-
原稿種別: 表紙
p.
Cover1-
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
-
原稿種別: 目次
p.
Toc1-
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
-
池内 房子, 坂本 弘志, 高井 和紀, 森谷 優, 小畑 芳弘
原稿種別: 本文
p.
2-3
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The response characteristics and suppression of flow-induced vibrations of rectangular prisms with various width-to-height ratios were experimentally investigated. The present study focused on rotary oscillation, which is one of flow-induced vibrations generated in a rectangular prism. In this paper, the response characteristics on elastically supported prisms were first examined in detail by free-vibration test. Next, flow-induced vibrations obtained by the free-vibration test were reproduced by forced-vibration test, and then the generation mechanism of flow-induced vibrations was examined on the basis of the visualized flow patterns, fluctuating pressure distributions of the surface of prism and characteristics of flow-induced vibrations by the flow control.
抄録全体を表示
-
高井 和紀, 坂本 弘志, 森谷 優, 小畑 芳弘
原稿種別: 本文
p.
4-5
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The generation mechanism and suppression of flow-induced vibration of rectangular prisms were experimentally investigated. The present study focused galloping of a square prism, which is one of flow-induced vibrations generated in a rectangular prism. The square prism having width to height ratio B/H=1.0 in which galloping starting spontaneously from rest can occur for 0.75<B/H<3.0,approximately, is adopted. At first, the response characteristics of a square prism are investigated on the free-vibration test. Next, the generation mechanism of galloping is discussed with the results of the forced-vibration test. The experimental results obtained in a wind tunnel showed that the galloping becomes divergent when work done by fluctuating lift is positive work.
抄録全体を表示
-
丹 国夫, 森谷 優, 坂本 弘志
原稿種別: 本文
p.
6-7
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Investigations on characteristics of flow and fluid forces acting on a circular cylinder with two tripping rods were carried out in a uniform flow at a Reynolds number of 5.5×(10)^4. The diameter of the tripping rod was chosen 0.08∿0.12 times of the cylinder. To obtain an optimum location of tripping rod for suppressing fluid forces, the position of the tripping rods were varied from 20°∿60° and fluid forces acting on the cylinder were measured systematically. From the result, it was found that the optimum location of the tripping rods were 30°∿40° based on the consideration of suppression of time-averaged and fluctuating fluid forces. In addition, the effect of tripping rods on flow structures and fluid forces are discussed in details based on surface pressure distributions, Strouhal numbers, surface oil- flow pattern, power spectrum distribution and flow visualization.
抄録全体を表示
-
島田 卓弥, 高山 晋一, 青木 克巳
原稿種別: 本文
p.
8-9
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
This paper describes the flow characteristics around a circular cylinder with arc type grooves. In this study, the cylinders with grooves form an arc with different depth of grooves are used. The number of grooves is thirty-two. Three pressure measurement holes inside the groove and one between the grooves are prepared in order to measure the surface pressure distribution on the cylinder. Drag and lift coefficient are calculated from the pressure distribution measured in the range of Reynols number Re=0.2×(10)^5∿1.8×(10)^5. From these experimental results, the variation of drag and lift coefficient toward the depth of grooves and Reynols number of the circular cylinder with grooves in uniform flow are developed.
抄録全体を表示
-
井出 篤幸, 高山 晋一, 青木 克己
原稿種別: 本文
p.
10-11
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
This paper is described on the flow characteristics around the rotating cylinder with arc type grooves. The lift and drag on a smooth cylinder and cylinders with arc type grooves in a uniform flow are measured within the Reynolds number range 0.2×(10)^5≤Re≤1.8×(10)^5 with 0 to 4000rpm rotation in a wind tunnel. For the smooth cylinder, lift thirst increases as the spin rate ratio increases. However, as the spin rate ratio further increases, the lift decreases, and then a negative lift occurs when spin rate ratio α=0.4 to 0.5. After the lift reaches the minimum value, it increases again as the spin rate ratio increases. In contrast, drag decreases until the spin rate ratio reaches 1.0 for the smooth cylinder. In the case of a circular cylinder with grooves lift, it simply increased without decrease against the spin rate unlike the case of a smooth cylinder. These phenomena were clarified through analysis of the distribution of average pressure around a rotating cylinder and visualization of the flow patterns around the cylinder by the spark tracing method.
