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ENGINEERING NEWS IN BRIEF
E-Mail Newsletter
No.89
Issued by the Asian TOP Panel, May 2009
The Chinese Mechanical Engineering Society
(CMES)
The Institution of Engineers, Indonesia (PII)
The Japan Society of Mechanical Engineers
(JSME)
The Korean Society of Mechanical Engineers
(KSME)
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According to the agreement
made in the 2nd Asian TOP Panel Meeting,
the ENGINEERING NEWS IN BRIEF (E-mail newsletter)
has now been edited
by the JSME for the year 2009.
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[Contents]
1) Recycling Method for Initial Type of Aluminum
Rolling Stock (Source: JSME)
2) Noise Absorbing Sponge Technology (Source:
JSME)
3) Materials Inspection and Evaluation Using (Source: JSME)
4) Hardness Tester Digitalizing Softness (Source:
JSME)
5) Disassembly Sequence Planning Based on Generalized
Axis Theory(Source: CMES)
6) Analysis and Optimization of the Internal
Flow in Centrifugal Compressor Volute
(Source: CMES)
7) Technology on Large Scale Numerical Control
Machine Tool Condition Monitoring Based
on Built-in Sensors(Source: CMES)
8) Effect of Imperfections on the Mechanical
Behavior of Wire-woven Bulk Kagome Truss
PCMs under Shear Loading (Source: KSME)
9) A Comparison of Residual Stresses in Built-up
Steel using Hole-drilling Method (Source: KSME)
10) Modeling of a Magneto-rheological (MR) Fluid
Damper using a Self Tuning Fuzzy Mechanism
(Source: KSME)
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1) Recycling Method for Initial Type of Aluminum
Rolling Stock
Masao Tomeoka, Tokyo Metro Co., Ltd
In order to establish the recycling method
for initial type of aluminum rolling
stock,
authors estimated the component of
secondary
aluminum alloy melted from out-of service
aluminum car-body.
To recycle the initial type of aluminum rolling
stock which is structured by welding
many
kinds of aluminum alloy, it is necessary
to classify into each type of aluminum
alloy.
Because the method of extracting the
alloy
elements except aluminum is not established
commercially. So, authors scrap the
aluminum
rolling stock and confirm the composition
of that secondary aluminum alloy.
As the result, yield rate of this scrap is
86.2%. And it is confirmed to turn
this scrap
on directly to the operating furnace,
even
though it contains 4.0% volume content
of
iron and the stainless steel. Finally
the
under-frame reproduction alloy with
a high
content of zinc is recycled to ADC12.
The
roof and side-plate with a low content
of
zinc is recycled to AC2C which is changed
into engine component (cylinder head,
intake
manifold etc.)
________________________________________________________________________________________________________________________________
2) Noise Absorbing Sponge Technology
Naoki Yukawa, Sumitomo Rubber Industries,
Ltd.
In Japan, In January, 2006, Sumitomo Rubber
Industries released a tire with sponge which
absorbed a noise of the tire inside.
By this technology, we succeeded in reducing
a cavity resonance by the resonance
of the
air of the tire inside that had difficulty
with reduction till now.
It was difficult for the tire with the sponge
to achieve many performance ? durability,
heat-resistant, reliability, weatherability,
strength - found on a tire till now.
However, we succeeded in mass production
for the first time in the world by
developing
appropriate material and shape.
By adopting this technology with our existing
noise reduction technology, I was able
to
give a tire the innovative quietness
and
new sense of values.
_________________________________________________________________________________________________________________________________
3) Materials Inspection and Evaluation Using
Hironori Tohmyoh, Tohoku University
This article reports an acoustic technology
called dry-contact acoustic microscopy
for
performing the high-resolution acoustic
imaging
of a sample under the dry environment.
The
dry-contact technique performs the
transduction
of broadband, high-frequency ultrasound
via
a solid layer inserted between water
and
the sample, whereat the pressure of
about
0.1 MPa is applied at the layer/sample
interface
by evacuating air between them. Typically,
the polymer films are used as the intermediate
layer for water protection, and the
film
sometimes behaves as frequency filter
for
signal amplification or modulation.
