Research Article | | Peer-Reviewed

The Increasing of the Heat Transfer Coefficient of Short Linear Heat Pipes

Received: 3 October 2023    Accepted: 24 October 2023    Published: 17 November 2023
Views:       Downloads:
Abstract

The results of the experimental studies of heat transfer coefficients KHP of short linear heat pipes (HP’s) with a Laval nozzle-liked vapour channel, and with a partially swirled vapour flow inside the channel are presented. A partial azimuthal swirling of the jet vapour stream is created using inclined injection channels 1 mm in diameter in a flat multilayer mech evaporator, with an inclination angle φ relative to the longitudinal axis in the azimuthal direction, in the range of 0° < φ < 60°. The heat transfer coefficients KHP of a set of the identical HP’s with a different inclination angles φ of the injection channels in the evaporators, with the same working fluid mass filling (δm/m ≤ 0.1 %), at the same evaporator temperature heat load δT = Tev –TB = (20 ± 0.03) K, represent an extreme convex function, depending on the inclination angle φ magnitude of the injection channels, with a maximum at the swirled angle of the vapour flow φ = 26° ± 2°. The magnitude of the excess of the KHP with a swirling vapour flow over the identical HP’s with a direct vapour flow reaches 10%. An analysis of the recommended vapour channel shape, carried out by the estimating of the Richardson number Ri of the vapour flow jets above the evaporator, allowed us to estimate the value of the dimensionless longitudinal radius of curvature δ/Rconf of the confuser part of the vapour channel, which is determined from the condition of minimal friction losses during the flow of moist vapour in the boundary layer δ along the concave wall of the confuser part of the vapour channel with a longitudinal radius of curvature Rconf. The concave diffuser part shape of the vapour channel is determined by the condition that the moving vapour jets velocity vectors must be parallel to the longitudinal axis of the diffuser part of the HP’s vapour channel. The results of the numerical simulation of the hydraulic resistance coefficients ξvp of the HP’s vapour channel, closed with flat covers, with partially swirling jet vapour flow, obtained by using the ANSYS FLUENT program, show a decrease in ξvp coefficients at high values of the evaporator temperature load, in the range of vapour flow velocities 1 m/s < uz ≤ 100 m /s, and in the range of swirling angles 0°<φ<30°. With the increasing the swirling angles φ>30°, a sharp increase in the hydraulic resistance coefficient ξvp begins.

Published in American Journal of Modern Physics (Volume 12, Issue 3)
DOI 10.11648/j.ajmp.20231203.11
Page(s) 30-46
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Short Linear HP’s, Azimuthal Swirling of the Vapour Jets, Hydraulic Resistance Coefficient

