著者

南部 健一

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.73, no.726, pp.395-398, 2007-02-25

著者

佐藤 久雄 千島 美智男 細川 成之

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.72, no.718, pp.1456-1464, 2006-06-25

参考文献数

5

被引用文献数

1

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In order to increase the safety and reliability of ropeway systems, it is extremely important to improve windproof performance of carriers since the excessive swing of the carrier by wind may lead to a serious accident such as a collision with the columns. As the first step of studying improvement of windproof performance of ropeway carriers, this paper presents analysis results of accidents due to wind and results of wind tunnel experiments of real carriers. Analysis results of accidents clarified features of ropeway accidents due to wind. Results of wind tunnel experiments showed aerodynamic characteristics of two typical monocable carriers.

著者

吉川 大雄 菱沼 孝夫 近久 武美 早坂 厚

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.68, no.665, pp.218-223, 2002-01-25

参考文献数

12

被引用文献数

2

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The objective of this study was to estimate the optimization of fuel cell electric vehicle systems by the driving simulation that we developed. The results of the driving simulation showed the power of fuel cell, battery and motor for a 1 500 cc class sedan is 12, 18 and 15 kW at the condition of 10-15 mode of the minimum fuel consumption. The fuel consumption of the series driving system of FCEV was more than the parallel because of the heavier vehicle weight of the series compared to the parallel. The numerical analysis showed that the FCEV performance is affected by the regenerative brake and the fuel consumption of the FCEV with the regenerative brake systems is 23% less than without them.

著者

影目 樹亮 大島 孝昌 中山 正人 伊藤 衡平 恩田 和夫

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.70, no.689, pp.223-228, 2004-01-25

参考文献数

10

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The nickel/metal hydride battery (Ni/MH) has been developed as a power source for the hybrid electric vehicle (HEV) and the pure electric vehicle (PEV). But the large battery with heavy duty cycle by more rapid charge and discharge than today's is desirable for the diffusion of HEV and PEV. Therefore the thermal behavior of Ni/MH battery must be understood precisely for the battery size enlargement and its performance improvement. In this report the thermal behavior of small Ni/MH battery during rapid charge and discharge cycle has been studied numerically and experimentally by considering the entropy changes by electrochemical reactions, the endothermic reaction by hydrogen occlusion to MH, the exothermic reaction by side reaction, the heat generation by overpotential and the heat transfer to the ambient air. The calculated cell temperature agrees well with the measured under both the charge and discharge cycles below the rated current, but the calculated is larger than the measured above the rated current.

著者

橋本 健 古畑 朋彦 新井 雅隆

出版者

日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.72, no.721, pp.2323-2329, 2006-09-25

参考文献数

8

被引用文献数

1

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Six-stroke diesel engine proposed here has six processes in one cycle, i.e. intaka, 1st compression, 1st combustion, 2nd compression, 2nd combustion and exhaust. By the effect of direct EGR in the 2nd combustion process, NO concentration could be expected to decrease. However, by a weak mixing in the 2nd combustion process, much soot was exhausted and NO concentration was hardly decreased compared with the conventional four-stroke diesel engine. To improve the fuel/air mixing at the 2nd combustion process, high pressure injection with common rail system was applied to the engine. As the result, NO concentration was increased owing to the increase of premixed combustion of 1st combustion process, although soot was reduced. Therefore, the 1st injection timing was extremely advanced to control the 1st combustion process. It changed 1st combustion process into HCCI-like combustion, and NO concentration was greatly decreased. Moreover, soot was reduced with no increase of NO concentration in the 2nd combustion process. As the result, trade-off curve of NO and soot was improved compared with the conventional four-stroke diesel engine. But CO concentration was increased.

著者

阿部 豊 新井 崇洋

出版者

日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.71, no.702, pp.658-665, 2005-02-25

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Spontaneous vapor explosion can occur when a layer of the high temperature molten material lies on the water pool or on the moisture floor. This is so-called base-triggered vapor explosion. The base-triggered vapor explosion is supposed to occur in the case of a severe accident in various industrial facilities. It is very important to clarify the occurrence condition and possibility of the base-triggered vapor explosion from the viewpoints of the prediction and the prevention of the vapor explosion. In order to evaluate the occurrence conditions and to clarify the micro-mechanism of the base-triggered vapor explosion, the experimental apparatus to observe the base-triggered vapor explosion from the bottom of the floor to above is designed and constructed. The experiments using U-Alloy95 as a simulant material are conducted. Consequently, the microscopic behavior at the interface between the molten material and water can be observed in detail with this experimental apparatus. The interfacial behavior of the molten material is quantitatively evaluated by the PIV analysis and the digital auto-colrrelation method with the experimental results. The blowout velocity of the molten material at vapor explosion is evaluated from the visual data obtained on the experiment. The generated pressure at the vapor explosion is estimated by using the blowout velocity. In addition, occurrence condition of the base-triggered vapor explosion is evaluated with the thermal interaction zone (TIZ) theory.

