Publications related to Critical mass

Hidden-nucleons neural-network quantum states for the nuclear many-body problem

We generalize the hidden-fermion family of neural network quantum states to encompass both continuous and discrete degrees of freedom and solve the nuclear many-body Schrodinger equation in a systematically improvable fashion. We demonstrate that adding hi ...

AMER PHYSICAL SOC2022

Flowing Gas Experiments Reveal Mechanistic Details of Interfacial Reactions on a Molecular Level at Knudsen Flow Conditions

Christian Ludwig, Michel Rossi, Riccardo Iannarelli

Knudsen flow experiments and its interpretation in terms of adsorption/desorption kinetics as well as quantitative uptake on substrates of interest is presented together with the description of critical design parameters of the Knudsen Flow Reactor (KFR). ...

2022

The shear strength of Opalinus Clay shale in the remoulded state

Alessio Ferrari

The Opalinus Clay shale formation is considered as a potential host geomaterial for the Swiss deep geological repository for radioactive waste. It presents different facies and it is characterised by a multi-scale heterogeneous composition, by a typical fi ...

2020

Intercomparison of neutron noise measurement systems in the CROCUS reactor

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari, Mathieu Hursin

In the framework of an international collaboration, the critical decay constant (α0 = β/Λ), and delayed neutron fraction (β) of the CROCUS reactor were measured by teams of EPFL/PSI, CEA and SCK•CEN research institutes using the Rossi-α and Power Spectral ...

American Nuclear Society2018

Design of Separated Element Reflector Experiments in CROCUS: PETALE

Andreas Pautz, Vincent Pierre Lamirand, Pavel Frajtag, Mathieu Hursin, Daniel Jerôme Siefman

The present article describes the preliminary design studies for PETALE (Programme d'Etude en Transmission de l'Acier Lourd et ses Elements), an oncoming experimental program in the CROCUS reactor. Within the framework of the Venus-Eole-Proteus collaborati ...

ASTM INTERNATIONAL2018

Design of Separated Element Reflector Experiments in CROCUS: PETALE

Andreas Pautz, Vincent Pierre Lamirand, Pavel Frajtag, Mathieu Hursin, Daniel Jerôme Siefman, Stefan Radman

The present article describes the preliminary design studies for an oncoming experimental programme at the CROCUS facility. CROCUS is a teaching and research zero-power reactor operated by the Laboratory for Reactor Physics and Systems Behaviour (LRS) at t ...

2017

Comparison of Two Approaches for Nuclear Data Uncertainty Propagation in MCNPX for Selected Fast Spectrum Critical Benchmarks

Andreas Pautz, Hakim Ferroukhi, Dimitri Rochman, Tiankai Zhu, Alexander Vasiliev

Nuclear data uncertainty propagation based on stochastic sampling ( SS) is becoming more attractive while leveraging modern computer power. Two variants of the SS approach are compared in this paper. The Total Monte Carlo (TMC) method by the Nuclear Resear ...

Academic Press Inc Elsevier Science2014

Study of Nuclear Decay Data Contribution to Uncertainties in Heat Load Estimations for Spent Fuel Pools

Andreas Pautz, Mathieu Hursin, Hakim Ferroukhi, Alexander Vasiliev

At the Paul Scherrer Institut (PSI), a methodology for nuclear data uncertainty propagation in CASMO-5M (C5M) assembly calculations is under development. This paper presents a preliminary application of this methodology to C5M decay heat calculations. Appl ...

Academic Press Inc Elsevier Science2014

Experimental investigation of added mass effects on a hydrofoil under cavitation conditions

Mohamed Farhat, Eduard Egusquiza

The influence of leading edge sheet cavitation and supercavitation on the added mass effects experienced by a 2-D NACA0009 truncated hydrofoil has been experimentally investigated in a hydrodynamic tunnel. A non-intrusive excitation and measuring system ba ...

