On some fundamental peculiarities of the traveling wave reactor

TL;DR

This paper explores the fundamental peculiarities of the traveling wave reactor, proposing an algorithm for optimal wave mode adjustment to ensure material stability and analyzing temperature effects on nuclear cross-sections that impact reactor stability.

Contribution

It introduces a new algorithm for optimizing nuclear burning wave parameters and reveals temperature-dependent cross-section behaviors affecting reactor stability.

Findings

Proposed an algorithm for optimal nuclear burning wave mode adjustment.

Discovered that U-238 and Pu-239 cross-sections increase with temperature, potentially destabilizing the wave.

Discussed possible stability loss mechanisms due to blow-up modes.

Abstract

On the basis of the condition for nuclear burning wave existence in the neutron-multiplicating 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 of $^{238}$U and $^{239}$Pu increase with temperature within 1000-3000K 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.