Izvestiya vuzov. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

Minimize fission power peaking factor in radial direction of water-cooled and water-moderated thermionic conversion reactor core

11/28/2017 2017 - #04 Physics and technology of nuclear reactors

Alekseev P.A. Krotov A.D. Ovcharenko M.K. Linnik V.A.

DOI: https://doi.org/10.26583/npe.2017.4.03

UDC: 621.039.578:629.7

In this work we investigate the feasibility of minimizing the fission power peaking factor in radial direction of the thermionic conversion reactor (TCR) core. Due to the high nonuniformity of the power density the reactors electrical power reduces and the temperature of thermionic fuel elements (TFE) increases. This impacts the reactors lifetime.

In the core of a TCR with intermediate spectrum of neutron, thermionic fuel elements are located on concentric circles. This provides the nonuniformity of location TFE and allows reducing the fission power peaking factor. In the core of an earth-based TCR a larger number of TFE are located on hexagonal lattice with a uniform step.

Minimization of the fission power peaking factor can be achieved by using the nuclear profiling or installing additional constructions in the core. The first approach requires creating of some different types of TFE, the second might cause the degradation of reactors neutronic parameter. All this impacts the projects economic viability.

In this work we propose to split the core in sections, each of them having its uniform step on the hexagonal lattice. Moreover the step of lattice increases from center to periphery resulting in reducing the fission power peaking factor to 1,06. Number of sections is determined by step of lattice, type and size of the TFE, dimensions of the reflector and reactors design constraints. The optimal lattice step for each section can be determined using a genetic algorithm based method which can find the solution while satisfying a number of given constraints. This method does not require any significant increase of the reactors dimensions, development and accounting of new types of TFE or additional constructions in the core.


