静 工 工学部研究報告 - shizuoka university静 岡 大 学 工 学 部 研 究 報 告 第...
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静岡大学工学部研究報告 第
54
号
ISSN 0583-0915
静 岡 大 学
工 学 部 研 究 報 告
第 54 号
Report of the Faculty of Engineering
Shizuoka University
Hamamatsu, Japan
No.54
静 岡 大 学 工 学 部
2 0 0 3
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ま え が き
本報告は静岡大学工学部に所属する教官等の平成15年における以下の研究成果等を収録する。
学会誌に掲載または掲載が決定された論文2編以上を、または掲載論文と講演発表をまとめた研
究論文
未発表の研究論文
年内に発表された研究論文の抄録
博士論文要旨
年内に特許証の交付された国有特許の明細書抄録
年内に発表された研究成果の一覧
修士論文題目(平成15年度修了生)
The Report of the Faculty of Engineering, Shizuoka University, is published annually by
the Faculty of Engineering, Shizuoka University, Hamamatsu Japan.
Papers in the Report are authored or coauthored by the members of the Faculty of
Engineering, Shizuoka University.
The Present issue includes:
Papers made up of (i) two or more papers published previously in accepted by other
scientific and engineering journals or of (ii) a published paper and additional materials
presented at conferences and meetings.
Original research papers.
Abstracts of papers published in other scientific and engineering journals in 2003.
Summaries of doctoral theses.
Gazettes of specifications of government-owned patents granted in 2003.
The list of research works disclosed in 2003.
The list of theses for the Master's Degree of Engineering, Graduate School, Shizuoka
University, March 2004.
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目 次
ま え が き
論 文 抄 録
機 械 工 学 科 …………………………………………………………………………………… 1
電気・電子工学科 …………………………………………………………………………………… 18
物 質 工 学 科 …………………………………………………………………………………… 31
システム工学科 …………………………………………………………………………………… 51
共 通 講 座 …………………………………………………………………………………… 73
研 究 成 果 一 覧
機 械 工 学 科 …………………………………………………………………………………… 76
電気・電子工学科 …………………………………………………………………………………… 94
物 質 工 学 科 …………………………………………………………………………………… 119
システム工学科 …………………………………………………………………………………… 151
共 通 講 座 …………………………………………………………………………………… 169
修 士 論 文 題 目 …………………………………………………………………………………… 172
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Contents
Foreword
Abstracts of Published Papers
Department of Mechanical Engineering …………………………………………………… 1
Department of Electrical and Electronics Engineering ………………………………… 18
Department of Materials Science and Chemical ………………………………………… 31
Department of Systems Engineering ………………………………………………………… 51
Mathematics, Physics, Chemistry …………………………………………………………… 73
List of Member's Research Works
Department of Mechanical Engineering …………………………………………………… 76
Department of Electrical and Electronics Engineering ………………………………… 94
Department of Materials Science and Chemical ………………………………………… 119
Department of Systems Engineering ………………………………………………………… 151
Mathematics, Physics, Chemistry …………………………………………………………… 169
List of Theses for Master's Degree of Engineering …………………………………………… 172
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1論 文 抄 録
学位論文要旨
Abstract of Doctoral Thesis
Masayuki Ishihara
Title of Thesis:Study on the Strength and
Deformation of Piezoelectric Smart Composites
Subjected to Mechanical, Thermal and Electrical
Loads
Abstract:
Recently, piezoelectric smart composites such
as piezothermoelastic laminates and piezoelec-
tric fiber composites (PFCs) have attracted
much attention in such applications as aero-
space engineering, micro electro-mechanical
systems and so forth. In designing these smart
composites, one should pay attention to their
strength because heterogeneity induces stress
concentrations and intrinsic brittleness of pi-
ezoelectric ceramics leads the composites to
fracture. Moreover, in these application, control
of deformation due to environmental changes is
an important issue for the composites to adapt to
the changes and to keep satisfying the required
accuracy. In the thesis, therefore, the strength
of PFCs and the deformation of piezother-
moelastic laminates are studied.
In Chapter 2, the governing equations for pi-
ezoelectric materials are presented.
In Part II, the strength of PFCs considering
interaction among fibers is studied. In Chapter3,
the effect of interaction among piezoelectric fi-
bers in PFCs on the electroelastic field and the
susceptibility to fracture is investigated with the
analytical model where a piezoelectric infinite
body with piezoelectric uncracked or cracked
inhomogeneities is subjected to remote me-
chanical and electrical loads. It is found that
distributions of stress and electric displacement
in the uncracked body become more non-uni-
form for smaller distance between two inhomo-
geneities or for larger dimension of the adjacent
ihhomogeneity and are homogeneized by ap-
propriate application of remote electric dis-
placement; that stress intensity factor (SIF) due
to remote stress gets larger for larger distance
between two inhomogeneities, for location of
the crack more remote from the adjacent inho-
mogeneity or for larger crack length and is
changed by application of remote electric dis-
placement. Then, in Chapter 4, the susceptibility
to interface debonding in PFCs is investigated
with the analytical model where a piezoelectric
infinite body with two interface cracks between
matrix and an inhomogeneity is subjected to re-
mote mechanical and electrical loads. It is
found that SIF and electric displacement inten-
sity factor (EDIF) get maximum when only one
crack with 2π/3 opening exists between the
matrix and the inhomogeneity and that, when
the lengths of two cracks are same, SIF and EDIF
get maximum when each crack has π/2 open-
ing.
In the following Part III composed of Chapters
5 through 9, deformation considering damping
due to interlaminar shear and non-linear dy-
namic deformation considering transverse shear
are studied. In Chapter 5, the governing equa-
tions for piezothermoelastic laminates subjected
to mechanical, thermal and electrical loads are
derived considering the effects of transverse
shear and damping due to interlaminar shear.
The equations of motion with damping terms
proportional to rotary velocities are obtained by
introducing the interlaminar shear stresses sat-
isfying the Newton's law of viscosity based on
the FSDT. In Chapter 6, the effect of transverse
shear on the static deformation-control of a pi-
ezothermoelastic symmetrical cross-ply rectan-
gular laminate subjected to mechanical, thermal
and electrical loads is investigated. It is found
that the effect of transverse shear on the de-
flection gets more significant as the
length-to-thickness (LT) ratio decreases. In
Chapter 7, the study on the dynamic
deformation-control of a piezothermoelastic
rectangular laminate subjected to mechanical,
thermal and electrical loads is performed. It is
found that the transient deflection due to a uni-
form and constant transverse load can be sup-
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2 論 文 抄 録
pressed by applying sustaining uniform electri-
cal voltage to the piezoelectric actuator; that the
transient deflection due to a partially distributed
and impulsive transverse load can be sup-
pressed by appropriate pulse of uniform electri-
cal voltage to the piezoelectric actuator; that the
magnitude of voltage and the initial time and
duration of electrical pulse to minimize the
suppression rate of the deflection in the lami-
nate due to a partially distributed and impulsive
transverse load are obtained. In Chapter 8, the
effect of damping due to interlaminar shear on
the dynamic deformation-control of a piezo-
thermoelastic symmetrical cross-ply rectangular
laminate subjected to mechanical, thermal and
electrical loads is investigated. It is found that
the minimum damped natural frequency de-
creases and the decay rate increases by the
damping due to interlaminar shear; that the final
deflection due to a sudden and sustaining
transverse load or temperature change can be
suppressed by applying sustaining electrical
voltage to the piezoelectric layer; that the con-
trol electrical voltage for the mechanical de-
flection increases and that for the thermal de-
flection decreases as the LT ratio increases; that
the transient deflection due to a partially dis-
tributed and impulsive transverse load can be
suppressed by appropriate pulse of uniform
electrical voltage to the piezoelectric actuator;
that the magnitude of voltage and the initial time
and duration of electrical pulse to minimize the
suppression rate are obtained. In Chapter 9,
non-linear dynamic deformation-control of a
piezothermoelastic symmetrical cross-ply rect-
angular laminate subjected to mechanical, ther-
mal and electrical loads is studied considering
the effect of transverse shear. The non-linearity
of the deflection with respect to thermal and
electrical loads is shown qualitatively and it is
found that application of an appropriate electri-
cal voltage to the piezoelectric actuators can
rise the buckling temperature and the natural
frequency of infinitesimal oscillation and lin-
earize the large deflection with respect to tem-
perature and the natural frequencies with re-
spect to the finite amplitude.
In Part IV, concluding remarks are stated.