References
[1] Gerasimov Yu. F., Maidanik Yu. F., Shchegolev G. T., Filippov G. A., Starikov L. G., Kiseev V. M., Dolgirev Yu. E. Low-temperature heat pipes with separate channels for vapour and liquid. // Engineering Physics Journal, 1975, v. 28, N. 6, pp. 957-960.
[2] Tong B. Y., Wong T. N., Ooi K. T. Closed-loop pulsating heat pipe// Applied Thermal Engineering, 2001, v. 21, № 18, pp. 1845-1862.
[3] Akachi H. Structure of Heat Pipe. US patent 4921041. 1990.
[4] Seryakov A. V. Intensification of heat transfer processes in the low temperature short heat pipes with Laval nozzle formed vapour channel //American Journal of Modern Physics 2018, v. 7, № 1, pp. 48-61.
[5] Seryakov A. V. Сomputer modeling of the vapour vortex orientation changes in the short low temperature heat pipes //International Journal of Heat and Mass Transfer 2019 v. 140. pp. 243-259.
[6] Seryakov A. V. Resonant vibration heat transfer coefficient increase of short low-temperature heat pipes //International Journal of Heat and Mass Transfer 2020. v. 158. pp. 1-22. Article 119764.
[7] Goldstick M. A. Vortex flow. - Novosibirsk: Nauka, 1981. - 336 p.
[8] Alekseenko S. V., Kuibin P. A., Okulov V. L. Introduction to the theory of concentrated vortices. Novosibirsk: Institute of Thermophysics 2003, 504 p.
[9] Khalatov A. A. Theory and practice of swirling flows. Kiev: Naukova Dumka 1989. 192 p.
[10] Gupta A., Lilly D., Sayred N. Swirled Flows. Moscow: Mir, 1987. 588 p.
[11] Shchukin V. K. Heat exchange and hydrodynamics of internal flows in the fields of mass forces. -M.: Mashinostroenie, 1980. – 240 p.
[12] Shchukin V. K., Khalatov A. A. Heat transfer, mass transfer and hydrodynamics of twisted flows in axisymmetric channels. - M.: Mashinostroenie, 1982. -200 p.
[13] Kholodkova O. Yu., Fafurin A. V. Experimental study of heat transfer in a cylindrical channel in the presence of initial swirling and blowing of various gases. - In the book Heat and Mass Exchange in Aircraft Engines. Proceedings of KAI. Kazan, 1974, v. 178, pp. 20-27.
[14] Loytsyansky L. G. Mechanics of liquid and gas. 7th ed. - M: 2003. – 840 p.
[15] Landau L. D., Lifshits E. M. Theoretical Physics in 10 volumes. Volume 6. Hydrodynamics. -M: Nauka, 1986. – 736 p.
[16] Seryakov A. V. The solving of the inverse thermal conductivity problem for study the short linear heat pipes // Engineering 2022, v. 14, pp. 1-32.
[17] Seryakov A. V., Alekseev A. P. Solution of the Inverse Problem of Heat Conduction for Investigation of Short Linear Heat Tubes// Vestnik of the International Academy of Refrigeration 2022 №1. pp. 83-97.
[18] Kutateladze S. S., Leontiev A. I. Heat and Mass Exchange and Friction in Turbulent Boundary Layer. M.: Energia. 1972. 376с.
[19] Prandtl L. Gesamelte Abhandlungen. Berlin u. a. Springer-Verlag, 1961, Bd. 2, pp. 798-811.
[20] Bradshaw P. The analogy between streamline curvature and buoyancy in turbulent shear flow. Journal of Fluid Mechanics 1969. v. 36, pt. 1, pp. 177-191.
[21] Kutateladze S. S., Volchkov E. P., Terekhov V. I. Aerodynamics and Heat and Mass Transfer in Limited Vortex Flows. Novosibirsk: IT SB AN USSR. 1987, 282 p.
[22] Gostintsev Yu. A. Heat and mass transfer and hydraulic resistance in the course of a rotating liquid flow through a pipe// Izvestiya AN USSR Mekhanika Zhidkosti i Gaza. 1968, № 5, pp. 115-119.
[23] Migai V. K., Golubev L. K. Friction and Heat Exchange in a Turbulent Swirled Flow with Variable Torsion in a Pipe// Izvestiya AN USSR Energetika i Transport. 1969, No. 4, pp. 141-145.