抄録全体を表示
-
野中 政洋, 青木 克巳, 山口 清大
原稿種別: 本文
p.
12-13
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
This paper describes an experimental study on effect of dimple number on flying characteristics of golf ball. This study clarifies the flight characteristics of the stationary spheres to the number of dimples and the depth of dimple as the basis study of the flight characteristics of the golf ball. Therefore, the surface of sphere of 42.6mm in diameter arranges 184∿328 dimples regularly. And in the wind velocity in the range from 15m/s to 45m/s, it measured drag and lift of these spheres in 15m/s intervals. Then, it found that the number of dimples and the depth of dimple gave the drag characteristic a big influence after doing the comparison and the examination of the measurement data. And also, to observe a separation point of spheres, it experimented in the visualization by the oil film method and static pressure distribution.
抄録全体を表示
-
廣田 英治, 青木 克巳, 長瀬 二郎
原稿種別: 本文
p.
14-15
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
This paper is described on the aerodynamics characteristic to surface structure in sphere ball. This study is a basic research for optimum design of surface structure of the rubber-ball used in baseball. The balls used for experiment were used the ball of 3 kinds of surface structure such as smooth sphere, ball with the seam. Drag and Lift coefficient were measured and visualized in uniform flow in the Reynolds number range of 2.3×(10)^4∿1.6×(10)^5. From these experimental results, the difference between aerodynamic lift and drag for this surface structure of the ball were clarified. The flow pattern of the sphere circumference for each ball was confirmed by the visualization experiment.
抄録全体を表示
-
Alam Mahbub, M. Moriya, K. Takai, H. Sakamoto
原稿種別: Article
p.
16-17
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Wake characteristics and characteristics of switching flow behind two circular cylinders placed in side-by-side arrangement were investigated experimentally in a uniform flow at a Reynolds number of 5.5×(10)^4. In the bistable flow regime, T/D=0.2∿1.2 (T, spacing between the cylinders; D, diameter), when high/low-frequency mode switched to low/high-frequency mode, another short duration stable flow pattern (which can be termed an intermediate flow pattern) persisted in the intermediate time, in which the gap flow was oriented parallel to the free-stream flow and the Strouhal number was almost equal to that of a single cylinder. Wavelet analysis of velocity signals obtained from two hotwires corroborated the appearance of the intermediate flow pattern. In the case of synchronized vortex shedding and even in the intermediate flow pattern, a predominant in-phase synchronized vortex was found to shed.
抄録全体を表示
-
Alam Mahbub, M. Moriya, K. Takai, H. Sakamoto
原稿種別: Article
p.
18-19
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Fluid forces acting on two stationary circular cylinders in a side-by-side arrangement were investigated experimentally in a uniform flow at a Reynolds number of 5.5×(10)^4. For a spacing ratio of T/D<1.5 (T, spacing between the cylinders; D, diameter), the gap flow was biased to one side, resulting in the formation of a narrower wake behind one cylinder and a wider wake behind the other. Steady and fluctuating fluid forces acting on the cylinders were decomposed for the narrower wake and the wider wake flow patterns. For T/D>0.20,the action of lift forces on both cylinders was in an outward direction (repulsive); however, for T/D=0.10,the action of lift force on the cylinder associated with the narrower wake was inward and that on the other cylinder was outward. Steady drag and fluctuating fluid forces were comparatively higher for the narrower wake. For T/D=0.10∿0.20 and 1.2∿1.50,the mean drag induced by the narrower wake and the wider wake was greater than that of a single cylinder.
抄録全体を表示
-
下岡 彩子, 芝 邦明, 難波江 亮, 松尾 亮弘, 豊田 国昭, 三橋 龍一, 佐鳥 新, 永田 晴紀
原稿種別: 本文
p.
20-21
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The launching project of a hybrid rocket from Taiki Multi-purpose Aerospace Park has been conducted by the research groups in the universities in Hokkaido. In the plan, after the flight in outer space, the rocket is taken back using a parafoil-glider with of GPS (Grobal Positioning System). The present study deals with the development of the winged vehicle to obtain the basic materials of the parafoil-glider system.
抄録全体を表示
-
生越 健介, 青木 克巳
原稿種別: 本文
p.
