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Takada, Shoji; Ngarayana, I. W.*; Nakatsuru, Yukihiro*; Terada, Atsuhiko; Murakami, Kenta*; Sawa, Kazuhiko*
Proceedings of 27th International Conference on Nuclear Engineering (ICONE-27) (Internet), 13 Pages, 2019/05
In the loss of core cooling test using HTTR, a technical issue is to improve prediction accuracy of temperature distribution of components in vessel cooling system (VCS). An establishment of reasonable 2D model was started by using numerical code FLUENT, which was validated using the test data by 1/6 scale model of VCS for HTTR. The pressure vessel (PV) temperature was set around 200
C attributed to relatively high ratio of natural convection heat transfer around 20% in total heat removal, which is useful for code to experiment benchmark to improve prediction accuracy. It is necessary to confirm heat transfer flow characteristics around the top of PV which is heated up by natural convection flow which was considered to be affected by separation, re-adhesion and transition flow. The k-
-SST model was selected for turbulent calculation attributed to predict the effects mentioned above adequately. The numerical results using the k--SST model reproduced the temperature distribution of PV especially the top region which is considered to be affected by separation, re-adhesion and transition flow in contract to that using k-
model which does not account the effects.
Takamatsu, Kuniyoshi; Hu, R.*
Proceedings of 10th International Topical Meeting on Nuclear Thermal Hydraulics, Operation and Safety (NUTHOS-10) (USB Flash Drive), 12 Pages, 2014/12
continuous closed regions; one is an ex-reactor pressure vessel (RPV) region and another is a cooling region having heat transfer area to ambient air assumed at 40 (C). The RCCS uses novel shape so that the heat released from the RPV can be removed efficiently with radiation and natural convection. Employing the air as the working fluid and the ambient air as the ultimate heat sink, the new RCCS design greatly reduces the possibility of losing the heat sink for decay heat removal. Therefore, HTGRs and VHTRs adopting the new RCCS design can avoid core melting owing to overheating the fuels.
Tochio, Daisuke; Nakagawa, Shigeaki
JAERI-Tech 2005-041, 109 Pages, 2005/08
JAERI-Tech-2005-041.pdf:4.48MB
In High Temperature Engineering Test Reactor (HTTR) of 30MW, the generated heat at reactor core is finally dissipated at the air-cooler by way of the heat exchangers of the primary pressurized water cooler and the intermediate heat exchanger. To remove generated heat at reactor core and to hold reactor inlet coolant temperature to specified temperature, heat exchangers in main cooling system of HTTR should have designed heat exchange performance. In this report, heat exchange performance for ACL in main cooling system is evaluated with previous operation data, and evaluated values are compared with designed value. Moreover, heat exchange performance at full power operation is estimated for the air temperature. As the result, ACL has heat exchange performance removing generated heat at reactor core under the designe ACL inlet air temperature of 33C.
Katanishi, Shoji; Kunitomi, Kazuhiko; Tsuji, Nobumasa*; Maekawa, Isamu*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 3(3), p.257 - 267, 2004/09
no abstracts in English
Okano, Fuminori; Suzuki, Sadaaki
KEK Proceedings 2003-16 (CD-ROM), 4 Pages, 2004/02
A JFT-2M Tokamak auxiliary subsystem consists of a vacuum pumping system, a gas injection system, a leak detection system, a water cooling system, a glow discharge system, a boronization system, and a baking system. Control system of each part except for the baking system was replaced to new one, which utilizes a personal computer (PC), from FY 2000 to FY2002. The controllability of the system and the number of data, which can be recorded, was remarkably improved compared to the old system. This system has enough controllability for various operation condition of JFT-2M, and allows early finding and recovering of troubles. The general view of Tokamak auxiliary subsystem and detailed description of the function of the new control system are given in this report. It should be noted that this report describes detail of the operational procedure especially for He glow discharge system and the boron coating system, and thus, it can be used as an operation instruction.
Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Torii, Yoshikatsu; Hino, Ryutaro; Ikeda, Yujiro
Proceedings of ICANS-XVI, Volume 1, p.125 - 133, 2003/07
no abstracts in English
Okano, Fuminori; Suzuki, Sadaaki
JAERI-Tech 2003-059, 57 Pages, 2003/06
JAERI-Tech-2003-059.pdf:11.92MB
no abstracts in English
*; *; *; *; R.Haange*; Johnson, G.*; *; H.W.Bartels*; Y.Petrov*
Fusion Technology 1998, 2, p.1721 - 1724, 1998/00
no abstracts in English
Yamaki, Jikei; Fujikawa, Seigo; ; Ishida, Toshihisa; Mizushima, Toshihiko; *; Sakamoto, Yukio;
Genshiryoku Kogyo, 38(4), p.13 - 28, 1992/04
no abstracts in English
Takamatsu, Kuniyoshi; Matsumoto, Tatsuya*; Morita, Koji*
no journal, ,
After the accident at the Fukushima NPPs, measures to prevent core damage in terms of defense in depth had become more and more important. Researches regarding cooling system having novel safety features are crucially essential subjects. Therefore, a new Reactor Cavity Cooling System (RCCS) having passive safety features is proposed. The RCCS does not require active cooling systems and never lost heat sink in the same way as the accident at the Fukushima NPPs. The RCCS can become a base load cooling system like a base load power station and remove a part of emissive heat in rated operation and a part of decay heat after reactor shutdown, constantly, stably and passively.