Fatigue Strength and Damage Behavior of
Glass Particle Reinforced Nylon 66 Composites
K. Tohgo, Y. Itoh and T. Kim
ガラス粒子強化ナイロン66複合材料の
疲労強度と損傷挙動
東郷敬一郎、伊藤靖朗、金 泰佑
In this paper, fatigue strength and damage
behavior of glass-particle reinforced nylon 66
composites have been investigated. Fatigue
tests were carried out on seven kinds of
glass-particle reinforced nylon 66 composites in
which a volume fraction of glass particles and
interface treatment between particles and ma-
trix were changed. Variation of stiffness with
fatigue was determined from the equilibrium
stress-strain relations obtained by multi-step
relaxation tests after given stress cycles to elim-
inate the influence of viscoplasticity of a nylon
66 matrix. The fatigue strength is low in the
interface-untreated composite and is high in the
interface-treated composite as compared with
that of the nylon 66. The stiffness reduces sig-
nificantly at the early stage of stress cycles and
then becomes constant in the nylon 66 and both
composites. The stiffness reduction is more re-
markable in both composites than in nylon 66
because of the debonding damage. From the
variation of the equilibrium stress-strain rela-
tions with fatigue, it is found that the viscoplastic
component of deformation gradually disappears
with increasing stress cycles.
[9th Int. Conf. Mechanical Behavior of Materials,
(2003. 5)]
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3論 文 抄 録
Fatigue Behavior of CFRP Cross-Ply Laminates
under Axial Cyclic Load
K. Tohgo, X.-J. He, H. Ishii and K. Kageyama
主軸方向繰返し荷重を受ける
CFRP直交積層板の疲労挙動
東郷敬一郎、賀 小軍、石井 仁、影山和郎
Laminated composites consisting of unidirec-
tional plies exhibit the complicated characteris-
tics on deformation and strength because
ply-cracking damage, delamination and fiber
breakage develop from an early stage of defor-
mation. In this paper, the damage and fracture
process of CFRP cross-ply laminates under
monotonic and cyclic loading has been investi-
gated. Tensile tests in various directions and
fatigue tests in the axial direction were carried
out on three kinds of CFRP cross-ply laminates.
In the tensile tests, the ply-cracking damage
develops under 0°and 90°tension, while the
nonlinear deformation due to nonelastic prop-
erty of the matrix resin is predominant under
off-axis tension. On the semi-log S-N curves
obtained by the fatigue tests in the 0°direction,
the fatigue fracture is described by a straight line
in the high cycle fatigue region and the fatigue
limit is not recognized clearly. In the fatigue
tests, the fiber-peeling damage in 0°plies de-
velops in addition to the ply-cracking damage in
90°plies. Ply-cracking density in 90°plies is
characterized as a function of number of stress
cycles. On the specimen fractured by fatigue,
the most of ply-cracking damage develops at the
first cycle, and slightly increases during fatigue.
This damage behavior is insensitive to the stress
level. Therefore, it is concluded that the
ply-cracking damage is not a main factor con-
trolling the fatigue fracture. On the other hand,
fiber-peeling damage in 0°plies initiates from
the edges of 0°plies and evolves in the whole
area of the laminate with an increase in stress
cycles. The evolution of the fiber-peeling dam-
age strongly depends on the stress level. The
fatigue fracture seems to occur when the 0°
plies lose their load carrying capacity by the
evolution of the fiber-peeling damage. There-
fore, it is concluded that the fiber-peeling dam-
age in 0°plies is the main factor controlling fa-
tigue fracture.
[Int. Conf. Advanced Technology in Experi-
mental Mechanics 2003, (2003. 9)]
Influence of Coarsening Treatment on Fatigue
Strength and Fracture Toughness of Al-Si-Mg
Alloy Casting
Keiichiro Tohgo1 and Masahide Oka
Al-Si-Mg合金鋳物の疲労強度と
破壊靱性に及ぼすコースニング処理の影響
東郷敬一郎、岡 政秀
In this paper, the influence of the coarsening
treatment of eutectic Si particles on fatigue
strength and fracture toughness of a peak-aged
Al-7%Si-0.4%Mg alloy casting has been investi-
gated. By the coarsening treatment at 808°K for
100 hours, the eutectic Si particles grew to be
spherical and were uniformly distributed, but
casting defects remained without any changes.
On tensile tests, the 0.2% proof stress and tensile
strength were almost the same in both as-re-
ceived material and Si-coarsened material, but
the ductility was much higher in the Si-coars-
ened material than in the as-received one. Fa-
tigue fracture occurred by crack initiation from
the casting defects and succeeding crack growth
on both materials, and the fatigue strength of the
materials was affected by the size of defects
rather than by the coarsening treatment. On the
other hand, the fracture toughness was distinctly
improved by the coarsening treatment. It is
suggested that the improvement of fracture
toughness in the Si-coarsened material is at-
tributed to the energy dissipation due to the
damage of Si particles around a crack and the
rough fracture path.
[5th Int. Conf. Fracture and Strength of Solids,
(2003. 10)]
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4 論 文 抄 録
形状記憶合金複合材料の特殊機能制御に
関する基礎的研究
村澤 剛、米山 聡、東郷敬一郎、隆 雅久
Basic Research for Controlling Unique
Performances of Shape Memory Alloy
Composite
G. Murasawa, S. Yoneyama,
K. Tohgo and M. Takashi
本研究では、まず、形状記憶合金複合材料 (SMAC)
における形状記憶合金繊維とマトリックスの組合せ、
繊維体積率による特殊機能発現に関して解析的検討を
行った。続いて、数種類のSMACの熱負荷による変形
特性をデジタルイメージ修正法を用いて測定し、さら
に、マトリックスの内部応力を光弾性法を用いて測定
した。本研究により以下の結果が得られた。SMAC
の熱負荷による変形特性とマトリックス内の圧縮応力
は繊維体積率およびマトリックス材料に依存し、得ら
れた特性マップはSMACの設計に有益である。ポリ
エステルに予ひずみを与えたNiTi繊維を含むSMAC
を加熱すると、大きな収縮変形とマトリックス内の圧
縮応力が生じる。実験により得られた変形特性と解析
結果には若干の差が見られた。したがって、より精度
の高い解析モデルの開発が必要である。
[実験力学、Vol. 3, No.3, pp. 172-178, (2003. 9)]
Control of Mechanical Deformation of a Laminate
by Electrical Load to Piezoelectric Actuator
Considering the Effects of Damping and
Transverse Shear
Masayuki ISHIHARA, Naotake NODA
Abstract:
In this paper, we treat the control of dynamic
deformation of a laminate by applying electrical
load to piezoelectric actuator. Dynamic behav-
ior of the laminate is analyzed considering the
effect of damping due to interlaminar shear and
the effect transverse shear. The analytical
model is a rectangular laminate composed of
fiber-reinforced laminae and piezoelectric lay-
ers. The model is assumed to be a symmetric
cross-ply laminate with all egdes simply sup-
ported and to be subjected to unavoidably me-
chanical load and to electrical loads to piezo-
electric actuator. Behavior of the laminate is
analyzed based on the first-order shear defor-
mation theory. The effect of damping due to
interlaminar shear is incorporated into our
analysis by introducing the interlaminar shear
stresses which satisfy the Newton's law of vis-
cosity. The following quantities are obtained:
natural frequencies of the laminate, weight
functions for the deflection and rotations and
transient deflection due to loads varying arbi-
trarily with time. Moreover, the methods to
control the deflection due to mechanical load by
applying electrical voltage to the piezoelectric
actuator are shown.
[International Journal of Engineering Science,
41 (15), pp. 1667-1684]
Effect of Damping on Dynamic Behavior of a
Piezothermoelastic Laminate
Considering the Effects of Transverse Shear
Masayuki ISHIHARA & Naotake NODA
Abstract:
In this paper, we analyze dynamic behavior of
a piezothermoelastic laminate considering the
effect of damping due to interlaminar shear and
the effect of transverse shear. The analytical
model is a rectangular laminate composed of
fiber-reinforced laminae and piezoelectric lay-
ers. The model is assumed to be a symmetric
cross-ply laminate with all egdes simply sup-
ported and to be subjected to mechanical, ther-
mal and electrical loads varying arbitrarily with
time. Behavior of the laminate is analyzed based
on the first-order shear deformation theory.
The effect of damping due to interlaminar shear
is incorporated into our analysis by introducing
the interlaminar shear stresses which satisfy the
Newton's law of viscosity. Solutions of the fol-
lowing quantities are obtained: natural fre-
quencies of the laminate, weight functions for
the deflection and rotations and unsteady
deflection due to loads varying arbitrarily with
time. Moreover, numerical examples of the so-
lutions are shown to examine the effects of
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5論 文 抄 録
damping and transverse shear on dynamic be-
havior of the laminate and how the voltage ap-
plied to the laminate decreases the deflection
due to mechanical or thermal loads.