22-23
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
This study is described on Induced characteristics for swirl number of a swirl type confined jet. When this study is advanced, it is very important the flow pattern accompanied by the swirling flow in a cylinder pipe is clarified. So in this report, three time mean velocity components of swirling flow in circular duct is measured using five-hole pitot probe when the swirling numbers are changing from 0.35 to 1.35 by the axial flow type swirler. Further, the flow visualization is carried out using a streamer and numerical analysis and the flow patterns become clearer. From these results, the present study clarifies the location, size and shape of recirculation zone, eye of vortex and sub-recirculation zones for the swirling numbers.
抄録全体を表示
-
長山 敏之, 白濱 芳朗
原稿種別: 本文
p.
24-25
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The behaviour of vortices in a two-dimensional jet was investigated by the feedback excitation using the fluctuating of Vortical signal given phase-shift of the vortical structure. The experiment were carried out at exit velocity of 10m/sec and the Reynolds number is 1.42×(10)^4 based on the nozzle height. In this experiment, the excitation signal intensity u'/Ueo is fixed on 0.04. The power spectrum densities of the velocity fluctuation were measured along the jet center line. The result suggests the phase-shift of feedback excitation signal is the manipulation of vertical structures in a two-dimensional jet.
抄録全体を表示
-
河原 考司, 森 隼人, 平元 理峰, 豊田 国昭
原稿種別: 本文
p.
26-27
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The combined probe consisting of X-type hot-wire and pressure probes was used to measure velocity and fluctuating static-pressure simultaneously in a circular jet. The jet was excited at the interaction mode where the stable interaction of vortices was generated. Using the data, we discussed the relation between the large-scale vorticex motions and each term of turbulent energy equation. The results suggest that the vorticex motions are closely related to turbulent energy transport.
抄録全体を表示
-
風間 俊治, 藤原 満, 後藤 達也, 山口 惇
原稿種別: 本文
p.
28-29
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The behavior of cavitating jets and the intensity of cavitation erosion were correlated experimentally using the cavitating jet apparatus. The cavity-clouds of the jets were observed and recorded with video cameras, the existence-probability distributions of the clouds were obtained by picture processing techniques, and in parallel the cavitation erosion test was performed. Tap water or ISO VG 32 hydraulic fluid was alternatively used at 40±1 ℃. The upstream and down pressures were specified as 10 MPa and 0.1 to 0.3 MPa respectively. The stand-off distance was varied from 7.5 to 3.5 mm. The specimens were made of aluminum alloy, whose diameter was 15 mm. The specimen was eroded severely at a specific probability region; As the downstream pressure decreased, the range of the jet lengthened and the mass loss increased; In comparison with the oil-jet, the water-jet reached at the great distance and eroded the specimens substantially.
抄録全体を表示
-
三谷 將之, 荒川 源之進
原稿種別: 本文
p.
30-31
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Many Pitot-static Tubes were tried to make of Empty Cans and Straws. The Aluminium Empty Can is 66mm in diameter and 118mm in length, and one size of Steel Empty Can is 55mm in diameter and 96mm in length, the other size is 66mm in diameter and 96mm in length. The Straw is 6mm in diameter and 210mm in length. Specific characteristics of these Pitot-static Tubes were investigated by changing of static pressure hole's diameter and distance from Tube's tip. In the result, these characteristics were same. Furthermore, coefficients of these Pitot-static Tubes were obtained by the experiments on the test Pitot-static Tubes with wood stay and brass pipe stay. When length of Empty Can are 96mm and stay is brass pipe, a coefficient of Pitot Tube is 0.99,and when length of Empty Can are 96mm and stay is wood, it is 0.83. These test Pitot-static Tubes with both wood stay and brass pipe stay were known to use the same of standard Pitot-static Tube in either case. As a result of these experiments, it is known that Pitot-static Tubes with wood stay are better than those with brass pipe stay for teaching materials of pupils.
抄録全体を表示
-
石川 仁, 武田 靖
原稿種別: 本文
p.
32-33
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
A Ultrasonic Velocity Profile (UVP) measurement is a novel method, which obtains the velocity profile instanteneously. The UVP method is based on the pulse ultrasonic echography. Ultrasonic pulse is emitted from the transducer and reflected from the surface of the particle in flow. The echo, received by the transducer, contains the velocity profile information. This method has the many advantages comparing with the conventional techniques. In this paper, we introduce principal of the UVP method and an example of its application to the internal flow of the rotating cylinder, exhibiting its validity in analyzing the spatiotemporal velocity field.
