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Yamaji, Akifumi; Takizuka, Takakazu; Nabeshima, Kunihiko; Iwamura, Takamichi; Akimoto, Hajime
Proceedings of 2009 International Congress on Advances in Nuclear Power Plants (ICAPP '09) (CD-ROM), p.9366_1 - 9366_8, 2009/05
This study has been carried out in series with the other study, "Criticality of Low Enriched Uranium Fueled Core" to explore the possibilities of a solid reactor electricity generation system for supplying propulsion power of a deep space explorer. The design ranges of three different systems are determined with respect to the electric power, the radiator mass, and the operating temperatures of the heat-pipes and thermoelectric converters. The three systems are the solid thermal conduction system (STC), core surface cooling with heat-pipe system (CSHP), and the core direct cooling with heat-pipe system (CDHP). The evaluated electric powers widely cover the 1 to 100 kW range, which had long been claimed to be the range that lacked the power sources in space. Therefore, the concepts shown by this study may lead to a breakthrough of the human activities in space. The working temperature ranges of the main components, namely the heat-pipes and thermoelectric converters, are wide and cover down to relatively low temperatures. This is desirable from the viewpoints of broadening the choices, reducing the development needs, and improving the reliabilities of the devices. Hence, it is advantageous for an early establishment of the concept.
Takada, Shoji; Takizuka, Takakazu; Yan, X.; Kunitomi, Kazuhiko; Inagaki, Yoshiyuki
Nihon Kikai Gakkai Rombunshu, B, 75(749), p.11 - 18, 2009/01
Aerodynamic performance test was carried out using a 1/3 scale, 4-stage model of helium gas compressor to investigate an effect of end-wall over-camber to prevent decrease of axial velocity in end-wall boundary layer. The model compressor consists of a rotor, 500 mm in diameter, which is driven at a rotational speed of 10800 rpm. The rotor blade span of the first stage is 34 mm. The test was carried out under the condition that the helium gas pressure 0.88 MPa, temperature 30 
C, and mass flow rate 12.47 kg/s at the inlet. A 3-dimensional aerodynamic code, which was verified using the test data, showed that axial velocity was lowered by using a blade which increased the inlet blade angle around the end-wall region of the casing side in comparison with that using the original design blade, because the inlet flow angle mismatched with the inlet blade angle of the rotor blade. The overall adiabatic efficiency of the full scale 20-stage compressor was predicted 89.7% from the test data.
Yan, X.; Takizuka, Takakazu; Kunitomi, Kazuhiko; Itaka, Hidehiko*; Takahashi, Kunio*
Journal of Turbomachinery, 130(3), p.031018_1 - 031018_12, 2008/07
Times Cited Count：27 Percentile：72.48(Engineering, Mechanical)Helium compressor aerodynamics is challenged by the characteristically narrow and numerous-stage flowpath which enhances loss effects of blade surface and end wall boundary layers, secondary and clearance flows, and any occurrence of flow separation and stage mismatch. To meet efficiency and reliability requirements of nuclear application, baseline and advanced aerodynamic design techniques are incorporated with intent to mitigate the flowpath adverse working condition and losses. Design validation is carried out by test and test-calibrated 3D viscous CFD analysis on a subscale model compressor. The data and computational insights of overall performance and internal flow behavior are used to establish a performance model based on Reynolds number. The model applicable to all geometrically similar designs shows sensitive responses of aerodynamic efficiency to Reynolds number and surface roughness.
