著者

段 智久 大石 直己 千田 二郎 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.60, no.577, pp.3192-3197, 1994-09-25 (Released:2008-03-28)

参考文献数

4

被引用文献数

1 6

---

In the experiments presented, a single diesel spray of n-tridecane was injected for a certain duration through a hole-type nozzle into a quiescent atmosphere at room temperature at high pressure. The experimental variables were nozzle hole dimensions such as the hole diameter dn, the hole length ln and the hole offset between the nozzle axis and the hole axis, and the nozzle needle lift, in order to assess the turbulent flow field inside the nozzle, and the other was the back pressure, in order to examine the effect of the ambient gas properties, especially its kinematic viscosity. The macroscopic spray structures were observed by using instantaneous photography and a high-speed video camera system. Furthermore, the microscopic structure was observed by meant of scattering photography of fuel droplets taken by the laser light sheet of a pulsed ruby laser, and the quantitative 2-D image of fuel concentration in the cross section of the spray containing its central axis was obtained by the image processing. From the experiments, the variation in the spray cone angle with the needle lift is promoted by the turbulence in the sac volume, and spray angle is closely related to the ambient kinematic vincosity.

著者

永野 翔大 ネメシュ ローランド 藤本 元 會田 宏

出版者

日本コーチング学会

雑誌

コーチング学研究 (ISSN:21851646)

巻号頁・発行日

vol.30, no.2, pp.109-123, 2017-03-20 (Released:2019-09-02)

参考文献数

42

被引用文献数

5

---

The purpose of this study was to obtain useful knowledge for constructing new Japanese Long-Term Athlete Development Program by a text mining analysis. Subjects were comprised of four countries, Germany, Hungary and Denmark as world top class, plus Japan. The main results were as follows: 1) Germany: Based on their physical advantage, Germany aimed to improve predictive ability by nurturing their decision making in the speed. So that they could acquire the ability to take an initiative in a game. 2) Hungary: Hungry aimed to encourage their physical strength as most important concept to improve team tactics which focuses on group combinations. 3) Denmark: Denmark aimed to improve predictive ability through trainings in numerically unequal situation at early stage. 4) Japan: Japan set the categories in broad age ranges and aimed to bring up from sensory play to intentionally play to reach worldʼs top level.     When creating new Japanese Long-Term Athlete Development Program, these results suggest that necessities of drafting instruction contents and instruction plan which can achieve “Japanese Total Mobility”.

著者

千田 二郎 柴田 一郎 段 智久 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.63, no.613, pp.3173-3178, 1997-09-25 (Released:2008-03-28)

参考文献数

8

被引用文献数

1 2

---

This study investigates the atomization mechanism of fuel spray dissolved in noncondensable gas, such as N2, CO2. The fuel spray was injected at room temperature and in an atmospheric pressure field through a diesel-hole-type nozzle. In this paper, N2 gas was dissolved into diesel fuel, n-tridecane, under several pressurized conditions using a gas bubbling method in a constant volume vessel. This fuel, with high gas solubility, was injected under several injection pressures using an accumulated injection system designed by the authors. It was found that the dissolved gas separated into gas bubbles like gas cavitation phenomena under the atmospheric field. The change in spray patterns caused by the gas solubility is discussed using photographs of the patterns.

著者

藤本 元啓

出版者

崇城大学

雑誌

崇城大学紀要 = Bulletin of Sojo University (ISSN:21857903)

巻号頁・発行日

vol.46, pp.37-55, 2021

---

崇城大学では、2019年度から初年次教育「SOJO基礎」を起点として理工系専門教育とを連動し、大学と産業界とを接続する学修プログラム「SOJOプロジェクト教育」を開始した。初年次生では専門的知識を必要としないアイデア解決型のPBL型学修を反復し、2年次以降に学科や企業等の提供による理工学・実社会の現実的な問題に取り組み、学年に応じた専門基礎的なアイデアをもって解決を目指す。学部でのこの教育が修士課程の長期のコーオプ教育につながり、さらには博士課程の産学連携を生み出す土壌となる。これは従来の伝統的な大学教育(教える)からの脱却を目指す教育プログラムのひとつで、本学が目指す「学生の自主的、創造的な学修姿勢」を培う新しい教育体系である。この組織的な取り組みにより、学生が主体的学修へと転換し、知識・技能を実際に活用して徐々に高品質の成果物をつくる契機となることに期待している。また協力企業からは「知識修得だけではなくチーム活動に焦点を当てたカリキュラムの重要性」「企業と大学の協力は不可欠」「国際競争力向上のためには学生の人材育成は必要」など、大方の賛同を得ている。