抄録全体を表示
-
難波 利行, 大窪 智行, 柏熊 直哉, 武田 靖, 石川 仁, 森 治嗣
原稿種別: 本文
p.
34-35
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Seeding tracer is one of the important problems, when we use UVP. We have developed following three types of bubble generators to provide well-seeded condition for measuring velocity profile, 1) venturi tube type, 2) capillary tube type, 3) hydrogen production by electrolysised water. Especially a ventyuri tube type is expected to generate more favorite bubbles in terms of size and quantity than other two types.
抄録全体を表示
-
田坂 裕司, 米倉 賢午, 工藤 陽市, 但田 憲彦, 武田 靖, 石川 仁
原稿種別: 本文
p.
36-37
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The natural convection induced by internal heating was studied. In order to clarify convective patterns in this phenomenon, we analyzed stability of fluid layers for various profiles of heat generation, H(z). As the result, the influence of the shape of the heat distribution upon the convective pattern was clarified.
抄録全体を表示
-
米倉 賢午, 田坂 裕司, 工藤 陽市, 但田 憲彦, 武田 靖, 石川 仁
原稿種別: 本文
p.
38-39
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The natural convection induced by internal heat generation was studied experimentally. We realized internal heat generation by passing electric current through the ionic fluid. The convective flow patterns were visualized by using kalliroscope. And also the difference from those observed in the Benard configuration was clarified qualitatively.
抄録全体を表示
-
河合 秀樹, 高橋 洋志
原稿種別: 本文
p.
40-41
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Rotary filter, which avoided the cake sedimentation in the solid-liquid separation by Taylor vortex, was devised. The aspect ratio is less than 3 in the vortex generator, and the effect of the top and bottom boundary edge is not negligible. The alumna particle of 100μm was used as removed material as well as the tracer for the flow visualization. Vortex mode in the test of the rotational filter was the normal 2 cell mode, and the penetration flow rate was constantly to be 180ml/min. Reynolds number is varied from 100 to 600. Cake amount of sediment on the filter surface greatly decreased in Re>500,it remarkably observes the effect of the Taylor vortex.
抄録全体を表示
-
安永 勇一郎, 岩本 順二郎
原稿種別: 本文
p.
42-43
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
When the pressure ratio across the convergent nozzle exceeds the critical pressure ratio (1.893 for air), the jet becomes underexpanded. With the flat plate placed numerically in the jet the so-called "plate shock wave" appears in the front of the plate. It's essential to pursue the factor of this shock wave in detail. In the present study such flow field is visualized and the pressure distribution on the plate is measured in order to make clear the behavior of the plate shock wave and the flow pattern of the impinging jet. In the study, then, the flow field was cleared by using the experimental equipment which modeled the exhaust jet stream on the rocket or a vertical short take-off and landing aircraft.
抄録全体を表示
-
木村 敦典, 岩本 順二郎
原稿種別: 本文
p.
44-45
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The detail of pulsating flow typically seen in the exhaust system of four-cycle internal combustion engine was both experimentally and numerically simulated and investigated. It is extensively known that, as the result of non-linearity of compression wave propagating through the exhaust pipe, it leads to shock wave generation. Therefore, in the present study a special attention was paid in order to make the relationship of the flow field with the noise generation clear. In particular, the experiment was conducted under various conditions, with respect to the speed of engine. It became evident that characteristic of the flow field was strongly dependent on behavior of the compression wave generated by opening of exhaust valve. The change in gradient of the compression wave, especially, has great influence on the change in the flow field when the pulsating flow through the exhaust pipe discharges from the pipe end. This paper describes how and where the noise sources appear and the detail of pulsating flow associated with speed of engine.
抄録全体を表示
-
葛尾 武志, 杉山 弘, 溝端 一秀, 辰己 薫, 丸山 量平
原稿種別: 本文
p.
