EDN: EWRUVO
Authors & Affiliations
Alekseev P.A., Pyshko A.P., Ruzhnikov V.A., Ivanov A.S.
 A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia
 
Alekseev P.A. – Senior  Researcher, Cand. Sci. (Tech.). Contacts: 1, pl. Bondarenko, Obninsk, Kaluga  region, Russia, 249033. Tel.: +7 (484) 399-70-00 (add 41-61); e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
     Pyshko A.P. – Head of  Department, Cand. Sci. (Phys.-Math.).
     Ruzhnikov V.A. – Candidate of  Engineering Sciences, Leading Researcher. Cand. Sci. (Tech.).
     Ivanov A.S. – Research Engineer. 
Abstract
The article  provides a brief description and results of calculations carried out using the  modified version of the TFEDM22 calculation program. TFEDM22 is developed to  evaluate the thermal and electro-physical characteristics (TEC) of the  thermionic fuel element (TFE) reactor-converter. In addition to traditional  heat transfer tasks, TFEDM22 implements heat transfer due to thermionic  current, making this code unique.
The modification of TFEDM22 involved implementing the capability to use  point-wise distribution of power release along the height of the TFE, directly  obtained from neutron-physical calculations. In the unmodified TFEDM22 code,  the distribution of power release along the height of the reactor is restored  using a cosine function with the application of the kz value.
The necessity for this modification is driven by the use of means to  equalize power release along the reactor's height, leading to significant  deviations in the power release distribution shape from the cosine function  shape.
The results of the comparative calculations show that using the cosine  function to restore the power release distribution can overestimate the  electric power values by 2 to 25 %.
This modification allowed the creation of an optimization code for  selecting the lengths of termionic fuel element, integrating neutron-physical  and thermal and electrophysical calculation programs with optimization  algorithms. As an optimization method, a genetic  algorithm was used, which has proven itself well in solving problems of  optimizing the core and radiation shield of a thermionic nuclear power unit.
The calculations showed that the developed optimization code finds  solutions that are no worse than the currently used method. Additionally, since  the entire process is automated, the time required to find such a solution is  reduced. 
Keywords
thermoelectrophysical calculation, power release  distribution shape, geometric optimization of TFE, genetic algorithm
 Article Text (PDF, in Russian)
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UDC 621.039.578:629.7
Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2025, no. 1, 1:5