On Some Fundamental Peculiarities of the Traveling Wave Reactor

V D Rusov,S I Kosenko,M E Beglaryan,T N Zelentsova,V P Smolyar,I V Sharph,E P Linnik,V N Vashchenko,V A Tarasov,S A Chernegenko

doi:10.1155/2015/703069

V D Rusov, S I Kosenko + Show 8 more

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https://doi.org/10.1155/2015/703069

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Abstract

On the basis of the condition for nuclear burning wave existence in the neutron-multiplying media (U-Pu and Th-U cycles) we show the possibility of surmounting the so-called dpa-parameter problem and suggest an algorithm of the optimal nuclear burning wave mode adjustment, which is supposed to yield the wave parameters (fluence/neutron flux, width and speed of nuclear burning wave) that satisfy the dpa-condition associated with the tolerable level of the reactor materials radioactive stability, in particular that of the cladding materials. It is shown for the first time that the capture and fission cross sections of238U and239Pu increase with temperature within 1000–3000 K range, which under certain conditions may lead to a global loss of the nuclear burning wave stability. Some variants of the possible stability loss due to the so-called blow-up modes (anomalous nuclear fuel temperature and neutron flow evolution) are discussed and are found to possibly become a reason for a trivial violation of the traveling wave reactor internal safety.

Highlights

Despite the obvious and unique effectiveness of nuclear energy of the new generation, there are difficulties of its understanding related to the nontrivial properties of an ideal nuclear reactor of the future.First, nuclear fuel should be natural, that is, nonenriched uranium or thorium
The essence of these problems usually comes to a principal impossibility of such project realization and is defined by the following insurmountable flaws: (i) high degree of nuclear fuel burnup leading to the following adverse consequences: (a) high damaging dose of fast neutrons acting at at the constructional materials (∼500 dpa) (for comparison, the claimed parameters for the Russian FN-800 reactor are 93 dpa; at the same time, it is known that one of the main tasks of the construction materials radioactive stability investigations conducted at the Bochvar Hi-tech Institute for nonorganic materials (Moscow) is to achieve 133 to 164 dpa by 2020!), (b) high gas release, which requires an increased gas cavity length on top of a long fuel rod as it is
Earlier we noted the fact that due to a coolant loss at the nuclear reactors during the Fukushima nuclear accident the fuel was melted, which means that the temperature inside the active zone reached the melting temperature of uraniumoxide fuel at some moment, that is, ∼3000 K

Summary

Introduction

Despite the obvious and unique effectiveness of nuclear energy of the new generation, there are difficulties of its understanding related to the nontrivial properties of an ideal nuclear reactor of the future. The main goal of the present paper is to solve the specified technological problems of the TWR on the basis of a technical concept which makes it impossible for the damaging dose of the fast neutrons in the reactor (fuel rods jackets, reflection shield, and reactor pit) to exceed the ∼200 dpa level The essence of this technical concept is to provide the given neutron flux on in-reactor devices by defining the speed of the fuel movement relative to the nuclear burning wave speed. It reveals a possibility of the purposeful (in terms of the required neutron fluence and nuclear burning wave speed values) variation of the initial nuclear fuel composition.

On Entropy and Dispersion of Solitary

Control Parameter and Condition of Existence of Stationary

Possible Causes of the TWR Inherent

The Blowup Modes in Neutron-Multiplying Media and the Pulse Thermonuclear TWR

Findings

Conclusions