[24] Seryakov A. V., Alekseev A. P. A Study of the Short Heat Pipes by the Monotonic Heating Method. 2020// Journal of Physics: Conference Series 1683 022051.
[25] Corino E. R., Brodkey R. S. A visual investigation of the wall region in turbulent flow// Journal of Fluid Mechanics 1969, v. 37, № 1, pp. 1-30.
[26] Shchukin, A. V. Turbulent boundary layer on a curvilinear surface (in Russian) // Izvestiya Vuzov. Aviation Engineering. 1978, № 3, pp. 113-120.
[27] Ustimenko, B. P. Turbulent transfer processes in rotating flows. Alma-Ata: Nauka. 1977. 228 p.
[28] Gillis J. C., Johnston J. P., Kays W. M., Moffat R. J. Turbulent boundary layer on a convex, curved surface: Report NHMT-31. Stanford University 1980. 295p.
[29] Bradshaw P. Review. Complex turbulent flows. Transactions ASME. Ser. I, 1975, v. 97, № 2, pp. 146-154.
[30] Wattendorf F. H. A study of effect of curvature on fully developed flow. Proceedings of the Royal Society, London. Ser. A. 1935, v. 148, pp. 565-597.
[31] Mayle R. E., Blair M. E., Kopper F. C. Turbulent boundary layer heat transfer on curved surfaces. Transactions ASME, Journal of Heat transfer 1979. v. 101, № 3, pp. 521-525.
[32] Vasiliev, A. P.; Kudryavtsev, V. M.; Kuznetsov, V. A. et al. Fundamentals of Theory and Calculation of Liquid Rocket Engines. In 2 books. -M: Vyshaya shkola 3rd ed., 1993. Book 1 - 383 p. Book 2 - 368 p.
[33] Brassard D., Ferchichi M. Transformation of polynomial for a contraction wall profile // Journal of Fluids Engineering v. 127. pp. // pp. 183-185. 2005.
[34] Kurokava J., Kajigaya A., Matusi J., Imamura H. Supression of swirl in a conical diffuser by use of J-groove, in: Proc. 20th IAHR Symposium on hydraulic machinery and systems. Charlotte, North Carolina, USA, DY-01. 2000.
[35] Doolan C. J. Numerical evaluation of contemporary low-speed wind tunnel contraction designs // Journal of Fluids Engineering v. 129. pp. 1241-1244. 2007.
[36] CFdesign 10.0 2009. Version 10.0 – 20090623. User’s Guide.
[37] Fluent User’s Manual, Version 6.0. November 2001.
[38] Kochin N. E., Kibel I. A., Roze N. V. Theoretical Hydromechanics. Part 1. 6th ed. - М: 1963. -584 p.
[39] Akhmetov V. K., Shkadov V. Ya. Numerical modeling of viscous vortex flows for technical applications. MSCU. Moscow 2009. 176 p.
[40] Akhmetov, V. K.; Shkadov, V. Ya. To a question about stability of a free vortex (in Russian) // Vestnik of Moscow State University. Series 1. Mathematics and Mechanics 1987. №2 pp. 35-40.
[41] Akhmetov V. K., Shkadov V. Ya. Development and stability of swirling currents // Izvestia AS USSR. Fluid and Gas Mechanics 1988. №4, pp. 3-11.
[42] GOST RF 34437-2018 Pipeline valves. Methods of experimental determination of hydraulic and cavitation characteristics.
[43] RD RF 26-07-32-99. Pipeline valves.
[44] B a t c h e l o r G. К. Axial flow in a trailing vortices//Journal of Fluid Mechanics 1964. 20, N 4. pp. 645-658.
[45] Faghri A. Heat Pipe Science and Technology. Washington USA, Taylor and Francis. 1995. p. 874.
[46] Bernard Robert. – A McCormack scheme for incompressible flow. – Computers & Mathematics with Applications. 1992. v. 24. No. 5/6. – pp. 151-168.
[47] Hoffman J. D. Numerical methods for engineers and scientists. Second edition revised and expanded. – New York. Marcel Dekker, Inc. – 2001. – 825 p.
[48] Bronstein I. N., Semendyaev K. A. Handbook of Mathematics. - M.: Nauka, 1980. - 976 p.
Cite This Article
  • APA Style

