High-performance and simplify study on replacing a secondary loop of FBR with a tank.

For the purpose of cost reduction of loop type FBR while keeping same safety level我们提供AIHX （Advanced Intermediate Heat eXchanger）which is a combined IHX/SG simplified module. The long size heating apparatus was fabricated in 1998Liquid metal Ga was used as an intermediate heat transfer medium. Liquid metal Ga was used as an intermediate heat transfer medium.1999年Ga circulation loop was added to the apparatus with a circulation pump， Ga circulation loop was added to the apparatus with a circulation pumpand series of forced circulation heat transfer experiments performed with a parameter of Pe？500. A summary was described below.(1) Forced convective heat transfer characteristics of AIHX withGa as工作fluid. Heat transfer coefficient in the heating section was found to fall on a region（100【less than or equal】Pe【less than or equal】500）higher than Subboti'n equation（Nu=5+0.025Pe - d10.8 - D1） and correlation function of Nu=5+0.05Pe - d10.8 - D1 was obtained. In thecooling section,heat transfer coefficient fell on a region higher than Hoe's equation （Nu=0.43+0.228Pe）and correlation of Nu=6.34+0.256Pe D10.67 D was obtained. These data show a good heat transfercharacteristic of AIHX. 2 . Temperature fluctuation and an analysis of local fluid motion andtransfer mechanism In the heating sectiona local flow velocity estimated by the cross correlation method showed a good agreement with the EMFRMS value of temperature fluctuation was found to have A peak in A velocity change. Thissuggests that fluctuation is generated by temperature gradient and fluid disturbance mixed(3) Feasibility of AIHX as a replaced heat exchange er in FBRWith using a natural convectiveheat transfer scaled from the present data，heat transfer has estimated to be almost the same with or slightly better than Monju in性能。If it is designed to used with forced convection，the AIHX will be better than the present design base for Monju。

For the purpose of cost reduction of loop type FBR while keeping same safety level, we proposed AIHX (Advanced Intermediate Heat eXchanger), which is a combined IHX/SG simplified module. The long size heating apparatus was fabricated in 1998 and was used as a test channel. Liquid metal Ga was used as an intermediate heat transfer medium. In 1999, Ga circulation loop was added to the apparatus with a circulation pump, and series of forced circulation heat transfer experiments were performed with a parameter of Pe?500. A summary was described below.(1) Forced convective heat transfer characteristics of AIHX with Ga as working fluid. Heat transfer coefficient in the heating section was found to fall on a region (100【less than or equal】Pe【less than or equal】500) higher than Subboti'n equation (Nu=5+0.025PeィイD10.8ィエD1) and correlation function of Nu=5+0.05PeィイD10.8ィエD1 was obtained. In the cooling section, heat transfer coefficient fell on a region higher than Hoe's equation (Nu=0.43+0.228PeィイD10.67ィエD1), and correlation of Nu=6.34+0.256PeィイD10.67ィエD1 was obtained. These data show a good heat transfer characteristic of AIHX.(2) Temperature fluctuation and an analysis of local fluid motion and transfer mechanism In the heating section, a local flow velocity estimated by the cross correlation method showed a good agreement with the EMF value. A RMS value of temperature fluctuation was found to have a peak in a velocity change. This suggests that fluctuation is generated by temperature gradient and fluid disturbance mixed mechanism.(3) Feasibility of AIHX as a replaced heat exchanger in FBRWith using a natural convective heat transfer scaled from the present data, the heat transfer has estimated to be almost the same with or slightly better than Monju in performance. If it is designed to used with forced convection, the performance of the AIHX will be better than the present design base for Monju.