46-47
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
In order to clarify characteristics of supersonic intakes for ramjet engines, flow structure around and through a small external-compression rectangular intake model with double ramps designed for Mach number 1.9 was investigated experimentally using a vacuum-type wind tunnel and a set of measurement methods composed of colored schlieren photography, laser doppler velocimetry, and mercury manometry. A critical operation, where shocks induced by ramps attach to the leading edge of the cowl, was attained. A flow plug installed on the downward edge of the intake enables monotonous compression through a shock train caused by shock-boundary layer interaction.
抄録全体を表示
-
福田 浩一, 杉山 弘, 溝端 一秀, 広島 敬之, 孫 立群, 東条 啓
原稿種別: 本文
p.
48-49
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
To investigate the supersonic flow phenomena related to internal and external flows of high pressure gas pipeline systems, air breathing engines and space planes, a supersonic wind tunnel (pressure vacuum type, Mach4.0 and 2.0) was designed and constructed in Muroran Institute of Technology. This report describes an experimental study on the shock wave/boundary layer interaction (pseudo shock wave, or PSW) in a rectangular duct, using the supersonic wind tunnel. The PSW was visualized by schlieren photography. Detailed distribution of velocity in the PSW was measured by particle image velocimetry (PIV). Boundary layer separation after the first shock wave of the PSW occurred more severely on one of the upper and lower walls than on the other, producing an asymmetric flow field. Deceleration of the core flow around the centerline of the duct was small.
抄録全体を表示
-
大谷 清伸, 杉山 弘, 溝端 一秀, 小笠原 久敏
原稿種別: 本文
p.
50-51
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The large-amplitude shock wave propagation phenomena in air-bubbles/water mixtures were investigated using a two-phase shock tube. Effect of incident shock wave strength on shock wave pressure characteristics in mixtures and the precursor of shock wave are analyzed. It was found that the large-amplitude shock waves have high-frequency oscillation components and the precursor.
抄録全体を表示
-
戸倉 郁夫, 花岡 裕, 小川 徳哉, 佐藤 司
原稿種別: 本文
p.
52-53
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
An experimental study was conducted on the pressure drop for foam flow through a rectangular/circular pipe. Foam flow in a pipe was approximated by a model in which foam is lubricated by a thin layer of a Newtonian liquid (slip-layer) on the pipe wall. Indirect measurement of the slip-layer shows that its thickness depends on the flow velocity. Experimental equations for the slip-layer thickness were determined. A power-law equation with a yield shear-stress was used as the rheological equation for the foam flowing over the liquid-slip layer. Values of the parameters included in the equation were experimentally determined. Prediction of the wall shear stress for foam flow in a pipe can be possible by using these equations.
抄録全体を表示
-
大平 雪江, 松村 昌典
原稿種別: 本文
p.
54-55
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The purpose of this study is to reveal the effect of longitudinal vortex on production of Reynolds shearing stress in the wake. Reynolds shearing stress in the vortex street wake of a triangular prism and the turbulent wake of a grid body was measured in the case of approach flow containing longitudinal vortices or not containing them. As a result, it was found that longitudinal vortex in approach flow contribute to increase of Reynolds shearing stress very effectively in the turbulent wake. This result indicates one of good methods increased the turbulent mixture and diffusion.
抄録全体を表示
-
山澤 八朗, 花岡 裕, 前野 一夫, 井坂 秀治, 加藤 正友
原稿種別: 本文
p.
56-57
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The experimental study by using cryogenic wind tunnel has been conducted to estimate the location reattaching at the downstream of the backward-facing step and to clarify the unsteady phenomenon of the re-circulating flow. In the experiments, the fluid flow were visualized by use of a color schlieren method. The observation shows that the reattachment location over the backward-facing step ranges from X/H= 5 to 7 in the case of Mach number 0.08,where X/H indicates the ratio of the distance from the step face X to the step height H. On the other hand, in the case of Mach number 0.3,the observed results of reattachment point is X/H= 6 to 8. The fluctuation around the reattachment location may be taken to result that the unsteady "flapping" motion is reflected.
抄録全体を表示
-
畠沢 政保
原稿種別: 本文
p.
58-59
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Oscillatory flow in the thermoacoustic sound wave generator is described. Thermoacoustic phenomena are noteworthy, which is direct energy conversion from heat to work (sound wave) with no moving parts. Especially, oscillatory flow on the stack which set in the resonance tube plays an important role in thermoacoustic phenomena. Richardson's annular effect occurs and phase between pressure and velocity shifts in the vicinity of the tube wall. Some analyses of its flow are performed.