Takada, Shoji; Takizuka, Takakazu; Yan, X.; Kunitomi, Kazuhiko
Nihon Gasu Tabin Gakkai-Shi, 34(2), p.94 - 99, 2006/03
Gas Turbine High Temperature Gas Reactor GTHTR300 is a direct cycle system in which reactor outlet helium gas at 850C is used to drive gas turbine. The design direction was to improve economics by combining existing technologies without breakthrough far from current technology level. The power conversion system design employed non-inter cooled regenerative cycle. The 3-dimensional blade design of the turbine and compressor, in which inlet blade angle was matched with inlet angle of flow, achieved high polytropic efficiencies of 93% and 90%, although they have disadvantages of high boss ratio and stage numbers. As the results of the design, the electric cost was estimated to be below 4 yen/kWh showing the economic competitiveness against LWRs. To establish design method of high efficiency helium gas compressor, a 1/3 scale compressor model aerodynamic performance test was carried out to design the inlet blade angle around the endwall to reduce endwall boundary layer thickness, as well as to modify coefficients of correlations for design. The design of high efficiency helium gas compressor was completed to fulfill the target efficiency of 90.5%.
Takada, Shoji; Takizuka, Takakazu; Yan, X.; Kurokochi, Naohiro; Kunitomi, Kazuhiko
JAEA-Technology 2005-007, 241 Pages, 2006/02
JAEA-Technology-2005-007.pdf:48.98MB
Because the main pipe is connected perpendicular to the flow direction inside the distributing header in the inlet casing of the helium gas compressor design of GTHTR300, the main flow flowing into the header tends to separate from the header wall and to cause reverse flow, which increases flow resistance in the header. This phenomenon increases the total pressure loss in the header and inlet distortion, which is considered to deteriorate the aerodynamic performance of the compressor. Tests were carried out to evaluate the effects of inlet distortion on aerodynamic performance of compressor by using a 1/3-scale helium gas compressor model by varying a level of inlet distortion. Flow was injected from the wall of header to adjust circumferential velocities uniform before and after the inverse flow region to dissipate the separation and inverse flow. At the rated flow point, inlet distortion was reduced 2-3 % by injection, which resulted in increasing adiabatic efficiency of blade section around 0.5 %. At the same time, pressure loss of the inlet casing was reduced around 3-5%, which is equivalent to adiabatic efficiency improvement around 0.8%. Surge flow rate was lowered from 10.0 kg/s to 9.6 kg/s. By setting orifice at the inlet of inlet casing and increasing inlet distortion 4% higher, the adiabatic efficiency of blade section became 1 % higher. A new correlation between inlet distortion and adiabatic efficiency of blade section at the rated flow rate was derived based on compressor-in-parallel model and fitted to the test results. Overall adiabatic efficiency of full scale compressor was predicted 90.2% based on the test results of efficiency and Reynolds number correlation, which was close to 89.7% that was predicted by test calibrated design and CFD codes, which satisfied the design value 89.0 % of the compressor for GTHTR300.
Shiina, Yasuaki; Takizuka, Takakazu; Kasahara, Seiji
Nihon Genshiryoku Gakkai-Shi, 48(2), p.58 - 59, 2006/02
no abstracts in English
Shiina, Yasuaki; Takizuka, Takakazu; Kasahara, Seiji
Nihon Genshiryoku Gakkai-Shi, 46(12), p.862 - 863, 2004/12
no abstracts in English
Kunitomi, Kazuhiko; Katanishi, Shoji; Takada, Shoji; Takizuka, Takakazu; Yan, X.; Kosugiyama, Shinichi
JSME International Journal, Series B, 47(2), p.261 - 267, 2004/05
The GTHTR300 aiming at electric generation with its thermal efficiency of 46 % is a safe and economically competitive HTGR in 2010s. A helium gas turbine system connected with the reactor is designed based on existing technologies developed for fossil gas turbine systems. However, there are some uncertainties in performance of a helium gas compressor, electric magnetic bearings and control system. In order to confirm these technical uncertainties, a 1/3 scale model of the compressor and 1/3 scale magnetic bearings will be manufactured and tested in the simulated condition of the GTHTR300. This paper describes R&D plans focusing on the 1/3 scale compressor model test as well as unique design features of the GTHTR300.