[International Journal of Solids and Structures,
40 (22), pp. 6077-6094]
Non-linear Dynamic Behavior of a
Piezothermoelastic Laminate
Considering the Effect of Transverse Shear
Masayuki ISHIHARA, Naotake NODA
Abstract:
Non-linear dynamic behavior of a piezother-
moelastic laminate subjected to mechanical,
thermal and electrical loads is analyzed consid-
ering. Non-linear deformation of the laminate is
analyzed based on the von Kármán strains and
the first-order shear deformation theory using
the Galerkin Method. The buckling tempera-
ture, the large static deflection, the natural fre-
quencies of infinitesimal or finite oscilation are
discussed. The effect of transverse shear on
non-linear behavior and the methods to rise the
buckling temperature, to linearize thermal de-
flection and the natural frequencies by applying
the electrical voltage to piezoelectric actuators
are investigated.
[Journal of Thermal Stresses, 26 (11-12), pp.
1093-1112]
Development of torsional damper with crowd
of solid balls for engine crankshaft
Takashi MATSUDA and Motohiro SATO
エンジンのクランク軸用の
粒子トーショナルダンパの開発
松田 孝、佐藤元宥
In this paper, new torsioinal damper is devel-
oped in order to improve the defects of known
dampers such as rubber dampers, oil dampers
and solid frictional dampers, which are used for
vibration reduction of crankshafts in most of
reciprocating engines for automobiles. The
damper is designed and manufactured, and the
experiments on the vibration reduction carried
out. As a result, it is suggested that those defects
can be improved by this experimental damper,
and that the effective damping is achieved by
the new damping mechanism, that is, the fluc-
tuation of the natural frequency of testing
crankshaft system caused by alternating be-
tween the angular sliding and the coupling of
damper mass to the damper casing in every pe-
riod of the torsional vibration of the crankshaft.
[J. Mech. Eng., Vol.54, No.2, pp. 101-110 (2003)]
粒子トーショナルダンパの開発
(制振機構のシミュレーション)
佐藤元宥、松田 孝、今田琢己
Development of Torsional Damper
with Crowds of Solid Balls
(Simulation of Damping Mechanism)
Motohiro SATO, Takashi Matsuda
and Takumi IMADA
これまでに、新開発の粒子トーショナルダンパは粒
子の量の調整により、クランク軸系のねじり振動を効
果的に低減することが実験的に明らかにされてきてい
る。本研究では、ダンパの最適設計のための基礎とし
てこの減衰機構が明らかにされている。まず、本ダン
パを備えた供試クランク軸系のねじり振動のモデリン
グとコンピュータシミュレーションを行い、ついで、
それらの結果を実験結果と比較検討して、本ダンパの
制振機構は、粒子群とダンパマス間の摩擦損失および
ねじり振動の一周期中にダンパマスとダンパケース間
にカップリングとすべりが交互に生じることから構成
されていることを明らかにしている。
[日本機械学会論文集 (C編)、69巻 680号、pp.
1178-1183 (2003)]
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6 論 文 抄 録
Accuracy Improvement of Parallel Kinematic
Machine: Compensation Method for Elastic
and Thermal Deformation of Machine Frame
Takaaki OIWA
パラレルメカニズム型機械の精度向上に関する研究
・機械フレームの弾性および熱的変形の補正方法̶
大岩孝彰
To improve the machining and measuring ac-
curacy during the process, it is extremely im-
portant to obtain an accurate relative position
between the tool and the workpiece. Thus, not
only moving accuracy but also structural and
thermal stability in the whole machine is re-
quired. In general, to compensate such thermal
deformation, many researchers have investi-
gated prediction methods with limited tempera-
ture sensors and analyzed by using the finite el-
ement method. However, the thermal deforma-
tion is hard to predict and analyze because the
sensors can not measure the temperatures of all
parts of machine. Moreover, the analysis in the
machine comprised of beam structure involves
the great difficulties because of its complexity of
the deformation at rapid fluctuation of the room
temperature. This study deals with the accuracy
improvement for parallel kinematic machine
consisting of closed loop link mechanism. This
paper describes a compensation method for
both elastic and thermal deformations of the
machine flame supporting the mechanism.
These deformations are caused by the heat, the
external forces and the internal forces. Nine
displacement sensors with nine Super-Invar
rods measure the variation of distances between
the surface plate and three joint supports on the
frame. The direct kinematics of Hexapod
mechanism calculates the displacement and the
attitude variations of the frame during operation
from measured displacements. Consequently,
the coordinates of the end effector are com-
pensated by these displacements and attitude of
the mechanism. Experimental results show re-
duction of the influence of the temperature
fluctuation.
[The euspne International topical conference
on precision engineering, Micro-Technology,
Measurement Techniques and Equipment, Vol.1,
pp. 125-128 (2003)]
Accuracy Improvement of Parallel Kinematic
Machine-Error Compensation Methods for
Elastic and Thermal Deformations of Joints,
Links and Machine Frame-
Takaaki OIWA
パラレルメカニズム型機械の精度向上
ジョイント・リンクと機械フレームの弾性
および熱的変形の誤差補正方法̶
大岩孝彰
This paper describes compensation methods
for deformations of both the parallel kinematic
mechanism and the frame supporting the
mechanism. In general, these deformations are
caused by the heat, the internal forces and the
external forces during the processes. First,
runouts and deformations of spherical joints and
revolutionary joints are measured and compen-
sated by nine displacement sensors built in
above joints or by linear scale units built in the
prismatic joints. Second, the longitudinal de-
formation of the prismatic joints is mechanically
compensated by Super-Invar rod connected to
the joints and the linear scale units. Moreover,
nine displacement sensors with nine Super-In-
var rods measure the variation of distances be-
tween the surface plate and three spherical joint
supports. Consequently, the forward kinematics
of Hexapod mechanism calculates the displace-
ment and the attitude variations of the mecha-
nism during operating from measured data.
Last, the coordinates of the end effector are
compensated by these displacements and at-
titude of the mechanism. Experimental results
show reduction of the influence of the tempera-
ture fluctuation and variation of measured val-
ues.
[Tokyo Institute of Technology The 6th Interna-
tional Workshop of the Department of Me-
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7論 文 抄 録
chanical Sciences and Engineering, (2003)]
6自由度パラレルメカニズムにおける
アッベの原理に関する研究
(対偶の回転誤差が機構の運動誤差に及ぼす影響)
大岩孝彰、玉木雅人
直動型の能動対偶6本を持つ表記機構の球対偶の回
転誤差が機構の運動誤差に及ぼす影響とリンク配置の
関係を調査した。微小運動学を用いた誤差解析の結果、
直進対偶方向の回転誤差のみが運動誤差に強く影響す
ること、この影響が最小となるリンク配置があること、
このとき位置決め分解能や作業領域は最小化し、出力
点は直進対偶の延長線と最も近づくが、延長線上を通
る必要はないことなどがわかった。またこのような配
置の時、パラレルメカニズムはアッベの原理を満たす
ことがわかった。
[日本機械学会論文集C編, 69巻678号, pp. 472-477
(2003)]
パラレルメカニズムを用いた三次元座標測定機の
校正に関する研究・ダブルボールバーと
タッチプローブを用いたキャリブレーション̶
大岩孝彰、片岡頼洋
リンクを並列に配置した閉ループ機構から成る表記
測定機において、あらかじめ校正されたダブルボール
バーの移動球をタッチプローブで測定して得られる位
置誤差から、対偶位置などの機構パラメータを最小自
乗法により推定した。移動球の配置、繰返し計算の打
ち切り回数の検討、および校正後の測定精度について
述べた。
[精密工学会誌, 69巻2号, pp. 222-226 (2003)]
外径絞りを伴う二段充てん法による平歯車の成形
沢木洋三、吉田 始、坂井田喜久、鈴木 正
著者らは前報で二段階の冷間押出しで内歯車やイン
ナーヘリカルスプラインを成形する方法を提案した。
この方法を外歯である平歯車の成形に適用した。すな
わち、円筒試料の外径を二段階で絞り平歯車を成形す
るための特別な形状のダイスを用いた。対象とした平
歯車の諸元はモジュール1.25、歯数18である。33%とい
う低い断面減少率の場合であっても、低いパンチ面圧
で実験したほとんど全てで良好な平歯車が得られた。
この方法の有利な点を調べるために FEM 解析を行っ
た。1) 一段目の押出しでは大きな歯形のために歯先
(半径方向) に向かう素材の流動が容易である。2) 一
段目の大きな歯形から目標とした歯形に成形する二段
目の押出しで、円周方向の素材の流動も生ずる。
[塑性と加工,44巻507号,pp. 462-466,(2003)]
Evaluation of Fracture Toughness of Porous
Ceramics
Yoshihisa Sakaida and Keisuke Tanaka
多孔質セラミックスの破壊靭性評価
坂井田喜久、田中啓介
The indentation fracture (IF) method, the
single-edge precracked beam (SEPB) method,
and the single-edge V-notched beam (SEVNB)
method were applied to evaluate the fracture
toughness of four kinds of porous ceramics of
SiC, Al2O3 and Mg2Al4Si5O18 with porosity rang-
ing from 37 to 43%. The microstructures of these
materials were composed of ceramics grains,
glassy grain boundaries and pores. Each grain
was joined together with the glassy grain
boundary phase. The IF and SEPB methods
were not applicable because both precracks and
indenter traces were not visible. On the other
hand, the SEVNB method was applicable be-
cause the V-notch could be easily machined by
grinding. In the case of the SEVNB method, the
applied load versus back-face strain plots under
four-point bending showed nonlinearity prior to
the maximum load. The R-curve behavior was
estimated from the compliance change of spec-
imens. The fracture toughness of porous ce-
ramics was smaller than that of dense ceramics,
and increased with increasing crack extension.