抄録全体を表示
-
讃岐 奏, 戸倉 郁夫, 小川 徳哉
原稿種別: 本文
p.
60-61
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
A thermoacoustic engine is a equipment which changes heat into acoustic sound. If this equipment is realized, it can be used as a power source of a thermoacoustic refrigerator. We made a resonance pipe engine and tried to verify its operation. A stack, which serves as a heat storage element, was inserted in a resonance pipe. Various attempts were made to produce stable acoustic sound, by changing total pipe length, stack position in the pipe, and temperature difference between the stack ends. Generation of unsteady acoustic sound was obtained when the beginning of cooling the high temperature stack. It is suggested by an experiment of that the suitable position of the stack is in between the displacement node and antinode of a sound wave.
抄録全体を表示
-
犬伏 政人, 戸倉 郁夫, 小川 徳哉
原稿種別: 本文
p.
62-63
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
A thermoacoustic refrigerator is a equipment that pumps up heat by acoustic sound. A resonance pipe refrigerator, which is one of thermoacoustic refrigerators, has many advantages, such as compact, simple structure, no moving parts, and so on. We made a resonance pipe refrigerator and verified its operation. A stack, which serves as a heat storage element, was inserted in the resonance pipe. Temperature difference of the stack ends, was measured by changing location of the stack in the pipe. It is indicated that the suitable position of the stack is in between pressure node and antinode of sound wave. Possibility of multi-stack operation is also discussed.
抄録全体を表示
-
石山 達也, 矢野 猛, 藤川 重雄
原稿種別: 本文
p.
64-65
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
-
岩瀬 義直, 池川 昌弘, 山田 雅彦, 川南 剛, 林 知生
原稿種別: 本文
p.
66-67
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The purpose of this study is to investigate the behavior of a single bubble adhering to the wall in the steady uniform flow. We stuck a bubble on the wall in a channel filled with water, and measured the departure fluid velocity which means the velocity that the bubble is separated from the wall. At the same time, we took photographs of the behavior of the bubble by a high-speed camera. From the experimental results, the projected area of the bubble into flow direction is found to be dominant as a factor of the bubble shape to determine the departure fluid velocity. Furthermore, we derived a formula for the bubble departure fluid velocity from the equilibrium condition between the work done by the bubble departure and the work by the fluid drag, and confirmed that it agrees well with the experimental results.
抄録全体を表示
-
加藤 功太, 山田 雅彦, 池川 昌弘, 川南 剛, 千葉 紘太郎
原稿種別: 本文
p.
68-69
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
This study focuses on the effect of contact surface pressure on the effective thermal conductivity of a powder layer. Experiments were performed to measure the effective thermal conductivities of both Al and Ni powder under various loading conditions. The measured results almost coincide with those by Kunii's model in case of without loading. However, under loading conditions, experimental results become much larger than those by Kunii's model, and the differences between these two become large as the load increases. This tendency is considered as due to the effect of contact surface pressure on the thermal resistance between particles.
抄録全体を表示
-
毛利 正樹, 花岡 裕, 久保田 智, 井坂 秀治
原稿種別: 本文
p.
70-71
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
In the case of flashing process of cryogenic fluids such as a liquid nitrogen, the mist formation has been observed in the vapor phase near the vapor-liquid surface at the early stage of the depressurization process. In the experiment, the relation between the mist formation and level of liquid nitrogen was examined. The present investigation focused on mist formation when liquid nitrogen does not exist. The experimental results show that the mist formation had not been observed.
抄録全体を表示
-
須藤 誠, 藤田 修, 伊藤 献一
原稿種別: 本文
p.
72-73
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Combustion of heavy fuel droplet in microgravity was studied. The tested fuels were n-nonadecane and LCO. The external air flow velocity in the combustion chamber was 4.7cm/s. Laser extinction method has been used to measure droplet diameter and to visualize the soot distribution in the flame. Results showed that burning rate and soot volume increased with O_2concentration in the test of n-nonadecane. LCO combustion produced more soot than n-nonadecane and had lower burning rate than n-nonadecane in the same condition.
抄録全体を表示
-
清水 圭祐, 藤田 修, 伊藤 献一, 高橋 絢也
原稿種別: 本文
p.
