DOI: 10.55176/2414-1038-2021-4-98-105
Authors & Affiliations
Levchenko V.A., Kascheev M.V., Dorokhovich S.L., Zaytsev A.A.
Limited Liability Company “Simulation Systems Ltd.”, Obninsk, Russia
 
 Levchenko V.A. – Director, Cand.  Sci. (Techn.). 
  Kascheev M.V. – Leading Researcher, Dr. Sci. (Techn.), Associate Professor. Contacts: 133, Lenin avenue,  Obninsk, Kaluga region, Russia, 249035. Tel.: +7 (484) 396-03-61; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.. 
  Dorokhovich S.L. – Chief Engineer, Cand. Sci.  (Techn.), Associate Professor. 
  Zaytsev A.A. – Head of the  Laboratory, Cand. Sci. (Techn.).
Abstract
The heat  conduction equation for an annular fin with an arbitrary profile in the  presence of energy release in the fin is obtained in the article. The resulting  equation differs from the approximate equation given in the literature by the  presence of energy release and a more accurate determination of the length of  the arc element. As boundary conditions, the temperature of the  base of the fin is set, and at the end of the fin, heat exchange occurs  according to the Newton  – Richmann law with the environment. The equation for the  fin of a rectangular profile is an inhomogeneous modified Bessel  equation. Its solution contains the Bessel functions of the imaginary argument  of the first and second kind of zero order. The efficiency of the fin and the  heat flow through the base of the fin are determined. The energy release in the  fin increases its efficiency compared to the efficiency of the fin in the  absence of energy release, and also reduces the heat flow. The  restriction by the values of energy release in the fin is found as condition  for the applicability of the finning. The fin efficiency must be less than one. If the efficiency exceeds one,  the fin plays the opposite role: the flow is directed in the reverse side. In the article, an expression is obtained for the  surface build-up coefficient kH. When  calculating the heating (cooling) of a body with a finned surface, the heat  transfer coefficient should be increased by kH  times.
Keywords
 surface finning, fins  with energy release, extended surface, the annular fin, the efficiency of the fin,  heat flow, heat  conduction equation for a fin, modified  Bessel functions
Article Text (PDF, in Russian)
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UDC 536.21
Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2021, issue 4, 4:9