著者

太田 有 大田 英輔 斎藤 純夫

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.68, no.671, pp.2056-2063, 2002-07-25

参考文献数

14

被引用文献数

1

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Active cancellation of noise source of higher-order blade-passing frequency noise, abbreviated to BPF noise, radiated from a centrifugal blower is conducted. The extents of noise sources of 2nd-and 3rd-order BPF components were determined by measuring a cross-correlation function between the data of the acoustic pressure measured at blower inlet and the pressure fluctuation on the scroll surface. The effective noise sources of these higher-order BPF components exist on the volute side surface of scroll relatively apart from the cut off apex, and vary irregularly with operating conditions of the blower. While the noise source of fundamental BPF lies on the vicinity of the cut off apex as usually expected. Oscillating the volute side surface of the cut off, i.e. the effective noise source of higher-order BPF components, directly by piezoelectric actuators, sound pressure level of higher-order BPF components can be reduced more than 15 decibels, and discrete tone disappears completely from power spectra of the blower radiated noise.

著者

辻 義之 宮地 圭 鈴木 孝裕 中村 育雄

出版者

日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.70, no.695, pp.1679-1686, 2004-07-25

参考文献数

17

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In a zero-pressure gradient turbulent boundary layer, the multi-point measurement by 24 ch I-probes is performed. The relation between coherent structures and logarithmic velocity profile is studied by way of proper orthogonal decomposition technique and the stochastic estimation. It is found that the existence of coherent structures are necessary condition for the universal velocity profile, however it is not enough. Small-scale motions are also necessary to realize the log-law profile. The probability density profile in the overlap region is studied, and as a result, the invariant assumption of PDF in relation to the coherent structure is obtained. It was also evaluated how the velocity fluctuation in the log-region is affected by the coherent structures.

著者

杉井 康彦 西尾 茂 岡本 孝司 中野 厚史 南山 求 新見 英幸

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.70, no.691, pp.701-706, 2004-03-25

参考文献数

18

被引用文献数

2

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Blood flow in microvessels, such as arterioles, capillaries and venules, whose diameter ranges from 5 to 50μm, is responsible for the maintenance of tissue and organ functions. The measurement of microvascular blood flow velocity with high measurement accuracy is essential for basic and clinical studies in the assessment of flow shear stress at the vascular wall in relation to substance exchange between blood and tissue. This paper aimed to evaluate the velocity field of blood flow in microvessels with high spatial and temporal resolution. By using micro PIV system, the velocity distributions of red blood cells flowing in rat mesenteric arterioles, including near the wall in the axisymmetric plane, were obtained. Ensemble averaged time-series of velocity profiles in the cross-sections were calculated for comparison. It was shown that the arteriole velocity profile was blunt in the center region of the vessel cross-section while it was steep in the near wall region.

著者

前田 太佳夫 鎌田 泰成 酒井 雄作 高原 直樹

出版者

日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.71, no.701, pp.171-176, 2005-01-25

参考文献数

5

被引用文献数

5

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This paper describes the measurement of the flow field around rotor blade. Three-bladed upwind rotor was tested in an open jet type wind tunnel. The rotor has a diameter of 2.4m. Flow field around rotor blade was measured with the use of two-dimensional LDV. The flow field was measured in x-y plane and z-y plane. The circulation around the blade sections were calculated by flow vectors around the rotor blade. The velocity vectors at optimum operation show a smooth flow around the blade and the bound vortex around blade cross-section seems to be persistent. On the other hand, the velocity vectors at stall condition demonstrate significant fluctuations in the near wake and separation on the blade suction side was observed. The circulation around blade span-wise section was calculated at the certain control volume. By the observation of flow field and calculated results of circulation, it seems that the flow is separated at the blade from middle-span region to tip region at stall condition. No separation was observed at the blade root region.

著者

坂本 健太郎 遠藤 小太郎 行本 正雄 武田 邦彦

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. B編 = Transactions of the Japan Society of Mechanical Engineers. B (ISSN:03875016)

巻号頁・発行日

vol.72, no.722, pp.2338-2345, 2006-10-25

参考文献数

24

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The amount of woody biomass resources in Aichi Prefecture and Toyone Village was estimated on the basis of theoretical and actual production efficiencies. Five factors should be considered at the steady production of reduced carbon from carbon dioxide by sunlight in woods. The ratio of leaf to forest area, the reflection of sunlight on leaf surface, the conversion efficiency from the light energy, efficiency of optical system, and of dark reaction are 0.70, 0.82, 0.24, 0.31, and 0.92 respectively. On the other hand, four factors are in the timber production stage. The energy consumption loss for the daily life of woods, the waste at the forest, the thinner woods to main cutting production, and the thinning are 0.50, 0.47, 0.435, 0.44, respectively. The total efficiency was calculated and the result was 0.0023. Furthermore, near fiscal year 2000, primary energy consumption in Aichi Prefecture is 1.48×10^9 GJ/year, so it is 2200 times than the present production amount and 300 times the best theoretical production amount.