74-75
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Gasification of coal with CO_2 under high temperature and elevated pressure has been investigated in normal and microgravity. The results showed that the increase in CO_2 pressure increased the gasification reaction rate. Further, the reaction rate was affected by the gravitational condition, that is, higher reaction rate in microgravity than in normal gravity. It seemed that natural convection is so strong that coal gasification was suppressed under normal gravity. On the other hand gasification reaction proceeded under microgravity because enough reaction time was available with reduced external flow.
抄録全体を表示
-
田 炳浩, 藤田 修, 伊藤 献一
原稿種別: 本文
p.
76-77
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Combustion could be sustained even in ultra low oxygen concentration by utilizing highly preheated air. In this research, methane combustion in high temperature air is examined to know the fundamental characteristics of high temperature combustion. Intensity of heat release distribution is estimated by analyzing spatial distribution of carbon monoxide, which is a main intermediate of methane combustion. The results showed that the broad distribution of heat release could be attained with high temperature and low oxygen content. Using this combustion method to the industrial furnace, it is anticipated that the homogeneous heating or heat controlling of the furnace.
抄録全体を表示
-
藤澤 一樹, 藤田 修, 伊藤 献一
原稿種別: 本文
p.
78-79
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Flame synthesis of carbon nanotubes has been attempted in microgravity diffusion flame. The experiments were carried out with different fuel in various oxgen concentrations. Carbon nanotubes were collected from the diffusion flame for subsequent transmission electron microscopy (TEM) analysis by TEM grid. Finally some multi-walled carbon nanotubes with a diameter in the range of 5-20nm were found to grow on a Fe particle in diffusion flames. It was suggested that Fe particles acted as catalyst and flame synthesis could be a large-scale production method of carbon nanotubes.
抄録全体を表示
-
河辺 隆夫, 小川 英之, 宮本 登
原稿種別: 本文
p.
80-81
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The formation characteristics of combustion intermediate products were investigated by chemical kinetics with aid of CHEMKIN code. The intermediate products include CH_4,C_2H_4,HCHO, C_3H_6,C_4H_6 and others. The temperatureequivalence ratio areas where the intermediates were formed much and easier were specified for each intermediate, showing the specified area of higher equivalence ratio and the temperature ranging approximately from 800K to 1100K for almost of the intermediates. Dominated chemical reactions were investigated for each intermediate. Besides, formation characteristics of NOx, particularly N_2O, were also investigated.
抄録全体を表示
-
脇田 督司, 沼倉 龍介, 永田 晴紀, 戸谷 剛, 工藤 勲
原稿種別: 本文
p.
82-83
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Quick initiation of a detonation wave in a combustion chamber is important to realize a high-performance pulse detonation engine. A possible method is to generate a detonation wave in a shock-tube and release the detonation wave into the chamber. In this paper, a reflecting board is installed in the combustion chamber near the shock-tube exit where the pipe diameter expands sharply. It prevents the detonation wave disappearing at the expanding area near the shock tube exit. The relation of the cell size at the shock-tube exit and the distance between the shock-tube exit and the reflecting board is investigated in various initial pressures and rates of dilution of argon. Main results obtained in this study are in the following : The cell size in the shock tube can define the propagation limit of the detonation wave in the combustion chamber regardless of initial pressure and the rate of dilution of argon. The optimal distance of reflecting board was found to be 15 mm from the shock-tube exit.
抄録全体を表示
-
渡辺 賢, 橋本 望, 永田 晴紀, 戸谷 剛, 工藤 勲
原稿種別: 本文
p.
84-85
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Because of some defects, such as low combustion efficiency and O/F shift, Hybrid Rocket Motors have not been practicable yet. To overcome these defects of conventional Hybrid Rocket Motors, End-Burning Hybrid Rocket Motor has been suggested. In this rocket motor, oxidizer gas is injected from one side of a porous solid fuel grain and combustion occurs on the other side. If the oxidizer flow velocity in the gaps of the porous solid fuel is sufficiently high, the flame cannot spread into these gaps. This type of combustion is called Stabilized Combustion. Understanding of fuel regression characteristics is important to develop the End-Burning Hybrid Rocket Motor. In this paper, the fuel regression characteristics of porous solid fuels are investigated experimentally, and feasible arrangement of the gaps in the porous solid fuel for End Burning Hybrid Rocket Motor is shown.