著者

高岸 佐代 高橋 知宏 段 智久 千田 二郎 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.65, no.631, pp.1128-1133, 1999-03-25 (Released:2008-03-28)

参考文献数

9

被引用文献数

2 1

---

The characteristics of combustion process in internal combustion engines are affected by mixing process between the injected fuel and the ambient gas. Therefore, it is necessary to understand the flow field in diesel fuel sprays. In this study, a single spray was injected into a quiescent atmosphere with room temperature at high pressure through a single hole nozzle for simplification. To discuss the flow field in diesel sprays, structure of the spray was visualized by laser light sheet method. And, it was revealed that the vortex structure inside the spray affects the classification of droplet particles by taking microscopic photographs of the droplets with high resolution film. And applying PIV method into the spray photography, both the formation of meandering structure of the spray mainstream and the ambient gas entrainment process are clarified.

著者

段 智久 高岸 佐代 大石 直己 千田 二郎 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.62, no.597, pp.2079-2085, 1996-05-25 (Released:2008-03-28)

参考文献数

15

被引用文献数

7 8

---

In the experiments presented here, a single diesel spray of n-tridecane was injected for a certain duration through a hole-type nozzle (ln/dn=1.1mm / 0.2mm) into a quiescent high pressure atmosphere at room temperature. We used the same amounts of fuel injection for each injection pressure and the same ambient gas density field for all injection experiments including tests of the effect of changing the ambient gas. The macroscopic spray structures were observed by instantaneous photography and using a high-speed video camera system. Furthermore, the microscopic structure was observed by means of laser light-scattering photography, fuel droplet distribution was measured using the laser light-sheet of a pulsed Nd-YAG laser, and the mean diameter of the drop was obtained through image processing by the laser extinction method. This study revealed that the diesel spray consisted of a number of large vortices, which was considered to be the coherent structure. With high ambient gas viscosity, the fuel droplet became smaller. It was also found that a large vortex existed at the tip of the spray.

著者

段 智久 高岸 佐代 大石 直己 千田 二郎 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.62, no.599, pp.2867-2873, 1996-07-25 (Released:2008-03-28)

参考文献数

14

被引用文献数

2 5

---

This study deals with the effect of the viscosity of the ambient gas on the atomization process of a diesel spray. The liquid fuel is injected through a single-hole nozzle (ln/dn=0.75 mm/0.25 mm)with the injection differential pressure of 16.2 MPa inside a constant-volume vessel under a high-pressure field at room temperature. In practical combustion chambers of diesel engines, the viscosity of the ambient gas varies mainly with its temperature. In this experiment, various gases (CO2, N2, Ar, Ne, and Ar+Ne) were utilized for the ambient atmosphere in order to change the ambient gas viscosity. The vaporization of fuel drops was negligible. This study, revealed that the higher the viscosity, the more the spray spreads in the radial direction, thus the spray angle increased and tip penetration decreased. The droplets became smaller and were distributed in the inner region of the cold-state diesel spray under high ambient viscosity conditions. Further more, it was found that processes of ligament formation in the liquid jet and initial atomization were affected by kinematic viscosity ratio between the liquid fuel and ambient gas, and the spray dispersion and mixing process in the downstream region was affected only by the ambient gas kinematic viscosity.

著者

藤本 元 Roland Nemes

出版者

一般社団法人 日本体育学会

雑誌

日本体育学会大会予稿集

巻号頁・発行日

vol.65, 2014

著者

草野 茂之 段 智久 千田 二郎 藤本 元

出版者

一般社団法人日本機械学会

雑誌

日本機械学会論文集. B編 (ISSN:03875016)

巻号頁・発行日

vol.65, no.630, pp.804-811, 1999-02-25

参考文献数

10

被引用文献数

2

---

In this study, new models on the new droplet evaporation taking account of the droplet surface temperature related to the modified Spalding model, on the ambient temperature and the mass fraction at the infinite-point was proposed and incorporated into KIVA-II code. These models were compared and reviewed with the droplet evaporation model of KIVA-II original code in relation to the standard Spalding model. As a results, it is found that the calculated results of droplet evaporation by new model agree well with actual phenomena.