  1. Kuznetsov V.A. Yadernye reactory kosmicheskih energeticheskih ustanovok [Nuclear reactors of space nuclear power unit]. Moscow. Atomizdat Publ., 1977, 240 p. (in Russian)
  2. Lazarenko G.E., Yarygin V.I, Pyshko A.P., Ovcharenko M.K., Miheev A.S., Linnik V.A., Krotov A.D., Lazarenko D.G., Son’ko A.V. Avtonomnaya yadernaya energeticheskaya ustanovka elektro- i teplosnabzheniya pryamogo preobrazovaniya teplovoj energii v elektichestvo [Autonomus nuclear power station for electricity and termal supply of direct conversion thermal energy for electricity] Sbornik dokladov Mezhdunarodnoj nauchno-prakticheskoj konferencii «Malaya energitika» [Proc. Int. Scientific-Practical Conference «Small Power Generation»], Moscow, 2006, pp. 68-70. (in Russian).
  3. Krotov A.D., Lazarenko G.E., Ovcharenko M.K.,Pyshko A.P., Son’ko A.V., Yarygin V.I., Lazarenko D.G. Avtonomnaya termoemissionnaya yadernaya energeticheskya ustanovka dlya gazo- i neftedobyvayuschih platform [Autonomus termonuclear nuclear power unit for oil and gas structures]. Izvestiya vuzov. Yadernaya energetika, 2011, no. 3, pp. 21-37 (in Russian).
  4. Maslov P.A. Electrisity generation system small nuclear power plant using high effective low temperature thermionic process. Izvestiya vuzov. Yadernaya energetika, 2011, no. 2, pp. 24-33 (in Russian).
  5. Atomnaya stanciya maloy moschnosti 10100 kWtel [Small thermionic nuclear power plant 10100 kWtel]. Available at: http://www.ippe.ru/innov/1/in1-7.php (accessed 24 Nov. 2016) (in Russian).
  6. Yarygin V. I., Rujnikov V.A., Sinayvskii V.V. Kosmicheskie i nazemnye yadernye energeticheskie ustanovki praymogogo preobrazovaniya energii. [Space and planetary nuclear power unit with direct energy conversion.]. Moscow. NIYaU MIFI Publ., 2016, 364 p. (in Russian).
  7. Polous M. A., Alekseev P. A., Ekhlakov I. A. Modern computational technologies for justification the characteristics of nuclear power propulsion systems in design works of creation a new generation of thermionic space nuclear power unit. Elektronnyj zhurnal Trudy MAI, 2013, iss. 68, 26 p. (in Russian). Available at: http://www.mai.ru/science/trudy/published.php?ID=41822
  8. Zabud’ko A.N., Linnik V.A., Raskach F.P. Sravnenie i analiz haracteristik termissionnyh reaktorov- preobrazovarelej razlichnogo tipa dlya kosmicheskih YaEU. Preprint GNC RF FEI-3025. [Comparision and analysis parameter of thermionic conversion reactor for space NPU: IPPE Preprint-3025]. Obninsk, FEI Publ., 2004, 28 p. (in Russian).
  9. Polous M. A., Yarygin V. I., Vinogradov E.G. [Programnyj kompleks dlya tryohmernogo chislennogo rascheta teplovyh i elektricheskih harakteristik mnogoelementnogo elekrogeneriruyuschego kanala termoemissionnoy YaEU [Program complex for three-dimensional numerical calculation of thermal end electricity property for multiple-elements fuel elements of thermionic NPU]. Izvestiya vuzov. Yadernaya energetika, 2012, no.2, pp.151-160 (in Russian).
  10. Linnik V.A. Raschyotno-teoreticheskie metody issledovaniya vyhodnyh harakteristik termoemisssionnyh elektrogeneriruyuschikh sborok (kanalov) i reaktorov-preobrazovateley kosmicheskih YaEU. Preprint GNC RF FEI-3058.[Teoretical metod for research property of thermionic fuel end conversion reactor in space power unit: IPPE Preprint -3058]. Obninsk, FEI Publ., 2005, 70 p. (in Russian).
  11. Pupko V.Ya., Kuz’min V.I. Ispol’zovanie funkcionalov teorii vozmuschenij dlya minimizacii zagruzki reactorov s proizvol’nym spektrom neitronov [Application functional of perturbation theory for minimization of reactor loading for reactor with any neutron spectrum]. Atomnaya Energiya, 1968, v. 24, no. 3, pp. 231-235. (in Russian).
  12. Sacco W. F., Filho H. A. and Pereira C.M.N.A. Cost-based optimization of a nuclear reactor core design: a preliminary model. Proceedings of INAC, 2007.
  13. MCNP – General Monte Carlo N-Particle Transport code. LA-12625-M, Vers. 4B, 1997.
  14. ENDF/B-VI Data for MCNP TM. LA-12891-M, 1994.
  15. Krotov A.D., Son’ko A.V, Raschyot neitronno-fizicheskih kharacteristik reactorf i radiatsionnoj zaschity v sostave YaEU kosmicheskogo naznacheniya s ispol’zovaniem programmnogo kompleksa MCNP [Application code MCNP for computation of neutron-physic reactor parameter and radiation protection space NPU]. Atomnaya Energiya, 2009, v. 106, no. 2, pp. 149-153. (in Russian).
  16. Bartolomei G.G., Bat’ G.A., Baibakov V.D., Altuhov M.S. Osnovy teorii i metody raschyota yadernykh energeticheskikh reaktorov. [Bases theory and methods for computation nuclear power reactor]. Moscow. Energoatomizdat Publ., 1989, 512 p. (in Russian).
  17. Konak A., Coit D.W., Smith A.E. Multi objective optimization using genetic algorithms. A tutorial. Reliability Engineering & System Safety. 2006, v. 91, pp. 992-1007.
  18. Gladkov L.A., Kureichik V.V., Kureichik B.M. Geneticheskie algoritmy [Genetic algorism]. Moscow. FIZMATLIT Publ., 2010, 368 p. (in Russian).
  19. Alekseev P.A. The search an optimal locations scheme for thermionic fuel elements in the core of space thermionic conversion reactor. Izvestiya vuzov. Yadernaya energetika, 2011, no. 2, pp. 51-61 (in Russian).
  20. Alekseev P.A. Advancement of optimization method for core of space thermionic conversion reactor. Proc. of Results of scientific and technical activities of Institute of nuclear reactors and thermophysics in 2011. Obninsk. SSC RF-IPPE Publ., 2012, pp 381-388 (in Russian).

thermionic conversion reactor thermionic fuel elements fission power peaking factor step of lattice genetic algorithm optimization