抄録全体を表示
-
藤井 篤之, 栗田 慎一郎, 永田 晴紀, 戸谷 剛, 工藤 勲
原稿種別: 本文
p.
86-87
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The authors have been proposed staged combustion hybrid rocket to overcome defects of conventional hybrid rockets such as low combustion efficiency, Isp loss due to O/F shift, and poor throttling characteristics. This hybrid rocket mainly consists of primary and secondary combustion chambers. The primary combustion chamber, which generates fuel-rich combustion gas, functions as a fuel tank and contains unsaturated polyester resin pellets as solid fuels. Experimental results show that O/F in the primary combustion chamber is independent of oxygen flow rate if the residence time is long enough. The regression rate of the fuel pellet is expected to decrease with increasing the pellet diameter.
抄録全体を表示
-
安藤 博和, 金子 真也, 小川 英之, 宮本 登
原稿種別: 本文
p.
88-89
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The control of ignition and combustion behavior in a premixed charge compression ignission engine was investigated and ultra-low NOx and smokeless combustion was achived with direct in-cylinder injection of methanol as a reaction suppressor. The combustion suppression effect increases with advanced timing of methanol injection as the methanol becomes more widely distributed. With increases in methanol injection quantity, the appearance of low temperature oxidation is delayed and the heat release during low temperature oxidation decreases. With optimized methanol injection timing and injection quantity, the premixed charge compression ignition operational range could be expanded to 0.9 MPa IMEP, which is comparable to ordinary diesel operation.
抄録全体を表示
-
引地 清徳, 金子 真也, 小川 英之, 宮本 登
原稿種別: 本文
p.
90-91
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
The reaction suppression effect of direct methanol injection on PCCI combustion was analyzed with a bottom-view type engine and a high-speed video camera with an image intensifier. The result shows that with methanol injection the appearance of luminous flame is delayed and flame luminosity decreases during both low and high temperature oxidation. Earlier methanol injection results in more effective reaction suppression and lower flame luminosity. The visualized results correspond well with the analysis of the rate of heat release.
抄録全体を表示
-
加我 仁信, 登坂 茂, 藤原 康博
原稿種別: 本文
p.
92-93
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
There is a method of improving fuel as one of the reduction methods of the particle discharged from a diesel engine. Therefore, it is required to clarify the quality of fuel and the relation of the formation mechanism of a particle and the generation characteristic. In this research, fluid reaction tube was used, fuel concentration and heating time were set constant about the various fuel with which quality differs, a part for the heat decomposition at the time of changing temperature and heating it and polycyclic aromatic hydrocarbons, and analysis and measurement of particulate were performed, and the relation of quality, a formation mechanism, and the generation characteristic was investigated. The result is reported.
抄録全体を表示
-
安斉 英憲, 近久 武美, 菱沼 孝夫
原稿種別: 本文
p.
94-95
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
Rapid mixing of fuel and air is an essential factor in improving combustion and emissions of diesel engines. The objective of this study is to analyze the microscopic diffusion phenomena in diesel sprays. The result of the experiment shows that swirl flow affects on macroscopic distribution of sprays, but it does not alter the microscopic diffusion structure significantly. As the diffusion field becomes larger by the swirl flow with the same turbulence energy, swirl appears to reduce local diffusion intensity.
抄録全体を表示
-
塚原 栄二, 平岡 亜弥子, 佐々木 正史, 遠藤 登
原稿種別: 本文
p.
96-97
発行日: 2002/10/05
公開日: 2017/06/19
会議録・要旨集
フリー
On Aug 10,31 in 2001,we surveyed about 50km to 100km of coast in the Sea of the Okhotsk in order to measure. The survey of dissolved methane concentrations was carried out along the Kitami Yamato Tai off Abshiri shore in summer. Anomalous methane concentrations were found again at the station#2,named KIT-2,which was often located in a 'cool spot'. In 2002 sea ice season (from the end of 2001 to 2002), dissolved methane concentrations anomalies were detected again drifted from offshore of Saharine as in the same last season. Undetectable methane was observed before grounding of drift ice in previous season On the contrary, anomalous methane concentrations were found before the drift ice groundings.
抄録全体を表示