This
is brought by the acoustic resonance
phenomenon
among water, film and the sample, and
can
be an advantage of the technique for
getting
high quality acoustic images of the
testing
samples. Moreover, by analyzing the
acoustic
resonance phenomenon among the three
media,
the acoustic properties of the freestanding
thin polymer film, i.e., the acoustic
impedance,
velocity and density, can precisely
be measured
by the dry-contact acoustic microscope.
_________________________________________________________________________________________________________________________________
4) Hardness Tester Digitalizing Softness
Tadashi Mitsuhashi, Citizen Seimitsu Co.,
Ltd.
Energy-absorption material, foods, and so
on are too soft to apply conventional standards
of rubber hardness.
Since measuring force can be set to
minimum of 2mN utilizing voice coil motor
systems, this product can respond to various
needs.
_________________________________________________________________________________________________________________________________
5) Disassembly Sequence Planning Based on Generalized
Axis Theory
Tian Ying, Wang Taiyong, He Gaiyun, Ding
Baihui,
Tianjin University
How to obtain the compact and reasonable
expression of all feasible disassembly
paths
has become the most important problem
to
be resolved in disassembly sequence
planning.
In order to optimize the sub-assembly
clustering
in planning of disassembly path, and
to avoid
combination explosion problem of calculation
caused by traditional method, a theory
of
generalized axis conformed with the
engineering
semantic information and the concept
about
disassembly priority adjustment coefficient
are put forward, considering the information
about assembly structure and assembly
process,
quoting and extending the concept of
matching
relation which express the compact
degree
between parts. On operation procedure,
it’s
first to gain the coaxial membership
matrix
and its modified matrix by using the
expression
form of adjacency matrix, the coaxiality
coefficient function and the disassembly
priority distributing table. Then,
it can
be obtained considering related algorithms
of fuzzy cluster analysis of transitivity
fuzzy equivalent matrix and ? dynamic product clustering relationship
graph. Using these, the sub-assembly
clustering
can be obtained in the end. The benefit
of
the proposed theory and method is illustrated
through an example, which can improve
the
consistence with the actual engineering
situation,
and calculating work can be greatly
reduced.
Key words: generalized axis theory; sub-assembly; disassembly
sequence planning; fuzzy clustering_________________________________________________________________________________________________________________________________
6) Analysis and Optimization of the Internal
Flow in Centrifugal Compressor Volute
Ji Chunjun, Wang Yajun, Wang Xuejun, Yao
Lixin
Dalian University of Technology
The 3D internal viscous flow in the last
stage of a centrifugal compressor is
analyzed
numerically with commercial computational
fluid dynamic software NUMECA. The
geometric
model includes the close-type impeller,
the
vaneless diffuser and the volute. Based
on
the analytic results, modifications
to the
constant width volute are proposed
and the
stage efficiency is increased by 4.5%.
The
same approach is applied on the last
stage
of another centrifugal compressor and
the
efficiency is also increased by 4.5%.
Through
summing up the effect of different
parameters,
the code for the aerodynamic design
of the
welding type volute is developed. The
code
is tested on another compressor with
a constant
height volute and the last stage efficiency
is increased by 3%. Numerical experiments
prove that the code can be used for
the aerodynamic
design of all welding type volutes.
Key words:centrifugal compressor; welding type volute;
numerical simulation; efficency
________________________________________________________________________________________________________________________________
7) Technology on Large Scale Numerical Control
Machine Tool Condition Monitoring
Based on Built-in Sensors
Zhou Yuqing, Mei Xuesong, Jiang Gedong, Sun
Nuogang, Tao Tao
Xi’an Jiaotong University
A kind of large scale numerical control (NC)
machine tool condition monitoring system
based on AC servo motor encoder, linear
or
rotary scale and motor current (torque)
is
proposed. To obtain the state information,
the test principles of motor torque,
machine
tool position and lubrication characteristic
are profoundly investigated, and some
different
sampling methods for open NCs and commercial
NCs are suggested. Furthermore, some
constant
speed tests and lubrication characteristic
tests are carried out respectively.
The analysis
shows that it is feasible and reliable
to
use the motor current, position, instantaneous
velocity, instantaneous acceleration
for
monitoring the mechanical parts state
and
evaluating the servo control characteristics,
which lays the foundation for large
scale
numerical control machine tool on-line
condition
monitoring and fault diagnosis.