Since the stable crack predominantly propa-
gated along glassy grain boundaries, the
R-curve behavior depended on the loading rate
and matrix grain size. The increment of the
-
8 論 文 抄 録
R-curve by grain bridging became larger for
coarser-grain sized ceramics.
[JSME International Jornal, Series A, Vol.46,
No.1, pp. 30-39 (2003)]
Prediction of Homogenized Elastic Moduli of
Ceramics
Using Polycrystalline Grain Model
(Influence of Two-Dimensional
Microstructual Model Size)
Yoshihisa Sakaida and Koji Sato
多結晶粒子モデルによるセラミックスの
等価弾性係数評価
(二次元微構造モデル寸法の影響)
坂井田喜久、佐藤功二
Microstructures of polycrystalline Al2O3, ZrO2
and Al2O3-ZrO2 ceramics were modeled as
two-dimensional heterogeneous bodies com-
posed of geometeric Al2O3 and ZrO2 grains. The
crystallographic 3D-directions of each grain
were assumed to be randomly distributed.
Elastic properties of grain were derived from
elastic stiffnesses, cij, of single crystal Al2O3 and
ZrO2. In calculation, some square plates with a
unit thickness were cut from the initial grain
models. A simulation method was developed to
predict homogenized elastic moduli of models
using a finite element method. An influence of
the microstructual model size on apparent elas-
tic moduli was examined. Next, actual micro-
structual models that were traced the SEM mi-
crographs of samples were used in same calcu-
lation. And then, the optimum model size was
determined by comparing calculated elastic
moduli to experimental data measured by a
pulse-echo method. As a result, the scattering
of apparent elastic moduli, such as Young's
modulus, of both models including Al2O3 grains
varies narrowly with increasing model size.
While, the deviation of apparent elastic moduli
for actual model is wider than that of geometric
model on the same model size. The number of
Al2O3 grains within the optimum model size was
found to be about more than 400, in which the
scattering of apparent elastic moduli is below
the ±1% deviation of the mean value of model
samples.
[日本機械学会論文集 (A編), 69巻, 684号, pp.
1311-1317 (2003)]
In-situ Local Stress Measurement near Notch
Tip in Alumina Ceramics
Using Synchrotron Radiation Source
Yoshihisa Sakaida, Keisuke Tanaka, Yoshiaki
Akiniwa and Yozo Sawaki
シンクロトロン放射光による
アルミナの切欠き先端近傍の局所応力
坂井田喜久、田中啓介、秋庭義明、沢木洋三
In order to measure loading and residual
stresses near the notch tip in Al2O3 ceramics
using a micro X-ray beam of SPring 8 (Super
Photon ring-8GeV), X-ray elastic constants were
first determined experimentally. Mechanical
elastic constants of the used material were E=372
GPa and n=0.23. The diffraction from Al2O3 2.0.14
plane by 8keV radiation was used for X-ray
stress measurement. The 2q-sin2y diagrams un-
der several applied stresses were measured.
From the relationship between both slope, M,
and intercept 2qy=0 of 2q-sin2y diagram and ap-
plied stress, X-ray elastic constants were deter-
mined to be Ex=416 GPa and nX=0.20. Next, the
local stress measurement in the irradiated area
with 100×100 mm2 was examined in comparison
to that with 100×500 mm2. Loading stress in a
local area with 100×100 mm2 can be measured by
the sin2y method. Finally, the local loading
stresses, sy (x), near the V-notch tip under a
four-point bending load were measured across
the minimum ligament of SEVNB
(Single-Edge-V-notched Beam) specimen by
scanning the micro X-ray beam along the x-axis.
The stress concentration near the notch root
was first difficult to be measured directly be-
cause of the grinding residual stress by V-notch
machining. After annealing, the stress concen-
-
9論 文 抄 録
tration was detected by changing the irradiated
area of X-ray from 100×100 to 50×50 mm2. The
degradation of the measured stresses in the
notch tip was caused by the X-ray irradiation to
the notch, and almost agreed with the results of
a finite element analysis. The local stress and
residual stresses were found to be measured by
the sin2y method using synchrotron micro X-ray
beam with a spatial resolution of about 50 mm.
[材料, 第52巻, 第10号, pp. 1225-1230 (2003)]
Micro and Macro Stress Analysis of Ceramics
Using Microstructural Models
Yoshihisa Sakaida, Yasushi Ikeda, Hiroshi
Kawamoto and Yozo Sawaki
微構造モデルによるセラミックスの
ミクロ・マクロ応力解析
坂井田喜久、池田 泰、河本 洋、沢木洋三
Modeling techniques using either finite ele-
ment or homogenization methods were devel-
oped for predicting micro/macro stress fields in
ceramic components. In case of polycrystalline
film ceramics, the microstructure was modeled
as two dimensional grain models using the SEM
micrographs. Homogenized elastic moduli and
micro/macro stress fields were calculated by fi-
nite element analysis. Influence of the model
size on homogenized elastic moduli and mac-
rostress field was examined. Homogenized
elastic moduli and macrostress field for thin film
formed in limit number grains, such as MEMS
device, were found to be directly controlled by
both elastic anisotropy and crystallographic
orientation of grain within the microstructure.
Elastic anisotropy and crystallographic orienta-
tion of grain must be considered even if the
crystal structure of the material was cubic which
had relatively simple stiffness matrix. In case of
porous ceramics, the microstructure was mod-
eled as three dimensional porous models using
the computerized tomograms by X-ray. Ho-
mogenized elastic moduli were calculated by
homogenization analysis, and then macrostress
fields in joint bars composed of two different
porous materials were found to be estimated
from finite element analysis under four-point
bending.
[構造物の安全性および信頼性, Vol.5, pp. 159-166
(2003)]
Estimation of Elastic Modulus of
Polycrystalline Ceramics
using Microstructural Grain Model
Yoshihisa Sakaida, Yozo Sawaki and
Syusui Ogawa
微構造粒子モデルによる多結晶セラミックスの
弾性係数評価
坂井田喜久、沢木洋三、小川秋水
The simulation method was developed to pre-
dict homogenized elastic moduli of ceramic
materials from elastic stiffness of each grain
within its microstructure. Polycrystalline Al2O3,
ZrO2 and Al2O3- ZrO2 ceramics were produced
as model samples. Elastic stiffness, cij, of single
crystal cubic- ZrO2 was measured by four-point
bending method. Microstructures of model
samples were modeled as two and three-di-
mensional heterogeneous bodies composed of
Al2O3 and ZrO2 grains. The crystallographic
3D-directions of each grain were assumed to be
randomly distributed. Some square plates with a
unit thickness that cut from the initial two-di-
mensional grain models and some cubes com-
posed of geometeric cube grains were used to
calculate apparent macroscopic elasitc moduli
such as Young’s modulus, Poisson’s ratio and
modulus of rigidity. An influence of the model
size on apparent elastic moduli was examined
by a finite element method. And then, the opti-
mum model size was determined by comparing
calculated elastic moduli to experimental data
measured by a pulse-echo method. As a result,
the scattering of apparent Young’s modulus
varies narrowly with increasing the number of
anisotropic Al2O3 and ZrO2 grains. The number
of anisotropic grains within the optimum model
-
10 論 文 抄 録
was found to be about 400. The calculated elas-
tic moduli for the optimum model coincided
with the experimental data.
[Proceeding of International Conference on
Advanced Technology in Experimental Me-
chanics 2003, OS08W0215, pp. 1-6 (2003)]
Strength Evaluation of Aluminum Alloy Bold
by Nano-Indentation Hardness Test
Yoshihiro Kubota, Tamotsu Nakamura,
Mitsuo Kobayashi, Katsumi Fukuda
ナノ硬さ試験によるアルミニウムボルトの強度評価
久保田義弘、中村 保、小林光男、福田克己
Aluminum alloy bolts are used to joint two or
more aluminum space frames. Such aluminum
alloy bolts are required high strength. A high
strength aluminum alloy bolt (7050, T7 temper)
has been developed by the authors. The bolt
has a small grain size in all area of the bolt by
thermo-mechanical treatment. Moreover, the
ductility and stress corrosion cracking resis-
tance have been improved by over aging treat-
ment by T73 temper treatment. Recently, a
nano-indentation hardness has been developed
to evaluate the hardness in microscopic area. In
the present paper, the distribution of
nano9indentation hardness of microscopic grain
structure in the high strength aluminum alloy
bolt has been measured by nano-indentation
hardness tester.