Kosugiyama, Shinichi; Takei, Masanobu; Takizuka, Takakazu; Takada, Shoji; Yan, X.; Kunitomi, Kazuhiko
Nihon Genshiryoku Gakkai Wabun Rombunshi, 2(4), p.532 - 545, 2003/12
no abstracts in English
Takada, Shoji; Takizuka, Takakazu; Kunitomi, Kazuhiko; Kosugiyama, Shinichi; Yan, X.; Matsumoto, Iwao*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 2(4), p.525 - 531, 2003/12
no abstracts in English
Takada, Shoji; Takizuka, Takakazu; Kunitomi, Kazuhiko; Yan, X.; Tanihira, Masanori*; Itaka, Hidehiko*; Mori, Eiji*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 2(3), p.291 - 300, 2003/09
no abstracts in English
Kosugiyama, Shinichi; Takizuka, Takakazu; Kunitomi, Kazuhiko; Yan, X.; Katanishi, Shoji; Takada, Shoji
Nihon Genshiryoku Gakkai Wabun Rombunshi, 2(3), p.319 - 331, 2003/09
no abstracts in English
Takada, Shoji; Takizuka, Takakazu; Kunitomi, Kazuhiko; Yan, X.; Minatsuki, Isao*
Dai-31-Kai Gasu Tabin Teiki Koenkai Rombunshu, p.55 - 60, 2003/06
no abstracts in English
Takada, Shoji; Takizuka, Takakazu; Kunitomi, Kazuhiko; Yan, X.; Katanishi, Shoji; Kosugiyama, Shinichi; Minatsuki, Isao*; Miyoshi, Yasuyuki*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 1(4), p.341 - 351, 2002/12
no abstracts in English
Kunitomi, Kazuhiko; Katanishi, Shoji; Takada, Shoji; Takizuka, Takakazu; Nakata, Tetsuo; Yan, X.; Takei, Masanobu; Kosugiyama, Shinichi; Shiozawa, Shusaku
Nihon Genshiryoku Gakkai Wabun Rombunshi, 1(4), p.352 - 360, 2002/12
no abstracts in English
Kosugiyama, Shinichi; Takada, Shoji; Katanishi, Shoji; Yan, X.; Takizuka, Takakazu; Kunitomi, Kazuhiko
JAERI-Tech 2002-088, 70 Pages, 2002/11
JAERI-Tech-2002-088.pdf:5.21MB
no abstracts in English
Kurata, Yuji; Takizuka, Takakazu; Osugi, Toshitaka; Takano, Hideki
Journal of Nuclear Materials, 301(1), p.1 - 7, 2002/02
Times Cited Count：11 Percentile：58.11(Materials Science, Multidisciplinary)no abstracts in English
Takada, Shoji; Takizuka, Takakazu; Kunitomi, Kazuhiko; Yan, X.; Katanishi, Shoji; Kosugiyama, Shinichi; Shiozawa, Shusaku
Nihon Kikai Gakkai Dai-8-Kai Doryoku, Enerugi Gijutsu Shimpojiumu Koen Rombunshu, p.189 - 192, 2002/00
no abstracts in English
Katanishi, Shoji; Kunitomi, Kazuhiko; Takada, Shoji; Nakata, Tetsuo; Takizuka, Takakazu; Shiozawa, Shusaku
Nihon Kikai Gakkai Dai-8-Kai Doryoku, Enerugi Gijutsu Shimpojiumu Koen Rombunshu, p.185 - 188, 2002/00
no abstracts in English
Kunitomi, Kazuhiko; Katanishi, Shoji; Takada, Shoji; Takizuka, Takakazu; Yan, X.; Nakata, Tetsuo; Takei, Masanobu; Kosugiyama, Shinichi; Shiozawa, Shusaku
Nihon Kikai Gakkai Dai-8-Kai Doryoku, Enerugi Gijutsu Shimpojiumu Koen Rombunshu, p.181 - 184, 2002/00
no abstracts in English