著者

草野 茂之 段 智久 千田 二郎 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.65, no.630, pp.804-811, 1999-02-25 (Released:2008-03-28)

参考文献数

10

被引用文献数

3 4

---

In this study, new models on the new droplet evaporation taking account of the droplet surface temperature related to the modified Spalding model, on the ambient temperature and the mass fraction at the infinite-point was proposed and incorporated into KIVA-II code. These models were compared and reviewed with the droplet evaporation model of KIVA-II original code in relation to the standard Spalding model. As a results, it is found that the calculated results of droplet evaporation by new model agree well with actual phenomena.

著者

永野 翔大 藤本 元 會田 宏 Hajime FUJIMOTO Hiroshi AIDA Nagano Shota

出版者

筑波大学体育センター

雑誌

大学体育研究 = Bulletin of Sport and Physical Education Center, University of Tsukuba (ISSN:03867129)

巻号頁・発行日

vol.39, pp.19-28, 2017-03

著者

千田 二郎 柴田 一郎 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.63, no.613, pp.3179-3186, 1997-09-25 (Released:2008-03-28)

参考文献数

20

---

In this paper, propose a new fuel injection system using diesel fuel dissolved in liquefied CO2. The system has the capability of reducing both NOx and soot simultaneously. This concept strives to improve the atomization of fuel spray by flash boiling liquefied CO2 gas. Moreover, it is possible to control the combustion system, for instance, and internal EGR effect is produced by the separated CO2 gas. In this paper, the characteristics of diesel spray of the fuel dissolved with liquefied CO2 were investigated using several optical measurements and the variance of CO2 molar fraction, ambient pressure and ambient density under room-temperature conditions. The spray characteristics were revealed using analysis in chemical thermodynamics. The atomization and dispersion of a free spray composed of fuel dissolved in liquefied CO2 are much better than those of normal diesel fuel oil, due to the flash boiling process in the relatively low pressure field.

著者

川野 大輔 千田 二郎 和田 好充 藤本 元 石井 素 鈴木 央一 後藤 雄一 小高 松男

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.70, no.696, pp.2213-2219, 2004-08-25 (Released:2011-03-03)

参考文献数

20

被引用文献数

1

---

Original KIVA code cannot take account for the spray and combustion processes of multicomponent fuels. Therefore, it is necessary to produce the sub-models for multicomponent fuel using KIVA code. In this study, the modeling of detailed physical properties and evaporation process for multicomponent fuel was conducted. In addition, the effects of fuel composition in multicomponent fuel on vapor distribution, spray tip penetration, vapor mass and evaporation rate, and sauter mean diameter were numerically investigated by using KIVA 3 V code with this multicomponent fuel spray model. From the numerical results, the spray characteristics of multicomponent fuel varied with a change in mixing fraction in multicomponent fuel. Especially, the evaporation of multicomponent fuel was not necessarily improved, even if much amount of high volatility fuel was mixed in the multicomponent fuel.

著者

千田 二郎 錦織 環 北條 義之 塚本 時弘 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.60, no.578, pp.3556-3562, 1994-10-25 (Released:2008-03-28)

参考文献数

23

被引用文献数

2 4

---

This paper presents the model analysis of atomization and vaporization process in a flash boiling spray based on the experimental results. Two kinds of liquid fuel, n-Pentane and n-Hexane, are injected into quiescent gaseous atmosphere at room temperature with low pressure through a pintle-type injector. Then, in flash boiling spray region where the back pressure is below the saturated vapor pressure of fuel, the bubble nucleation process due to flash boiling is modeled by the nucleation rate equation. Furthermore, fuel vaporization process is assessed by considering bubble growth calculations of vapor cavitation phenomena and fuel evaporation due to heat transfer process. Accordingly, we could estimate quantitatively the transient changes in bubble diameter and vapor mass fraction inside the spray for each back pressure condition.