Key words: NC machine tool; built-in sensors; condition
monitoring; fault diagnosis
_________________________________________________________________________________________________________________________________
8) Effect of Imperfections on the Mechanical
Behavior of Wire-woven Bulk Kagome
Truss PCMs under Shear Loading
Sangil Hyun1, Ji-Eun Choi2 and Ki-Ju Kang3
1.Simulation Center, Korea Inst. of Ceramic
Eng. & Tech.,
2.Automobile Research Center, Chonnam National University,
3. School of Mechanical Systems Engineering,
Chonnam National University
Abstract Wire-woven bulk kagome (WBK) materials are
a new class of cellular metallic structures
possessing desired mechanical performance
and can be fabricated easily by assembling
metallic wires. In previous studies,
the
WBK materials were shown to have high
strength
and weak sensitivity on imperfections
under
compressive loads. In this paper, we
present
numerical simulation results on the
mechanical
performance of WBK and its sensitivity
on
imperfections under shear loads. Two
types
of statistical imperfections on geometry
and material property were introduced
in
the simulation models as likewise the
previous
studies. The simulation results were
compared
with the experimental measurement on
the
WBK made of stainless wire (SUS304).
The
WBK were shown to have a good isotropic
mechanical
strength under various orientations
of shear
loadings.
Keyword:Cellular metal-PCM (Periodic Cellular Metal)-Kagome
truss-Imperfections-PBC (periodic boundary
condition)-Random network analysis
9) A Comparison of Residual Stresses in Built-up
Steel using Hole-drilling Method
M.A.Nawafleh1, Y.M.Hunaiti2 and R.M.Younes3
1. Department of Civil Engineering, Al-Hussein
Bin Talal University,
2. Department of Civil Engineering, University
of Jordan,
3. Department of Civil Engineering, Tafila
Technical University,
Abstract Residual stresses have a significant effect
on the stability resistance of metal
building
systems. An experimental program was
conducted
to measure these stresses in built-up
steel
beams using incremental hole-drilling
method.
The experimental results reveal that
the
predicted residual stress type of pattern
for built-up I-sections with fillet
welds
on one side of the web is not the same
as
the pattern of residual stresses in
built-up
I-sections with fillet welds on both
sides
of the web.
Keyword: Beams-Residual stresses-Hole-drilling-Steel
10) Modeling of a Magneto-rheological (MR)
Fluid Damper using a Self Tuning Fuzzy
Mechanism
Kyoung Kwan Ahn1, Dinh Quang, Truong1 and Muhammad AminulIslam1
1. School of Mechanical and Automotive Engineering,
University of Ulsan,
Abstract A magneto-rheological (MR) fluid damper is
a semi-active control device that has
recently
begun to receive more attention in
the vibration
control community. However, the inherent
nonlinear nature of the MR fluid damper
makes
it challenging to use this device to
achieve
high damping control system performance.
The development of an accurate modeling
method
for a MR fluid damper is necessary
because
of its unique characteristics. Our
goal was
to develop an alternative method for
modeling
an MR fluid damper by using a self
tuning
fuzzy (STF) method based on neural
technique.
The behavior of the researched damper
is
directly estimated through a fuzzy
mapping
system. To improve the accuracy of
the STF
model, a back propagation and a gradient
descent method are used to train online
the
fuzzy parameters to minimize the model
error
function. A series of simulations were
done
to validate the effectiveness of the
suggested
modeling method when compared with
the data
measured from experiments on a test
rig with
a researched MR fluid damper. Finally,
modeling
results show that the proposed STF
interference
system trained online by using neural
technique
could describe well the behavior of
the MR
fluid damper without need of calculation
time for generating the model parameters.
Keyword: Magneto-rheological (MR) fluid-Damper-Modeling-Self
tuning-Fuzzy
_____________________________________________________________________________________________________________________________
Editor : International Affairs Committee
Published by The Japan Society of Mechanical
Engineers
Shinanomachi-Rengakan Bldg, Shinanomachi
35,
Shinjuku-ku, Tokyo 160-0016, Japan
FAX : 81-3-5360-3508
All Rights Reserved, Copyright C 2008
The Japan Society of Mechanical Engineers
URL:http//www.jsme.or.jp [English Version]
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