A distributed optical fiber sensor capable of measuring strain and/or temperature with high accuracy and high spatial resolution without requiring any manual adjustment. The distributed optical fiber sensor utilizing the Brillouin scattering phenomenon comprises a stepwise optical pulse light source generating an optical pulse having a stepwise distribution of light intensity increasing toward the center, a CW light source generating a continuous light, a sensing optical fiber which receives an optical pulse as a probe light and the continuous light as a pumping light and in which a Brillouin scattering phenomenon occurs between the probe light and the pump light, and a Brillouin time domain detector for determining the Brillouin loss or the gain spectrum from the light emerging from the sensing optical fiber and attributed to the Brillouin scattering phenomenon, and determining the distribution of strain caused in the sensing optical fiber in the longitudinal direction thereof and/or the distribution of temperature from the Brillouin loss or gain spectrum.

Distributed optical fiber sensor

Dust particulates in the size range of 10nm–100μm are found in all fusion devices. Such dust can be generated during tokamak operation due to strong plasma∕material-surface interactions. Some recent experiments and theoretical estimates indicate that dust particles can provide an important source of impurities in the tokamak plasma. Moreover, dust can be a serious threat to the safety of next-step fusion devices. In this paper, recent experimental observations on dust in fusion devices are reviewed. A physical model for dust transport simulation and a newly developed code DUSTT are discussed. The DUSTT code incorporates both dust dynamics due to comprehensive dust-plasma interactions as well as the effects of dust heating, charging, and evaporation. The code tracks test dust particles in realistic plasma backgrounds as provided by edge-plasma transport codes. The results are presented for dust transport in current and next-step tokamaks. The effect of dust on divertor plasma profiles and core plasma conta...

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Dust-particle transport in tokamak edge plasmas

Experimental study on the condensation of supersonic steam jet submerged in quiescent subcooled water: Steam plume shape and heat transfer

Experimental study on sonic steam jet condensation in quiescent subcooled water

Kazuyuki Takase

Papers

Numerical study on direct-contact condensation of vapor in cold water

Results of Two-Phase Flow Experiments with an Integrated Ingress-of-Coolant Event (ICE) Test Facility for ITER Safety

Three-Dimensional Numerical Simulations of Dust Mobilization and Air Ingress Characteristics in a Fusion Reactor during a LOVA event

Validation and benchmarking in support of ITER-FEAT safety analysis

Numerical prediction of augmented turbulent heat transfer in an annular fuel channel with repeated two-dimensional square ribs