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Suche nach „[Bonfigli] [Giuseppe]“ hat 14 Publikationen gefunden
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    NachhaltigMaschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    T. Wagner, S. Leyer, Giuseppe Bonfigli, Nadine Kaczmarkiewicz

    Performance of the Passive Core Flooding System in the Integral Tests of the Project EASY

    49. Jahrestagung Kerntechnik / 49th Annual Meeting on Nuclear Technology (AMNT 2018), Berlin , 29. - 30. Mai 2018

    2018

    Abstract anzeigen

    Among nuclear power generation plants, light water reactors are mainly used at present, and are anticipated to be predominant in the future. To improve the light water reactors the development of the LWRs for the next generation is carried out at various organizations. For example, in the USA the Westinghouse AP-1000 is based on proven technology but with an emphasis on passive safety features. The reactor passive core cooling systems include the core makeup tanks system, passive residual heat removal heat exchanger and in-containment refuelling water storage tank. In Russia has been developed the so-called NPP-2006 project of a VVER-1200 nuclear power plant with a V-392M reactor unit. To provide the safety, protection passive systems which don’t depend upon human errors are widely used in this project. Among these are hydrotanks of the second stage and passive heat removal system. In the presented paper an overview of passive core cooling systems for next generation NPPs is given.

    NachhaltigMaschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    T. Wagner, N. Neukam, Giuseppe Bonfigli, Nadine Kaczmarkiewicz, S. Buchholz, F. Schäfer, W. Klein-Hessling

    The Code System AC2 for the Simulation of Advanced Reactors within the Frame of the German EASY Project

    Proceedings of the 17th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-17) [September 3-8, 2017; Qujiang Int’l Conference Center, Xi’an, Shaanxi, China]

    2017

    NachhaltigMaschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    T. Wagner, N. Neukam, Giuseppe Bonfigli, Nadine Kaczmarkiewicz, S. Buchholz, F. Schäfer, A. Schaffrath

    Evidence of Design Basis Accidents Mitigation Solely with Passive Safety Systems within the Frame of the German EASY Project

    Proceedings of the 17th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-17) [September 3-8, 2017; Qujiang Int’l Conference Center, Xi’an, Shaanxi, China]

    2017

    NachhaltigMaschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    T. Wagner, S. Leyer, Giuseppe Bonfigli, Nadine Kaczmarkiewicz

    Influence of Two-Phase Reverse Flow in the Passive Core Flooding System: Experiments and Simulations within the Frame of the German EASY Project

    Proceedings of the 17th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-17) [September 3-8, 2017; Qujiang Int’l Conference Center, Xi’an, Shaanxi, China]

    2017

    Maschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    M. Kloker, Giuseppe Bonfigli, S. Wagner

    3-D-boundary-layer transition induced by superposed steady and travelling crossflow vortices

    High performance computing in science and engineering '02, [S.l.]

    2014

    ISBN: 978-3-642-63947-0

    Maschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    P. Jenny, Giuseppe Bonfigli

    Application of the multi-scale-finite-volume method to the simulation of incompressible flows with immersed boundaries

    New results in numerical and experimental fluid mechanics, Berlin; Heidelberg, vol. 112

    2010

    ISBN: 978-3-642-14242-0

    Maschinenbau und Mechatronik

    Zeitschriftenartikel

    P. Jenny, Giuseppe Bonfigli

    An efficient multi-scale Poisson solver for the incompressible Navier-Stokes equations with immersed boundaries

    Journal of Computational Physics, vol. 228, no. 12, pp. 4568-4587

    2009

    Abstract anzeigen

    The iterative-multi-scale-finite-volume (IMSFV) procedure is applied as an efficient solver for the pressure Poisson equation arising in numerical methods for the simulation of incompressible flows with the immersed-interface method (IIM). Motivated by the requirements of the specific IIM implementation, a modified version of the IMSFV algorithm is presented to allow the solution of problems, in which the varying coefficient of the elliptic equation (e.g. the permeability of the medium in the context of the simulation of flows in porous media) varies over several orders of magnitude or even becomes zero within the integration domain. Furthermore, a strategy is proposed to incorporate the iterative procedure needed by the IIM to converge out constraints at immersed boundaries into the iterative IMSFV cycle. No significant deterioration of performance of the IMSFV method is observed with respect to cases, in which no iterative improvement of the boundary conditions is considered.

