Two distinct topics concerning SOL physics are examined. First, a novel magnetic divertor geometry is presented: 1) inducing a second axi-symmetric x-point downstream of main plasma x-point. For reactor relevant coils, field line lengths from the core x-point to the wall can be increased ~2-3 times, and flux expansion can be increased ~ 5 times. 2) the potential reactor consequences of large SO...

The issue of waste minimisation in advanced reactor systems has been investigated using the Particle-Bed Gas-cooled Fast Reactor (PB-GCFR) design being developed and funded under the U.S. Department of Energy Nuclear Energy Research Initiative (USDOE NERI) Programme. Results indicate that for the given core power density and constraint on the maximum TRU enrichment allowable, the lowest amount ...

A method is proposed for determining power-density profiles in nuclear reactor fuel rods from neutron flux measurements obtained by multiple in-core micropocket fission detectors (MPFD). A general formulation is presented that relates the power-density profiles in a reactor’s fuel rods to the flux density at detector locations. Key to this formulation is the construction of an appropriate respo...

Alain Delchambre Université libre de Bruxelles CP 165/41, 50 av. F.D. Roosevelt B-1050 Brussel, Belgium Abstract. In-core temperature measurement is a critical issue for the safe operation of nuclear reactors. Classical thermocouples require shielded connections and are known to drift under high neutron fluence. As an alternative, we propose to take advantage of the multiplexing capabilities of...

A new variant of a hybrid Monte Carlo–deterministic approach for simulating particle transport problems is presented and compared to the SCALE FW-CADIS approach. The new approach, denoted as the SUBSPACE approach, improves the selection of the importance maps in order to reduce the computational overhead required to achieve global variance reduction—that is, the uniform reduction of variance ev...

The background, basis, feasibility, structure, evidence and geophysical implications of a naturally occurring Terracentric nuclear fission georeactor are reviewed. For a nuclear fission reactor to exist at the centre of the Earth, all of the following conditions must be met: (1) There must originally have been a substantial quantity of uranium within Earth’s core. (2) There must be a natural me...

At the ENEA TRIGA research reactor (Casaccia Research Center, Rome), a new neutron collimator has been designed and installed at the neutron tangential channel. This collimator, that is part of a neutron/X-ray facility for NDT analysis, was experimentally characterized and optimized in terms of thermal neutron flux, its spatial/energetic distribution, photon air KERMA and effective beam diamete...