    Vladimirovich, S. A. (2023). The Increasing of the Heat Transfer Coefficient of Short Linear Heat Pipes. American Journal of Modern Physics, 12(3), 30-46. https://doi.org/10.11648/j.ajmp.20231203.11

    Copy | Download

    ACS Style

    Vladimirovich, S. A. The Increasing of the Heat Transfer Coefficient of Short Linear Heat Pipes. Am. J. Mod. Phys. 2023, 12(3), 30-46. doi: 10.11648/j.ajmp.20231203.11

    Copy | Download

    AMA Style

    Vladimirovich SA. The Increasing of the Heat Transfer Coefficient of Short Linear Heat Pipes. Am J Mod Phys. 2023;12(3):30-46. doi: 10.11648/j.ajmp.20231203.11

    Copy | Download

  • @article{10.11648/j.ajmp.20231203.11,
      author = {Seryakov Arkady Vladimirovich},
      title = {The Increasing of the Heat Transfer Coefficient of Short Linear Heat Pipes},
      journal = {American Journal of Modern Physics},
      volume = {12},
      number = {3},
      pages = {30-46},
      doi = {10.11648/j.ajmp.20231203.11},
      url = {https://doi.org/10.11648/j.ajmp.20231203.11},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajmp.20231203.11},
      abstract = {The results of the experimental studies of heat transfer coefficients KHP of short linear heat pipes (HP’s) with a Laval nozzle-liked vapour channel, and with a partially swirled vapour flow inside the channel are presented. A partial azimuthal swirling of the jet vapour stream is created using inclined injection channels 1 mm in diameter in a flat multilayer mech evaporator, with an inclination angle φ relative to the longitudinal axis in the azimuthal direction, in the range of 0° HP of a set of the identical HP’s with a different inclination angles φ of the injection channels in the evaporators, with the same working fluid mass filling (δm/m ≤ 0.1 %), at the same evaporator temperature heat load δT = Tev –TB = (20 ± 0.03) K, represent an extreme convex function, depending on the inclination angle φ magnitude of the injection channels, with a maximum at the swirled angle of the vapour flow φ = 26° ± 2°. The magnitude of the excess of the KHP with a swirling vapour flow over the identical HP’s with a direct vapour flow reaches 10%. An analysis of the recommended vapour channel shape, carried out by the estimating of the Richardson number Ri of the vapour flow jets above the evaporator, allowed us to estimate the value of the dimensionless longitudinal radius of curvature δ/Rconf of the confuser part of the vapour channel, which is determined from the condition of minimal friction losses during the flow of moist vapour in the boundary layer δ along the concave wall of the confuser part of the vapour channel with a longitudinal radius of curvature Rconf. The concave diffuser part shape of the vapour channel is determined by the condition that the moving vapour jets velocity vectors must be parallel to the longitudinal axis of the diffuser part of the HP’s vapour channel. The results of the numerical simulation of the hydraulic resistance coefficients ξvp of the HP’s vapour channel, closed with flat covers, with partially swirling jet vapour flow, obtained by using the ANSYS FLUENT program, show a decrease in ξvp coefficients at high values of the evaporator temperature load, in the range of vapour flow velocities 1 m/s z ≤ 100 m /s, and in the range of swirling angles 0°30°, a sharp increase in the hydraulic resistance coefficient ξvp begins.
    },
     year = {2023}
    }
    

    Copy | Download

  • TY  - JOUR
    T1  - The Increasing of the Heat Transfer Coefficient of Short Linear Heat Pipes
    AU  - Seryakov Arkady Vladimirovich
    Y1  - 2023/11/17
    PY  - 2023
    N1  - https://doi.org/10.11648/j.ajmp.20231203.11
    DO  - 10.11648/j.ajmp.20231203.11
    T2  - American Journal of Modern Physics
    JF  - American Journal of Modern Physics
    JO  - American Journal of Modern Physics
    SP  - 30
    EP  - 46
    PB  - Science Publishing Group
    SN  - 2326-8891
    UR  - https://doi.org/10.11648/j.ajmp.20231203.11
    AB  - The results of the experimental studies of heat transfer coefficients KHP of short linear heat pipes (HP’s) with a Laval nozzle-liked vapour channel, and with a partially swirled vapour flow inside the channel are presented. A partial azimuthal swirling of the jet vapour stream is created using inclined injection channels 1 mm in diameter in a flat multilayer mech evaporator, with an inclination angle φ relative to the longitudinal axis in the azimuthal direction, in the range of 0° HP of a set of the identical HP’s with a different inclination angles φ of the injection channels in the evaporators, with the same working fluid mass filling (δm/m ≤ 0.1 %), at the same evaporator temperature heat load δT = Tev –TB = (20 ± 0.03) K, represent an extreme convex function, depending on the inclination angle φ magnitude of the injection channels, with a maximum at the swirled angle of the vapour flow φ = 26° ± 2°. The magnitude of the excess of the KHP with a swirling vapour flow over the identical HP’s with a direct vapour flow reaches 10%. An analysis of the recommended vapour channel shape, carried out by the estimating of the Richardson number Ri of the vapour flow jets above the evaporator, allowed us to estimate the value of the dimensionless longitudinal radius of curvature δ/Rconf of the confuser part of the vapour channel, which is determined from the condition of minimal friction losses during the flow of moist vapour in the boundary layer δ along the concave wall of the confuser part of the vapour channel with a longitudinal radius of curvature Rconf. The concave diffuser part shape of the vapour channel is determined by the condition that the moving vapour jets velocity vectors must be parallel to the longitudinal axis of the diffuser part of the HP’s vapour channel. The results of the numerical simulation of the hydraulic resistance coefficients ξvp of the HP’s vapour channel, closed with flat covers, with partially swirling jet vapour flow, obtained by using the ANSYS FLUENT program, show a decrease in ξvp coefficients at high values of the evaporator temperature load, in the range of vapour flow velocities 1 m/s z ≤ 100 m /s, and in the range of swirling angles 0°30°, a sharp increase in the hydraulic resistance coefficient ξvp begins.
    
    VL  - 12
    IS  - 3
    ER  - 

    Copy | Download

Author Information
  • LLC ‘Rudetransservice’, Veliky Novgorod, Russia

  • Sections