    Maschinenbau und Mechatronik

    Zeitschriftenartikel

    Giuseppe Bonfigli

    Numerical solution of the incompressible Navier-Stokes equations with explicit integration of the pressure term

    Proceedings in Applied Mathematics and Mechanics (PAMM), vol. 7, no. 12, pp. 4100019-4100021

    2007

    Abstract anzeigen

    We propose a formulation of the incompressible Navier-Stokes equations considering a Poisson equation with Neumann boundary conditions for the pressure, and innovative boundary conditions for the velocity. Numerical tests show that the proposed formulation ensures solenoidality of the velocity field. If the initial condition is not divergence-free, exponential decay is observed in time for the error in the fulfillment of the continuity equation.

    Maschinenbau und Mechatronik

    Zeitschriftenartikel

    M. Kloker, Giuseppe Bonfigli

    Secondary instability of crossflow vortices: validation of the stability theory by direct numerical simulation

    Journal of Fluid Mechanics, vol. 583, pp. 229-272

    2007

    Abstract anzeigen

    Detailed comparison of spatial direct numerical simulations (DNS) and secondary linear stability theory (SLST) is provided for the three-dimensional crossflow-dominated boundary layer also considered at the DLR-Göttingen for experiments and theory. Secondary instabilities of large-amplitude steady and unsteady crossflow vortices arising from one single primary mode have been analysed. SLST results have been found to be reliable with respect to the dispersion relation and the amplitude distribution of the modal eigenfunction in the crosscut plane. However, significant deviations have been found in the amplification rates, the SLST results being strongly dependent on the necessarily simplified representation of the primary state. The secondary instability mechanisms are shown to be local, i.e. robust with respect to violations of the periodicity assumption made in the SLST for the wall-parallel directions. Perturbations associated with different local maxima of the spanwise periodic eigenfunctions develop independently from each other interacting only with the primary vortices next to them. Characteristic structures induced by different secondary instability modes have been analysed and an analogy with the Kelvin–Helmholtz instability mechanism has been highlighted.

    Maschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    M. Kloker, Giuseppe Bonfigli

    Secondary instability of superposed steady and unsteady crossflow vortices

    New results in numerical and experimental fluid mechanics IV, Berlin; New York, vol. 87

    2004

    ISBN: 978-3-540-20258-5

    Maschinenbau und Mechatronik

    Vortrag

    M. Kloker, Giuseppe Bonfigli

    Comparison of DNS and stability theory with respect to the secondary instability of crossflow vortices

    Euromech Fluid Mechanic Conference (EFMC) 2003, Toulouse, Frankreich

    2003

    Maschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    M. Kloker, Giuseppe Bonfigli

    Spatial Navier-Stokes simulation of crossflow-induced transition in a three-dimensional boundary layer

    New results in numerical and experimental fluid mechanics, Berlin; Heidelberg; New York, vol. 11

    2001

    ISBN: 978-3-540-41552-7

    Maschinenbau und Mechatronik

    Beitrag (Sammelband oder Tagungsband)

    M. Kloker, Giuseppe Bonfigli

    Three-dimensional Boundary-Layer Transition Phenomena Investigated by Spatial Direct Numerical Simulation

    Laminar-Turbulent Transition, Berlin, Heidelberg

    2000

    ISBN: 978-3-642-08752-3

    Maschinenbau und Mechatronik

    Hochschulschrift

    Giuseppe Bonfigli

    Numerical simulation of transition and early turbulence in a 3-d boundary layer perturbed by superposed stationary and traveling crossflow vortices