[Acta Physica Universitatis Comenianae
Vol.XLIII, pp. 45-52 (2002)]
環境に優しい鍛造のトライボロジー技術
中村 保
Ecological Tribology in Forging
Tamotsu Nakamura
鍛造のトライボロジー技術は、摩擦管制、製品表面
仕上げ向上、焼付きや工具摩耗防止等の要求から必要
不可欠である。しかし、最近はとくに環境負荷の大き
な潤滑剤の使用は極力避けることが要求されている。
究極的には、潤滑剤なしで塑性加工を実現することが
理想的であるが、現状では、そこに至るまでの過程に
おいて、環境負荷を軽減するための種々のトライボロ
ジー技術が提案され、すでに実用化が進んでいる。本
論文では、環境負荷を軽減するために開発されてきた
種々の鍛造のトライボロジー技術について、調査した
結果をまとめる。
[月刊トライボロジー, 186号, pp. 33-37 (2003)]
Tribo-Testing Method for Estimating
Tribo-Characteristics at Piercing Punch in
Backward Can Extrusion
Tamotsu Nakamura, Shigekazu Tanaka,
Kunio Hayakawa, Isao Takahashi
缶の後方せん孔押出しのパンチ頭部の
トライボロジー特性評価方法
中村 保、田中繁一、早川邦夫、高橋 功
The authors have proposed a new type of
tribo-testing method based on a combined for-
ward straight can-backward straight can extru-
sion in order to evaluate tribo- characteristics at
the piecing straight punch with a long bearing
length. By this method the friction shear factor
mUP at the upper punch bearing can be deter-
mined after knowing the friction shear factor mD
along the die wall. The die wall friction shear
factor mD is determined by a tribo-testing
method based on a combined forward-back-
ward can extrusion. Calibration curves repre-
senting the relationship between punch travel,
can heights and friction shear factor for the two
-
11論 文 抄 録
tests have been calculated based on a
rigid-plastic FEM analysis. Experimental fric-
tion tests have been carried out with some min-
eral oils using a mechanical press.
[Lubrication Engineering, Vol.59, No.4, pp. 12-17
(2003)]
大学におけるトライボロジー教育 (塑性加工部門)
中村 保
University Education for Tribology in Metal
Deformation Processes
Tamotsu Nakamura
全国的に工学部の機械系学科のほとんどで、専門の
講義は基礎的な科目をみっちりと教えることに重点が
置かれ、専門の個別の分野の講義の種類はかなり削減
されているものと推測される。生産加工関連の講義も
例外ではなく、ここ数年で塑性加工単独の講義を実施
している大学はほとんどなくなっているのが現状では
なかろうか。日本技術者教育認定機構 (JABEE) の機
械および機械関連分野の分野別要件の「材料と構造」の
項目中に、「トライボロジー」のキーワードがあるため、
機械の一般的な摺動に関するトライボロジーについて
は、今後も、大学の講義でしっかりと学ぶ機会が残る
と考えられる。
JABEEにおける大学卒業後の技術者の生涯教育に
ついては、通産省の委託を受けて、例えば、機械分野
については、日本機械学会の「機械技術者生涯教育調査
委員会」が、教育プログラムや講習会の教材作成に責任
を持って当たることになりそうである。したがって、
たとえば、塑性加工のトライボロジーについては、日
本塑性加工学会が責任を持つことになる可能性が高い。
本稿では、塑性加工のトライボロジーに関する教育を
実施する際に、学会が果たすべき役割について考察す
ることにしたい。
[トライボロジスト, 48巻, 8号, pp. 615-621 (2003)]
直接通電加熱圧接による各種金属の接合条件
中村 保、田中繁一、早川邦夫、今泉晴樹、中川雄太
Pressure Welding Characteristics of Various
Metals by DC Pulse Resistance Sintering
Apparatus
Tamotsu Nakamura, Shigekazu Tanaka,
Kunio Hayakawa Haruki Imaizumi
& Yuhta Nakagawa
The authors haveproposed a new type of fric-
tion test based on combined forward straight
can-backward straight can extrusion in order to
evaluate friction characteristics at the long
bearing of the piecing straight punch. By this
method the friction coefficient at the punch
bearing is determined after knowing the friction
coefficient along the die wall. The die wall fric-
tion coefficient is determined by a combined
forward and backward can extrusion of straight
cans. Calibration curves determining the rela-
tionship between punch travel, can heights and
friction coefficient for the two tests are calcu-
lated based on a rigid-plastic FEM analysis.
Experimental friction tests are carried out in a
mechanical press with aluminum alloy A6061 as
the work-piece material and different kinds of
lubricants. They confirm that the theoretical
analysis results in reasonable values for the
friction coefficient.
[塑性と加工, 44巻, 512号, pp. 931-936 (2003)]
Recent Trends on Researches and
Technologies in Forging Processes in Japan
Tamotsu Nakamura
最近の日本における鍛造技術研究開発の動向
中村 保
The amount of production orders from Japa-
nese car and construction machine industries
have slightly increased in 2002, but the costs of
the forged parts have decreased due to severe
-
12 論 文 抄 録
competitions with the other Asian countries.
Most of the forging industries and some univer-
sities are making more efforts for technological
researches and developments to meet the de-
mand for higher accuracy and higher quality
products, shortening of delivery time, and de-
velopment of forged parts for new industrial
fields. Some helical gears of which surfaces can
be net-shaped have been started for commercial
base production to be shipped to car industries.
Some non-graphite lubricants for hot forging
and some conversion coating free lubricants for
cold forging have been developed to improve
some environmental problems.
[Proceedings of the 8th ASPF, pp. 123-127 (2003)]
Strength Evaluation of Aluminum Alloy Bold
by Nano-Indentation Hardness Test
Yoshihiro Kubota, Tamotsu Nakamura,
Mitsuo Kobayashi, Katsumi Fukuda
ナノ硬さ試験によるアルミニウムボルトの強度評価
久保田義弘、中村 保、小林光男、福田克己
Aluminum alloy bolts are used to joint two or
more aluminum space frames. Such aluminum
alloy bolts are required high strength. A high
strength aluminum alloy bolt (7050, T7 temper)
has been developed by the authors. The bolt
has a small grain size in all area of the bolt by
thermo-mechanical treatment. Moreover, the
ductility and stress corrosion cracking resis-
tance have been improved by over aging treat-
ment by T73 temper treatment. Recently, a
nano-indentation hardness has been developed
to evaluate the hardness in microscopic area. In
the present paper, the distribution of
nano9indentation hardness of microscopic grain
structure in the high strength aluminum alloy
bolt has been measured by nano-indentation
hardness tester.
[J. Material Testing Research Association of Ja-
pan, Vol. 48, No.4, pp. 232-236 (2003)]
FEM Analysis of Contact Mechanism in
Press-Forming of Lubricant Pre-Coated
Steel Sheet
Zhrgang Wang, Tamotsu Nakamura,
Kuniaki Dohda, Toshihiro Obika
潤滑処理鋼板のプレス成形における
接触機構のFEM解析
王 志剛、中村 保、堂田 邦明、小比賀俊博
This paper describes the contact situation be-
tween the die and the lubricant pre-caoted steel
sheet in the press-forming by using FEM simu-
lation. The FEM simulation is carried out by
supposing that the lubricant pre-coated steel
sheet consists of the lubrication layer and thick
galvanized layer. Both the lubrication layer and
galvanized layer are assumed as rigid-plastic
material. The variations in the contact situation
between the die and the lubricant pre-coated
steel sheet are investigated by changing the
friction coefficient between the die and lubrica-
tion layer, the thickness and hardness of lubri-
cation layer, the velocity ratio of the relative
sliding velocity to pressing velocity, etc. The
simulated results show that the contact area is
influenced by the average contact pressure, the
velocity ratio, the thickness of lubrication layer,
and friction coefficient.