Elsevier2013

Stable self-similar blow up for energy subcritical wave equations

Roland Donninger

We consider the semilinear wave equation partial derivative(2)(t)psi - Delta psi = vertical bar psi vertical bar(p-1)psi for 1 < p

International Press2012

Design Aspects of a Deployable Tensegrity-Hollow-rope Footbridge

Ian Smith, Landolf-Giosef-Anastasios Rhode-Barbarigos, Nizar Bel Hadj Ali, René Motro

Tensegrity structures are composed of cables and struts in a prestressed self-equilibrium. Although tensegrity first appeared in the 1950s, it is seldom used in civil engineering. This paper focuses on the design aspects of a deployable tensegrity-hollow-r ...

2012

Measurement of Tc distribution in NbSn CICC

Pierluigi Bruzzone, Davide Uglietti, Ciro Calzolaio

Knowledge of the actual Nb3Sn filaments' thermal strain, epsilon(th), in a cable-in-conduit conductor (CICC) is essential to predict the CICC performance in operation starting from the strand scaling laws for the critical current density J(c)(B, T, epsilon ...

SUST 20122012

Appraisal of Core Analysis Methods against Zero-Power Experiments on Full-Scale BWR Fuel Assemblies

Flavio Dante Giust

The present doctoral research aims at the appraisal of nodal core simulators used for the calculation of commercial boiling water reactor (BWR) cores, against measurements carried out at the Paul Scherrer Institute under the LWR-PROTEUS experimental progra ...

EPFL2012

An Active Deployable Tensegrity Structure

Landolf-Giosef-Anastasios Rhode-Barbarigos

Tensegrity structures are spatial reticulated structures composed of cables and struts. Their stability is provided by a self-stress state among tensioned and compressed members. Although much progress has been made in advancing research into the tensegrit ...

EPFL2012

The important role of pressure in supercritical fluid process development revealed by reaction calorimetry

Thierry Meyer, Charalampos Mantelis

The technique of reaction calorimetry adapted for use with reactions in supercritical fluids was used to study some safety aspects of the free-radical dispersion polymerization of methyl methacrylate in scCO2. The reaction heat rate profile was found to ch ...

Wiley-Blackwell2009

Observation of Long-Lived Polariton States in Semiconductor Microcavities across the Parametric Threshold

The excitation spectrum around the pump-only stationary state of a polariton optical parametric oscillator in semiconductor microcavities is investigated by time-resolved photoluminescence. The response to a weak pulsed perturbation in the vicinity of the ...

2009

Estimating localised corrosion resistance of low alloy stainless steels: comparison of pitting potentials and critical pitting temperatures measured on lean duplex stainless steel LDX 2101 after sensitisation

Two different methods for estimating the corrosion resistance of low alloy stainless steels are compared: critical pitting temperature according to a modified ASTM G150 with a low chloride concentration (0.1M), and pitting potentials from polarisation curv ...

2008

BWR stability and bifurcation analysis using reduced order models and system codes: Identification of a subcritical Hopf bifurcation using RAMONA

Rakesh Chawla, Abdelhamid Dokhane

The system code RAMONA, as well as a recently developed BWR reduced order model (ROM), are employed for the stability analysis of a specific operational point of the Leibstadt nuclear power plant. This has been done in order to assess the ROM's applicabili ...

2007

Comparative transient analysis of critical and subcritical 80-MW Pb-Bi eutectic-cooled reactor systems

Rakesh Chawla, Konstantin Mikityuk

A consistent analytical comparison has been made of the transient behavior of critical and subcritical fast-spectrum reactor systems, the basic core design assumed in each case being that of the 80-MW(thermal) mixed-oxide-fueled, Pb-Bi-cooled, experimental ...

American Nucl. Soc.2007

A benchmark on the calculation of kinetic parameters based on reactivity effect experiments in the CROCUS reactor

Rakesh Chawla

Measurements in the CROCUS reactor at EPFL, Lausanne, are reported for the critical water level and the inverse reactor period for several different sets of delayed supercritical conditions. The experimental configurations were also calculated by four diff ...

Elsevier2006