XT-ADS WINDOWLESS TARGET HIGH RESOLUTION INTERFACE CAPTURING SIMULATIONS
Within the Integrated Project EUROpean Research Programme for the TRANSmutation of High Level Nuclear Waste in Accelerator Driven System (EUROTRANS) the first advanced design of an approximately 50 to 100 MWth eXperimental facility demonstrating the technical feasibility of Transmutation in an Accelerator Driven System (XT-ADS) is being developed. The spallation target for XT-ADS is windowless and employs heavy liquid metal (HLM). The proton beam hits the liquid metal directly through a free surface separating vacuum from HLM. The HLM is flowing downwards through an annular feeder line surrounding the beam tube and forms a conical free surface which is subjected to the proton beam. The thermal-hydraulics of the target must ensure a stable free surface, so that the heat deposited into the HLM can safely be removed. Preliminary experiments and simulations have shown that in the feeder tube cavitation may be observed leading to unacceptable unsteady disturbances of the free surface. A series of computations have lead to a fundamental understanding of the free target flow and a design which does no longer suffer from cavitation in the feeder line. The flow in the target and the feeder line can be simulated employing a volume of fluid (VoF) model which in addition accounts for phase change. Phase change occurs when the pressure falls below or rises above the vapour pressure. The cavitation model available in Star-CD simulates phase change by solving a Rayleigh-Plesset-equation describing the growth and collapse of vapour bubbles under varying pressure conditions is used in the target flow study Vapour bubbles emerge from seeds contained in the liquid. In the real target cavitation obviously must be omitted or only occurs during transients when the free surface flow is established. At stable operation of the target a distinct free surface is established rather than a cloud of cavitation bubbles. In the current work we present results of Star-CD simulations employing a high resolution interface capturing scheme in conjunction with the cavitation model, which is capable to both describe transients and nominal operation. The presentation covers both details of the numerics and the general design features, which lead to a very stable free surface configuration. Results are compared to experiments.
ADS VoF CFD turbulent flow free surface
Abdalla Batta Andreas G. Class
Karlsruhe Institute of Technology Institute for Nuclear and Energy Technologies Postfach 3640, 76021 Karlsruhe, Germany
国际会议
上海
英文
1532-1540
2010-10-10（万方平台首次上网日期，不代表论文的发表时间）