[J. of Materials Processing Technology, Vol. 140.
pp. 514-519 (2003)]
鍛造におけるトライボロジー
中村 保
Tribology in Forging
Tamotsu Nakamura
鍛造のトライボロジー技術は、摩擦管制、製品表面
仕上げ向上、焼付きや工具摩耗防止等の要求から必要
不可欠であると考えられてきた。しかし、最近はとく
に環境負荷の大きな潤滑剤の使用は極力避けることが
要求されている。究極的には、潤滑剤なしで塑性加工
-
13論 文 抄 録
を実現することが理想的であるが、現状では、そこに
至るまでの過程において、環境負荷を軽減するための
種々のトライボロジー技術が提案され、すでに実用化
が進んでいる。
[プレス技術, 41巻, 12号, pp. 51-55 (2003)]
AEのフラクタル性を用いた鍛造用金型の
損傷・破壊の検出
早川邦夫、中村 保、米澤英樹、田中繁一
本論文では、アコースティック・エミッション (AE)
のフラクタル性を利用した工具損傷の予知技術の確立
のための基礎として、繰返し冷間押出し加工工程にお
ける金型のAEによる損傷・破壊の検出を試みた。金型
の損傷状態の評価には、AE振幅分布のフラクタル解析
により得られるフラクタル次元の変化を追跡すること
により行う。
まず、AE振幅分布のフラクタル性について説明し、
つづいて、本研究で用いる金型材料SKD11の引張り破
壊試験を行い、SKD11の変形および破壊に起因する
AE振幅分布特性のフラクタル特性を調べる。その結果、
それぞれのフラクタル次元として1.97および1.44で
あった。
続いて、繰返し押出し実験を行い、そのフラクタル
次元の変化を調べた。潤滑剤として、被加工材に化成
被膜処理を施した。300回の繰返しにおいて、金型に損
傷や摩耗は観察されず、AE振幅分布のフラクタル次元
はほとんど変化せず平均値として2.04であった。
つぎに、金型損傷を促進させた試験を、潤滑剤とし
て鉱物油とステアリン酸の混合物を用いて行った。繰
返し数101回において、被加工材に欠陥が観察され、金
型肩部半径にき裂の発生が認められた。その前後での
フラクタル次元の平均はそれぞれ2.01および1.52で
あった。以上より、フラクタル次元は金型の損傷の進
行の指標として有効であることがわかった。
最後に、Kaiser効果を用いて金型起因のAEと被加
工材変形および摩擦起因のAEとを分離する手法を提
案した。
[塑性と加工, 44巻505号, pp. 72-76 (2003)]
FE Analysis of Interfacial Behavior of Cold
Forging Tool Coated by Hard Film Using
Interfacial Spring Model with Damage
Mechanics
K. Hayakawa, T. Nakamura,
K. Harada and S. Tanaka
A behavior of interface of cold forging tool
coated by hard film is analyzed by FEM. Me-
chanical properties of the interface between
hard film and the tool material is modeled under
the framework of the irreversible thermody-
namic constitutive equations theory with con-
tinuum damage mechanics. The interfacial
damage variable and its evolution law are in-
troduced, which expresses the degradation of
the interface. The indentation of a hemispheri-
cal tool of SUJ2 in JIS coated by electroplated
coating of chromium into a cylindrical work-
piece of S25C in JIS is performed to examine the
validity of the proposed model. In FE analysis,
the proposed constitutive equations are imple-
mented by the non-linear springs between the
opposite nodes of the interface. Calculated re-
sults show that the maximum interfacial normal
displacement is seen at an immediately forward
from the lip of the indentation, whereas maxi-
mum interfacial tangential displacement is seen
the immediately backward of the lip of the in-
dentation. The region where the debonding will
first onset by the calculated results, shows the
good agreement with the behavior of the chro-
mium electroplated forging tool actually oper-
ated. Finally, a method for evaluating the inter-
facial debonding life of coated tool is proposed.
[4th International conference on industrial tool,
pp. 411-418 (2003.4)]
事故事例に学ぶ接合・複合-その2-
白井秀明、吉田一也、佐野村幸夫、
早川邦夫、桜井冨美夫
製造品によるさまざまな事故は、発生当初は大きく
報じられるがその調査結果や事故防止対策は長い期間
-
14 論 文 抄 録
の後報告書等の形でまとめられその扱いは大きくない。
本論文は、日本塑性加工学会 接合・複合分科会 事
故事例研究班による、スポーツ用具および日用品によ
る接合・複合に関する事故とその後事故防止対策に対
する調査結果を解説したものである。スポーツ用品か
ら5例、日用品から5例の事故の様子とその後の対策
について紹介し、その社会的および技術的からの解説
をおこなった。
[塑性と加工, 44巻512号, pp. 922-927 (2003)]
FE ANALYSIS OF INTERFACIAL BEHAVIOR
OF COLD FORGING TOOL COATED
BY HARD FILM
Kunio HAYAKAWA
A behavior of interface of cold forging tool
coated by hard film is analyzed by FEM. The
indentation of a hemispherical tool of SUJ2 in
JIS coated by electroplated coating of chromium
into a cylindrical workpiece of S25C in JIS is
performed. The proposed constitutive equa-
tions are implemented by the non-linear springs
model at the interface. Calculated results show
that the maximum interfacial normal displace-
ment is observed at an immediately forward
from the lip of the indentation, whereas maxi-
mum interfacial tangential displacement is at the
immediately backward of the lip of the indenta-
tion.
[8th Asian Seminar of Precision Forging, pp.
18-21 (2003.10)]
傾斜機能材料のレーザフラッシュ法による
熱物性値測定と評価
大谷晃弘、吉田豊明、藤沢良昭、唐大偉、荒木信幸
Measurement and Evaluation of
Thermophysical Properties of FGM by Laser
Flash Method.
A. Ohtani, T. Yoshida, Y. Hujisawa,
D. W. Tang, N. Araki
FGMの遮熱性能や熱移動特性を評価するには、熱物
性値分布と非定常温度応答との関係を明確にし、熱物
性値やその分布の測定・評価手法を確立しなければな
らない。本研究では、FGM (層状) の温度応答をレー
ザフラッシュ法を用いて測定し、熱拡散率および熱伝
導率を評価する方法について検討を行った。FGM試料
としてCuとNiおよびその合金から構成され4層試料
を用いた。また、計算にはパルス状加熱による多層試
料の温度応答の解析解を用いた。
FGMの温度応答の測定結果及び計算結果は、試料裏
面の最高温度上昇の1/2に達するまでの時間t1/2を一致
させた均質材料に対するParkerの式による温度応答
とよく似ているので、温度応答の形からFGMと均質材
料を区別するのは困難である。このことより、FGMの
温度応答を均質材料と同様に扱いt1/2法を用いて熱拡
散率を求めることは意味あるものと考え、この熱拡散
率はFGMの相当熱拡散率とみなしてもよいことを提
案した。
[傾斜機能材料論文集 (FGM2002), pp. 62-66 (2002)]
GHP排熱を駆動熱源とする
シリカゲル-水吸着サイクルによる冷房強化
(吸着器モデルにおける
熱および物質移動特性の最適化)
本間寛己、荒木信幸
Augmentation of Cooling Output by Silica
Gel-Water Adsorption Cycle Utilizing the
Waste Heat of GHP
(Optimization of Heat and Mass Transfer
Characteristics for Adsorber Model)
H. Homma and N. Araki
GHPの排熱を駆動熱源として利用することを想定
したシリカゲル-水吸着サイクルの高効率化には、吸
着剤における熱および物質移動の向上が必要となる。
本研究では吸着器のモデルとしてユニットモデルを製
作した。ユニットモデルとは、実際には大型で多数の
伝熱管が取り付けられる吸着器を、小型で一本の伝熱
管のみを用いる吸着器にしたものである。また、シリ
カゲルを表面に接着した一本の伝熱管をユニットセル
と名付け、このユニットセルの熱および物質移動特性
の最適化について実験的および解析的に検討を行った。
[日本冷凍空調学会論文集, Vol. 20, No. 2, pp.
143-154 (2003)]
-
15論 文 抄 録
Dynamical Thermoelastic Behavior Predicted
by an Extended Lord-Shulman Theory
D. W. Tang and N. Araki
拡張されたLord-Shulman理論による
動的熱弾性挙動
唐 大偉、荒木信幸
The extended form of Lord-Shulman (L-S)
theory is formulated by the Jeffreys type heat
conduction equation at first. The combined
constitutive equations of the generalized ther-
moelastic theories, including the L-S theory, the
Green-Lindsay (G-L) theory and the extended
L-S theory, are given. The equations in the ex-
tended L-S and G-L cases are solved by the nu-
merical inversion of Laplace transform for the
Danilovskaya’s problem. The temperature and
strain fields in the semi-infinite elastic medium
are calculated for various relaxation parameters
and thermo-mechanical coupling factor. Vari-
ous propagating characteristics of the thermal
and elastic waves are discussed.
