The following information was submitted:
Transactions: INTERNATIONAL JOURNAL of SYSTEMS ENGINEERING, APPLICATIONS AND DEVELOPMENT
Transactions ID Number: 19-865
Full Name: Andrea Malizia
Position: Researcher
Age: ON
Sex: Male
Address: Via del Politecnico 1, zip code 00133 - Rome
Country: ITALY
Tel: 0672597196
Tel prefix: 0039
Fax: 0672597207
E-mail address: malizia@ing.uniroma2.it
Other E-mails: amalizia80@hotmail.com
Title of the Paper: RNG k- modelling and mobilization experiments of loss of vacuum in small tanks for nuclear fusion safety applications
Authors as they appear in the Paper: Pasquale Gaudio, Andrea Malizia, Ivan Lupelli
Email addresses of all the authors: malizia@ing.uniroma2.it
Number of paper pages: 19
Abstract: The objective of this work concerns the RNG k-ε modelling and mobilization experiments of loss of vacuum in small tanks for nuclear fusion safety applications. Activated dust mobilization during a Loss of Vacuum Accidents (LOVA) is one of the safety concerns for the International Thermonuclear Experimental Reactor (ITER). Intense thermal loads in fusion devices occur during plasma disruptions, Edge Localized Modes (ELM) and Vertical Displacement Events (VDE). They will result in macroscopic erosion of the plasma facing materials and consequent accumulation of activated dust into the ITER Vacuum Vessel (VV). These kind of events can cause the dust leakage outside the VV that represents a high radiological risk for the workers and the population. A small facility, Small Tank for Aerosol Removal and Dust (STARDUST), was set up at the ENEA Frascati laboratories to perform experiments concerning the dust mobilization in a volume with the initial condition similar !
to those existing in ITER VV. The aim of this work was to reproduce a low pressurization rate (300 Pa/s) LOVA event in a vacuum vessel due to a small air leakage for two different positions of the leak, at the equatorial port level and at the divertor port level, in order to evaluate the influence of obstacles and walls temperature on dust resuspension during both maintenance (MC) and accident conditions (AC) (Twalls=25°C MC, 110°C AC). The dusts used were • tungsten (W); • stainless steel 316 (SS316); • carbon (C). similar to those produced inside the vacuum chamber in a fusion reactor when the plasma facing materials vaporize due to the high energy deposition. The experimental campaign has been carried out by introducing inside STARDUST facility an obstacle to simulate the presence of objects, like divertor. In the obstacle a slit was cut to simulate the limiter-divertor gap inside ITER VV. The velocity magnitude in STARDUST was investigated in order to map the velo!
city field by means of a punctual capacitive transducer placed inside
STARDUST without obstacles. In this paper experimental campaign results are shown in order to investigate how the divertor and limiter-divertor gap influence dust mobilization into a VV. A two-dimensional (2D) modelling of STARDUST was made with the CFD commercial code FLUENT, in order to get a preliminary overview of the fluid dynamics behaviour during a LOVA event and to justify the mobilization data. Besides a numerical model was developed to compare numerical results with experimental ones.
Keywords: Dust mobilization, nuclear fusion, safety, LOVA, CFD, RNG
EXTENSION of the file: .pdf
Special (Invited) Session: Experimental and numerical analysis of dust resuspension for supporting chemical and radiological risk assessment in a nuclear fusion device
Organizer of the Session: 202-195
How Did you learn about congress: gaudio@ing.uniroma2.it
IP ADDRESS: 79.32.232.4
