Journal: Nuclear Engineering and Design

Abbreviation

Nucl. eng. des.

Publisher

Elsevier

Journal Volumes

ISSN

0029-5493
1872-759X

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Publications 1 - 10 of 73
  • Application of the MiniPanda test case ‘erosion of a stratified layer bya vertical jet’ for CFD validation
    Item type: Journal Article
    Kelm, Stephan; Ritterath, Martin; Prasser, Horst-Michael; et al. (2016)
    Nuclear Engineering and Design
  • Natural circulation and stability performance of BWRs (NACUSP)
    Item type: Journal Article
    Aguirre, Carlos; Caruge, Daniel; Castrillo, Felix; et al. (2005)
    Nuclear Engineering and Design
  • Boiling water reactor stability revisited
    Item type: Conference Paper
    Yadigaroglu, George; Askari, B. (2005)
    Nuclear Engineering and Design
  • Distribution of trace substances in the coolant of a BWR fuel element
    Item type: Journal Article
    Robers, Lukas; Le Corre, Jean-Marie; Prasser, Horst-Michael (2023)
    Nuclear Engineering and Design
    A transport model was developed and numerically solved for trace substances dissolved in the coolant flowing through a complete BWR fuel element. The integration of the trace substance transport equations is carried out on the same computational grid used by a two-phase three-field subchannel code, the output of which provides the necessary coolant mass flow data, including field exchange terms. The results consist of complete, field specific trace substance distributions within the domain of the simulation and with the same spatial resolution as used by the subchannel code. Downstream the onset of annular flow, it was observed that the trace substance concentrations in liquid films on heated rods are significantly higher than the concentrations in droplets and in films on unheated surfaces. A mechanistic model for disturbance waves was further introduced to assess the additional trace substance concentration increase in the time period of base film evaporation between two successive disturbance waves. The highest trace substance concentrations were found next to part-length rods in the corner of the considered fuel assembly just upstream of the two uppermost spacer grids, which approximately corresponds to the location of trace substance deposition observed during fuel inspections at a Swiss nuclear power plant.
  • Development of a fast neutron imaging system for investigating two-phase flows in nuclear thermal-hydraulic phenomena
    Item type: Journal Article
    Zboray, Robert; Adams, Robert; Cortesi, Marco; et al. (2014)
    Nuclear Engineering and Design
  • Buoyant-diffusive flow in the HTGR air ingress accident scenario
    Item type: Journal Article
    Welker, Zachary; Manera, Annalisa; Petrov, Victor; et al. (2025)
    Nuclear Engineering and Design
    Experimental data from the Helium-Air Ingress gas-Reactor Experiment (HAIRE) has provided insight into an infrequently studied flow scenario where buoyant driven flow and molecular diffusion combine during an exchange flow. The combined buoyant-diffusive exchange flow occurs because of a transition region where buoyancy and molecular diffusion combine to create flow rates higher than the separate flow regimes would predict. The buoyo-diffusive flow is described by a dimensionless number which is used to quantitatively explain the results. The flow regime is of considerable importance in the small and medium-sized accident scenarios for High-Temperature Gas-cooled Reactors (HTGRs), where the flow regime will increase the air ingress rate in comparison to previously understood theory. For medium sized breaks the estimated increase in air ingress rate is up to 5% compared to the previous theory, and for small sized breaks the increase is either 5% or greater depending on the break size. This considerable increase in air ingress rates could affect the evolution of small- and medium-sized air ingress accidents and the overall damage to the HTGR's graphite core. Buoyo-diffusive exchange flow could manifest in other areas where small physical scales and high mass diffusion are present.
  • Status of the spent fuel in the reactor buildings of Fukushima Daiichi 1-4
    Item type: Conference Paper
    Jäckel, Bernd S. (2015)
    Nuclear Engineering and Design
  • Signal response of wire-mesh sensors to an idealized bubbly flow
    Item type: Journal Article
    Prasser, Horst-Michael; Häfeli, Richard (2018)
    Nuclear Engineering and Design
  • Response of electrical film thickness sensors to waves in the liquid film
    Item type: Journal Article
    Prasser, Horst-Michael (2021)
    Nuclear Engineering and Design
    The electrical liquid film thickness (LFT) sensor developed at ETH Zurich is applied to study wavy annular flows. The LFT sensor consists of a matrix of electrodes put flush to the surface of the wall at which the liquid film of interest is present. The conductance between transmitter and receiver electrodes is sampled and converted into a film thickness using a calibration function obtained for a flat liquid film without waves. Due to limited lateral resolution and non-linear sensor response, waves are characterized with measuring errors, which depend on the wave height, length and angle of attack. The paper presents the result of potential field simulations of waves passing over the sensor surface. The wave parameters obtained from the simulated sensor signals are compared to the input. The results are used to quantify the uncertainty of dynamic film thickness measurements. The obtained detailed information on the sensor response allows a better interpretation of experimental results.
  • URANS simulations of the single-phase mixing in a 4*4 LWR fuel bundle with mixing vanes, validated against a sub-channel experiment
    Item type: Journal Article
    Li, Xiaorong; Prasser, Horst-Michael; Niceno, Bojan (2020)
    Nuclear Engineering and Design
Publications 1 - 10 of 73