[JSME Int. Journal, A46, pp. 126-130 (2003)]
NUMERICAL MODELING FOR
THREE-DIMENSIONAL HEAT AND FLUID
FLOW THROUGH A BANK
OF CYLINDERS IN YAW
A. Nakayama, F. Kuwahara and T. Hayashi
Department of Mechanical Engineering,
Shizuoka University
3-5-1 Johoku, Hamamatsu, 432-8561 Japan
斜めに置かれた管群を横切る三次元流れと
熱流動の数値モデリング
中山 顕、桑原不二朗、林 朋博
A numerical model for a three-dimensional
heat and fluid flow through a bank of infinitely
long cylinders in yaw has been proposed to in-
vestigate complex flow and heat transfer char-
acteristics a ssociated with manmade structures
such as extended fins and plate fins in heat
transfer equipment. Upon exploiting the peri-
odicity of the structure, only one structural unit
has been taken as a calculation domain. An
economical quasi-three-dimensional calcula-
tion procedure has been proposed to replace
exhaustive full three-dimensional numerical
manipulations. It has been shown that, under
macroscopically uniform flow, the three-di-
mensional governing equations reduce to
quasi-three-dimensional forms, in which all de-
rivatives associated with the axis of the cylinder
can be either eliminated or replaced by other
determinable expressions. Thus, only two-di-
mensional storages are required for the depen-
dent variables in question. Extensive numerical
calculations were carried out for various sets of
the porosity, degree of anisotropy, Reynolds
number and macroscopic flow direction in a
three-dimensional space. The numerical results
thus obtained for periodically fully-developed
flow and temperature fields were integrated
over a structural unit to determine the perme-
ability tensor, Forchheimer tensor and direc-
tional interfacial heat transfer coefficient, to
elucidate the effects of yaw angle on these
macroscopic flow and heat transfer characteris-
tics. Upon examining these numerical data, a
usefull set of explicit expressions have been es-
tablised for the permeability tensor, Forch-
heimer tensor and directional interfacial heat
transfer coefficient to characterize flow and heat
transfer through a bank of cylinders in yaw.
[Journal of Fluid Mechanics, Vol. 498, pp.
131-159 (2004)]
-
16 論 文 抄 録
Criterion to evaluate the stability of Nd
sintered magnets for refrigerant compressor
motors
Tadashi Yanagisawa, Mitsuhiro Fukuta,
Tadashi Iizuka, Akihiko Ishiyama, Masami Wada
and Yuko Ohtani
冷媒圧縮機モータ用Nd焼結磁石の
安定性を評価するための基準
柳沢 正、福田充宏、飯塚 董、石山明彦、
和田正美、大谷裕子
This paper concerns the stability of Nd
(neodymium) sintered magnets used for
high-efficiency DC motors in refrigerant com-
pressors. Many kinds of Nd sintered magnets
with and without surface treatment were sub-
jected to the aging test of 140℃ and 1440 hours
under three different atmospheric conditions of
refrigerant, oil, moisture content and vacuum
level. Mechanical and magnetic properties of
the magnet were examined, and chemical char-
acteristics of the oil and refrigerant were also
analyzed. As a result, most of the tested magnets
retained the satisfactory properties after the ag-
ing test, but some magnets without surface
treatment showed deterioration in magnetic
properties. The deterioration was larger under
the condition with higher moisture content.
Concerning the oils and refrigerants, no re-
markable change in their chemical characteris-
tics was observed after the aging test. The test
conditions employed in this study become one
of the evaluation criteria of the Nd sintered
magnets.
[日本冷凍空調学会論文集、Vol. 20 No. 2, pp. 265-272
(2003)]
Performance characteristics of air cycle heat
pumps working with moist air
Tadashi Yanagisawa, Mitsuhiro Fukuta,
Yasuhiro Ogi and Kiyoshi Sawai
湿り空気で作動する空気サイクルヒートポンプの
性能特性
柳沢 正、福田充宏、小木康弘、澤井 清
As the environmental issues become serious
due to synthetic refrigerants used for refrigera-
tion and heat pump systems, the use of natural
substance as refrigerant, so-called natural re-
frigerants or natural working fluids, is expanding
in many systems. The potential natural working
fluids are hydrocarbon, carbon dioxide, am-
monia, water, air and so on. In this study, an air
cycle heat pump water heating system using air
as a working fluid is focused, and the ways to
improve its performance are discussed. As one
of the ways, we propose to use moist air instead
of dry air and its performance characteristics are
examined theoretically. As a result, heating ca-
pacity and the expansion power increase with
the increase of the humidity ratio at the com-
pressor inlet, which leads to the improvement of
the cycle coefficient of performance. The heat
pump water heating system working with moist
air can be one of promising applications of the
air cycle.
[Proceedings of 21st International Congress of
Refrigeration, Paper No. ICR0229, pp. 1-7, (2003)]
Expansion type air dryer for compressed air
Tadashi Yanagisawa, Mitsuhiro Fukuta and
Yasuhiro Ogi
圧縮空気用の膨張形エアドライヤ
柳沢 正、福田充宏、小木康弘
There are many types of air dryers for com-
pressed air such as refrigeration type, adsorp-
tion type and so on. In this study, a new type of
-
17論 文 抄 録
air dryer is proposed using an expander which
works with compressed air and produces low
temperature, low humidity air easily. Perfor-
mance characteristics of the expansion type air
dryer are investigated theoretically. Many types
of expander arrangements including the con-
ventional air cycle are possible, but the most
promising ones are the expander-compressor
and compressor-expander combinations work-
ing with the compressed air. The dryers can
achieve a pressurized dew point of 10 ℃ with
work less than 10 % of the isentropic air-com-
pression energy.
[IMechE Conference Transactions, Interna-
tional Conference on Compressors and their
Systems, C615, pp. 349-358, (2003)]
Performance prediction of vane type expander
for CO2 cycle
Mitsuhiro FUKUTA, Tadashi YANAGISAWA and
Reinhard Radermacher
CO2サイクル用ベーン形膨張機の性能予測
福田充宏、柳沢 正、Reinhard Radermacher
Carbon dioxide (CO2) is one candidate of al-
ternatives to HFC refrigerants for refrigeration
or heat pump cycles. Since the inherent COP of
an air-cooled CO2 cycle is lower than that of
HFCs, both compressors and the cycle perfor-
mance should be improved. The most promis-
ing method for improving the performance of
CO2 cycle is to recover throttling loss by using
an expander as an expansion device. In this
study, a vane type expander is considered. The
expansion process from super-critical condition
to two-phase one in the expander and the per-
formance of the expander are analyzed with a
mathematical model. Although a large expan-
sion volume ratio is not achievable with the
vane type expander, decrease of the perfor-
mance due to the small expansion ratio is ac-
ceptable. The influence of leakage on the per-
formance of vane expander is dominant, while
the heat transfer from the expander body to the
fluid has relatively small influence on the per-
formance.
[Proceedings of 21st International Congress of
Refrigeration, Paper No. ICR0251, pp. 1-8, (2003)]
ベーン形圧縮機におけるベーン背圧とその計算モデル
福田充宏、柳沢 正、井尻 誠、依田誠一郎
Vane back-pressure of vane type compressor
and its mathematical model
Mitsuhiro Fukuta, Tadashi Yanagisawa,
Makoto Ijiri, Seiichiro Yoda
ベーン形圧縮機ではベーンとステータの離間現象を
防ぐために吐出し圧力を利用してベーン背部空間を昇
圧しているが、圧力が高すぎるとベーン先端の摩擦や
摩耗を引き起こすため、適正な圧力とする必要がある。
本研究ではベーン形圧縮機のベーン背圧予測モデルの
構築を目的とし、ベーン背部空間につながる空間の可
視化およびベーン背圧の測定を様々な条件で行い、計
算値との比較を行った。その結果ベーン背部空間には
圧縮室側から冷媒ガスが漏れ込んでいること、ロータ
端面の漏れ流れはロータ外周の時間平均圧力分布を用
いてモデル化できることなどを示し、ベーン形圧縮機
のベーン背圧計算のモデル化の指針を得た。
[日本冷凍空調学会論文集、20巻、3号、pp. 375-385,
(2003)]
Influences of miscible and immiscible oils on
flow characteristics through capillary
tube-part I: experimental study
Mitsuhiro Fukuta, Tadashi Yanagisawa,
Toshinori Arai and Yasuhiro Ogi
キャピラリーチューブを通る流動特性に及ぼす相溶油
および非相溶油の影響-第1報:実験的研究
福田充宏、柳沢 正、新井聡経、小木康博
A capillary tube is widely used as an expan-
sion device for small refrigeration cycles. In a
practical refrigeration cycle, some amount of
refrigeration oil is discharged from a compres-
-
18 論 文 抄 録
sor and refrigerant/oil mixture flows through the
capillary tube. This study investigated experi-
mentally the influence of mixing of the refrig-
eration oil with the refrigerant on the flow
through the capillary tube. The experiments are
carried out with not only a miscible combination
of refrigerant and oil but also an immiscible
combination. In both cases, the mass flow rate
through the capillary tube and temperature and
pressure distributions along the tube are mea-
sured under several conditions of subcooled
degree and oil concentration. In the case of
miscible combination, the mass flow rate of re-
frigerant decreases with increasing the oil con-
centration because the viscosity of liquid phase
increases by the mixing of viscous oil. Even in
the case of the immiscible combination, the oil
droplet is so small that it mixes homogeneously
in the liquid phase in the capillary tube and the
refrigerant mass flow rate decreases by the
mixing of immiscible oil. There is no significant
influence of the oil concentration on the under-
pressure, which means pressure difference be-
tween saturation pressure and flash inception
pressure, in both miscible and immiscible com-
binations.
