Abstract
The paper studies a primary-to-secondary leak of nitrogen radionuclide 16N (T1/2 = 7.11 s, Eγ, max = 6.134 MeV, \({{{v}}_{{\gamma ,\max }}}\) = 69%) through a steam generator in a KLT-40 type reactor (used in ice breakers and floating power units, FPUs) with an ingress of water under pressure \({{P}_{{v}}}\) and temperature \({{T}_{{v}}}\) heated by a follow-up radioactive steam generation which is released under high pressure Pp through a helical steam duct of the steam generator. The content of the specified radionuclide in steam can be found and estimated by use of methods of gamma spectrometry and measurement of γ-activity concentration of steam and γ-radiation dose rate through the use of a simple physical and mathematical model making it possible to specify the reason and to determine the area of a leakage on a helical steam duct. The paper specifies the main areas in the structure of steam generators where radiation characteristics may be measured and their assessment techniques may be applied.
Notes
KLT-40—pressurized water nuclear reactor, developed at OKBM Afrikantov. Manufactured at the Nizhny Novgorod Machine-Building Plant. This type of reactor is widely used on icebreakers and floating power units (FPUs).
This type of steam generator is typical for KLT-40 reactors and other pressurized water nuclear reactors [6].
The speed of steam at its exit from the steam pipeline at the indicated values of temperature and pressure in Fig. 1, according to estimates, is ~600 m/s, and the average is 566 m/s. At such speeds of steam exit to the turbine rotor blades, a very high radial speed of the turbine would develop, which would entail a significant increase in centrifugal force, which would lead to a colossal increase in stresses in the turbine disk and especially in the rotor blades, which would lead to an excess of the allowable stresses of these structures and, as a result, to their destruction. These possible effects lead to the need to reduce the pressure and temperature of the steam by using appropriate technical solutions. https://tesiaes.ru/?p=8414 [in Russian].
If the water-steam pipeline is made in the form of a spiral with radius Rsp with step hsp, then, with the length of the water–steam boundary region equal to ΔL0, the area of this region Sbpr is defined by the expression Sbor = (ΔL0/hsp) × 4π2Rsp(Rin + Rex)/2, where Rin and Rex are the inner and outer radii of the water-steam pipeline, respectively.
REFERENCES
E. A. Ivanov, I. V. Pyrkov, and L. P. Kham’yanov, Sov. At. Energy 73, 543 (1992).
E. A. Ivanov, I. V. Pyrkov, and L. P. Kham’yanov, At. Energy 105, 543 (2008).
RD EO 0334-02 (VNIIAES, 2002).
Radiation Safety Standards NRB—99/2009, Sanitary Rules and Regulations SanPiN 2.6.1.2523 (2009).
N. G. Gusev and P. P. Dmitriev, Quantum Radiation of Radioactive Nuclides, Reference Book (Atomizdat, Moscow, 1997) [in Russian].
V. I. Deev, N. V. Shchukin, and A. L. Cherezov, Fundamentals of Calculation of Ship Nuclear Power Plants, The School-Book, Ed. by V. I. Deev (NIYaU MIFI, Moscow, 2012) [in Russian]; Reactor Plant KLT-40, on the Example of the Nuclear Power Plant of the Lighter Carrier SevMorPut. http://www.nucon.us/archives/2950.
A. Nikitin and L. Andreev, Floating Nuclear Power Plants, Report of the Bellona Association (2011).
I. N. Vorob’ev and A. A. Khashchenko, in Proceedings of the 2nd International Conference Youth and Science Forum: Natural and Medical Sciences, No. 2 (2). https://nauchforum.ru/archive/mnf_nature/2.pdf. Accessed January 16, 2019.
A. P. Elokhin and S. N. Fedorchenko, Glob. Yad. Bezopasn., No. 3 (32), 7 (2019).
S. A. Sardanashvili, Calculation Methods and Algorithms (Pipeline Transport of Gas) (Neft’ Gaz, Moscow, 2005) [in Russian].
R. R. Kimel’ and V. P. Mashkovich, Protection against Ionizing Radiation, Reference Book (Atomizdat, Moscow, 1966) [in Russian].
A. P. Elokhin and S. N. Fedorchenko, RF Patent No. 2754755, Byull. Izobret., No. 25 (2021).
A. P. Elokhin, Methods and Means of Environmental Radiation Monitoring Systems (NIYaU MIFI, Moscow, 2014) [in Russian].
A. P. Elokhin, A. I. Ksenofontov, Issa Alalem, and S. N. Fedorchenko, Glob. Yad. Bezopasn., No. 2 (27), 7 (2018).
GOST (State Standard) No. R8.585-2001: Thermocouples (2010).
Author information
Authors and Affiliations
Corresponding author
Supplementary Information
Rights and permissions
About this article
Cite this article
Elokhin, A.P., Fedorchenko, S.N. Determination of the Leakage Area of Radioactive Nitrogen 16N in Steam Generators in Reactors of KLT-40 Type. Phys. Atom. Nuclei 85 (Suppl 2), S42–S49 (2022). https://doi.org/10.1134/S106377882214006X
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S106377882214006X