著者

千田 二郎 浅井 崇胤 川口 文悟 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.65, no.632, pp.1459-1466, 1999-04-25 (Released:2008-03-28)

参考文献数

15

---

The new injection system by using mixed fuel dissolved with liquefied CO2 was proposed in this paper. Liquefied CO2 was mixed into n-tridecane under pressurized state in order to promote the spray atomization and evaporation due to the effect of the flash boiling phenomena in fuel injection, and to control the combustion process due to the effect of internal EGR effect of CO2 gas. Therefore, the simultaneous reduction of soot and NOx cas be achieved effectively by use of this injection system. In this paper, the characteristics of diesel fuel spray dissolved with liquefied CO2 were investigated quantitatively by means of several optical measurements. And the spray characteristics were revealed by the analysis of chemical thermodynamics. As a result, the atomization of this fuel is promoted due to the flash boiling much more than n-tridecane as the reference of the normal fuel and the spray structure is highly diHerent from that of the normal fuel.Moreover, thenumerical analysis for the atomization and the vaporization process wan carried out based on the flash boiling spray models.

著者

千田 二郎 檜垣 智大 高橋 秀和 高木 靖雄 足立 正之 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.65, no.640, pp.4106-4112, 1999-12-25 (Released:2008-03-28)

参考文献数

12

被引用文献数

2 1

---

In previous multi-dimensional modeling on spray dynamics and vapor formation, single component fuel with pure substrance has been analyzed to assess the mixture formation process. Then it shold be expected that the evaporation process could be performed for the multi-component fuel such as actual Gasoline and Diesel gas oil. In this study, vapor liquid equilibrium prediction was conducted for multi component fuels such as 3 and 10 components mixed solution with ideal solution analysis and non ideal solution analysis. And the computation of distillation characteristics was conducted for the steady state fuel conditions to understand the evaporation process. As a result, calculated distillation characteristics is consistent well with experiment results. Further the vapor concentration was measured for the analysis of the binary fuel spray using IR absorption measurement method.

著者

千田 二郎 錦織 環 北條 義之 塚本 時弘 藤本 元

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.60, no.578, pp.3551-3555, 1994-10-25 (Released:2008-03-28)

参考文献数

13

被引用文献数

3

---

In this study, the influence of the flash boiling phenomenon on the fuel spray characteristics was in vestigated using both experiments and model analysis. Pure liquid fuel of n-Pentane or n-Hexane is injected into a vessel under quiescent gaseous atmosphere at room temperature through a pintle-type injector. Fuel sprays are observed by taking photographs for variation of ambient back pressure. In particular, changes in spray characteristics with back pressure are examined in detail. The results show that the saturated vapor pressure of fuel is the most significant factor and the spray characteristics can be varied with the pressure difference between the back pressure and saturated vapor pressure. Furthermore, flow field of the fuel inside the nozzle is estimated with regard to bubble initiation inside the film flow.

著者

千田 二郎 山田 耕司 藤本 元 三木 英雄

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 B編 (ISSN:03875016)

巻号頁・発行日

vol.53, no.485, pp.176-182, 1987-01-25 (Released:2008-03-28)

参考文献数

19

被引用文献数

1 2

---

The purpose of this paper is to obtain fundamental information concerning the heat transfer process and breakup behavior characteristics of individual small droplets impinging upon a hot surface. A uniform sized water droplet array at room temperature under atmospheric pressure was produced by the vibratory method to impinge upon a heated flat copper surface. And then, heat transfer from a surface to the droplets is assessed by a transient technique. Further, the deformation and the breakup behavior owing to the impingement of the droplet is observed by means of a drum camera recording high-speed microscopic photographs. Heat transfer effectiveness in a low temperature range of less than 125°C decreases as droplet impingement frequency increases because of interference between the impinging droplet and the remaining liquid film on a surface. It is possible that heat transfer per droplet is transfermed into a heat transfer coefficient by use of droplet residence time and film contact area on a surface. And Variations in the heat transfor coefficient for a droplet array with surface temperature are measured by difference calculus of the one dimensional unsteady heat conduction equation.