[Int. J. of Refrigeration, Vol. 26, No. 7, pp.
823-829, (2003)]
New Predictive Display Method of Motion and
Force Information for Network Teleoperation
Without Using Virtual Environment Model
Tomotaka Itoh, Koji Yudate, Shinsuke Ito and
Takashi Matsui
ネットワークテレオペレーションのための環境モデル
を要しない力と運動の新しい予測呈示手法
伊藤友孝、弓達孝治、伊藤真介、松井 隆
This paper proposes an alternative predictive
display method for a network teleoperation with
the time delay. In general, the communication
time delay in a teleoperation system disturbs not
only the stability of the robotic system but also
that of the human controlled loop and it leads to
a decrease of the reality of the operation. To
prevent this, several predictive display ap-
proaches based on the virtual environment
models have been proposed recently. But, they
cannot work well without the precise virtual
environment model and, in addition, it is a
complicated and time-consuming task to con-
struct the precise kinematic and dynamic model
of the general various working environment. In
this paper, we will design a new predictive dis-
play method of the motion and the force infor-
mation for a general network teleoperation
without using the virtual environment model.
The proposed method is basically based on the
superimposed display of the predictive image
and the real image of the slave site. The major
contribution of this method is to provide the
predictive motion and force information to the
human operator without using any virtual model
of the real environment even in the constrained
space as well as in the free space. It enables to
construct the environment- independent and
easily applicable teleoperation system in the
field of the network robotics such as the
tele-manipulation, tele-communication,
home/hobby- use-network-teleoperation and
so on. The proposed method is experimentally
applied to a tele-manipulation system and the
results illustrate the validity of the proposed ap-
proach.
[Proc. IEEE/RSJ International Conference on
Intelligent Robots and Systems (2003.10)]
Low-Temperature Sterilization with
Surface-Wave-Excited Oxygen Plasma
M. Nagatsu, F. Terashita and Y. Koide
表面波励起酸素プラズマを用いた低温滅菌
永津雅章、寺下文恵、小出幸夫
Low-temperature plasma sterilization has
been experimentally demonstrated using
surface-wave plasma excited by a 2.45 GHz mi-
-
19論 文 抄 録
crowave. With the spores of Bacillus stearothermo-
philus and Bacillus subtilis as biological indicators,
we have carried out the plasma sterilization ex-
periments by varying the irradiation period of
oxygen plasma discharges. It was experimen-
tally confirmed that the spores with a population
of 1.5x106 were sterilized by irradiating them with
oxygen plasma discharges generated with a mi-
crowave power of 700 W at a pressure of 60-80
mTorr for 3 minutes or longer. From the SEM
analysis of the spores, we found that the steril-
ized spores clearly had different sizes and
shapes compared with those before the plasma
irradiation. Furthermore, present experiments
suggested that the changes of spore shapes were
mainly attributed to the reactive interactions
with oxygen radicals.
[Jpn. J. Appl. Phys., Vol. 42, No. 7B, pp.
L856-L859 (2003)]
The prospect on the use of beryllium mirrors
in a fusion reactor with beryllium first wall
A.F.Bardamid, A.I.Belyayeva, V.N.Bondarenko,
N.G.Elistratov, A.A,Galuza, V.G.Konovalov,
M.Nagatsu, I.V.Ryzhkov, A.N.Shapoval,
A.F.Shtan, S.I.Solodovchenko, A.A.Vasil’ev,
V.S.Voitsenya and A.M.Zimin
Be第一壁を用いる核融合炉における
Beミラー使用に関する考察
A.F.Bardamid, A.I.Belyayeva, V.N.Bondarenko,
N.G.Elistratov, A.A,Galuza, V.G.Konovalov,
永津雅章, I.V.Ryzhkov, A.N.Shapoval, A.F.Shtan,
S.I.Solodovchenko, A.A.Vasil’ev, V.S.Voitsenya
and A.M.Zimin
Many methods of plasma diagnostics in a fu-
sion reactor (FR) require the use of so called
first mirrors (FM) disposed inside the vacuum
vessel. One reason of FM degradation is the
deposition on the FM surface of material eroded
from the inner components subjected to most
intensive plasma impact, i.e., deposition of be-
ryllium in the case of experimental FR (ITER)
with Be wall protection. Thus, in ITER only Be
mirror can sustain its optical properties for long
time and in the present paper results are pre-
sented of the simulation experiments on some
ITER environment effects on FM made of Be.
Namely, effects of bombardment by D ions on
reflectance, R (l), in the l=220-650 nm range
was studied as modelling the impact of charge
exchange atoms.
It was found that with high ion energy
(600-1350 eV) the sharp drop of R (l) , 5-20 %,
rising with decreasing wavelength of reflected
light, was observed after ion fluence ~
1018ions/cm2. It was supposed that under deute-
rium ions the BeO surface film was transformed
into the Be (OD)2 film accompanying by chang-
ing the refraction and extinction indices of the
film, as was registered by ellipsometry mea-
surements. Effects of ion energy and ion fluence
variation on R (l) of Be mirrors are discussed in
detail.
[Problems of Atomic Science and Technology,
series Plasma Physics (9), No. 1 (2003) pp. 52-55]
Production of Large-Area Microwave Plasma
and its Application to Plasma Chemical Vapor
Deposition
M. Nagatsu
大面積マイクロ波プラズマの生成と
そのプラズマCVDへの応用
永津雅章
Microwave plasmas in low-pressure and
high-pressure regions have been studied for
aiming at developing the large-area plasma and
at applying them to plasma CVD. The large-area
surface-wave plasma (SWP) has been utilized
for the large-area deposition of amorphous car-
bon (a-C) film or carbon nanotube (CNT) .
The characteristics of field emission of a-C films
and CNT prepared with the SWP are investi-
gated. Film characteristics measured with X-ray
photoelectron spectroscopy, Fourier
transform-infrared spectrophotometry, Raman
spectroscopy and atomic force microscope are
-
20 論 文 抄 録
presented.
Recent results of relatively high-pressure mi-
crowave plasmas for diamond film synthesis
have been also introduced. Especially, the mi-
crowave plasma CVD reactor with a pair of mi-
crowave launchers, where an additional micro-
wave launcher is installed at the substrate side,
has been demonstrated in order to show a pos-
sibility of enlarging the plasma discharge. The
electric field analysis has been also carried out
to design the optimum microwave launcher us-
ing the finite difference time domain (FDTD)
method.
Lastly, new type of large-area microwave
plasma device, where a planar cylindrical mi-
crowave launcher is installed inside the vacuum
chamber, is described together with preliminary
results.
[Proc. of 5th Int. Workshop on Microwave Dis-
charges (special edition), 2003]
C6211DSKによるCDMA通信
デモンストレーション装置
犬塚 博、福田雅也、小野 努、萩村将幸、増田征司、
齋藤禎仁、水野保則
Demonstration of CDMA communications by
TMS320C6211DSK
Hiroshi Inuzuka, Masaya Fukuta, Tsutomu Ono,
Masayuki Hagimura, Masashi Masuda,
Yoshihito Saito and Yasunori Mizuno
近年、携帯電話は日常生活の中で益々当たり前の物
となってきている。その通信方式としてスペクトラム
拡散通信技術を用いた直接拡散 (DS: Direct se-
quence) -CDMA (Code Division Multiple Ac-
cess) を採用した携帯電話も多く使われる様になって
きており、それらを発展させたWideband-CDMA技
術を採用したサービスも2001年から開始された。この
様な携帯電話は高校生・大学生にとって無くてはなら
ないアイテムとなってきているが、反面、その中身や
原理については益々ブラックボックス化される傾向に
あり、原理への関心は逆に薄れてきていると言える。
そこで、その様な高校生・大学生から小中学生の子供
達を対象にその原理を示す実験を簡単に行えるように、
CDMA通信のデモンストレーションを行う装置を製
作した。近年、大学等の高等教育機関は単にそこに所
属する学生を教育するのみならず、近隣の人々や地元
企業のエンジニアの啓発・教育等も要求される時代と
なってきており、そ