ORCID: ORCID
Ilona Korczak-Cegielska
2
Wojciech Secomski
1
Eleonora Kruglenko
1
Andrzej Nowicki
1

  1. Department of Ultrasound, Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
  2. Doctoral Studies of Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland

This page uses 'cookies'. Learn more