| ====================================================================== ENGINEERING NEWS IN BRIEF E-Mail Newsletter No.83 Issued by the Asian TOP Panel, November 2008 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) ====================================================================== 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 2008. ====================================================================== [Contents] 1) Development of Combined Heat and Power System applied Distributed Heat Storage Units in Multifamily Building (Source: JSME) 2) Condition Monitoring of Railway Track Using In-Service Vehicle (Source: JSME) 3) Risk-Based-Approach of Machinery Safety (Source: JSME) 4) Goldfire Innovator: The Solution to Support all People who are Involved in Manufacturing Business (Source: JSME) 5) Development of Micro Gear Reducer (Source: JSME) 6) Design Method of Magnetorheological Fluid Shock Absorber for Car Suspension (Source: CMES) 7) Simplified Scaling Transformation for the Numerical Simulation of MEMS Devices with Thin Film Structures (Source: CMES) 8) Approach for Maintenance Strategy Decision Making with Mixed Data (Source: CMES) 9) Hybrid Welding Process for Sheet Metal and Narrow Gap Fill Pass (Source: KSME) 10)Numerical Study of Pulsatile Blood Flow in Stenotic Artery (Source: KSME) 11)High Power Laser Driven Shock Compression of Metals and Its Innovative Applications (Source: KSME) ======================================================================== 1)Development of Combined Heat and Power System applied Distributed Heat Storage Units in Multifamily Building Yoshinori HISAZUMI, Osaka Gas Co.,LTD ======================================================================== 2) Condition Monitoring of Railway Track Using In-Service Vehicle Hitoshi TSUNASHIMA, Nihon University The development of a portable condition monitoring
system for railway track which is easily
set on in-service vehicle is summarized.
In this system, irregularities of rail are
estimated from vertical and lateral acceleration
of car body. A roll angle of car body, which
is calculated using a rate gyroscope, is
used to distinguish irregularity of line
from irregularity of level. Rail corrugation
can be detected from cabin noise with spectral
peek calculation. GPS system and map matching
algorithm localizes the fault on track. A
field test was conducted using a commercial
line in cooperation with a railway operating
company. Track irregularity was detected
by vertical and lateral acceleration measured
while the vehicle was running, and corrugation
was detected by spectral peaks of cabin noise.
Track condition was displayed on a route
map in real time together with information
of the location based on the position information
obtained by GPS. The field results show that
the condition monitoring of railway track
using in-service vehicle is possible with
the developed probe system. Takashi KABE, NPO Safety Engineering Laboratory The development of science and technology
brings on one hand welfare to the society,
but on the other hand danger to human
being.
The products are human-made and designers
of machinery have therefore the responsibility
to control hazards according to Risk-Based-Approach
(RBA) to prevent accidents beforehand.
The
Japanese domestic legislation and standards
have implemented the framework of global
approach on safety of machinery in
these
days. This framework consists out of
labor
safety law and Japanese industrial
standard
(JIS), which is adapted to international
standards, ISO or IEC on safety of
machinery.
In case of Japan, the relevant law
requires
the responsibility of user of machinery
only
and not yet of the machinery manufacturer.
Thus users of machinery are required
to pay
attention, that purchasing machines
are safe
and fulfill also requirements of products
liability law or contract law. The
methodology
risk assessment has a major role in
this
prevention way. Koumei NAGASHIMA, Cybernet Systems Co., Ltd In this article, the functionalities and
the advantages of Goldfire Innovator,
a novel
and unique software developed by Invention
Machine Corporation (IMC), and a specific
example of a user case is introduced.
The
concept of Goldfire Innovator is to
'accelerate
innovation', and according to IMC乫s theory, it can be accomplished by
making the product development process
more
efficient and by utilizing the results
repeatedly.
Goldfire Innovator makes it possible
to cope
with the deficiencies of existing products
or designs, review the functional designs,
and do risk analysis. In order to deliver
the advantages above, Goldfire Innovator
implements the problem solving methodologies
and knowledge management framework
integrated.
The frameworks include; TRIZ for inventive
problem solving, FMEA for risk analysis,
function models and value engineering
for
studying devices and processes, root
cause
analysis to identify root causes of
failures
or accidents, patent analysis, and
the semantic
analyzing technologies to control worldwide
engineering documents. One of the best
practices
of problem solving procedure with above
functions
is explained. As a user case, you can
find
how an oil company successfully reached
the
new bio-energy material using Goldfire
Innovator. Hideo KATORI, Tecpha Japan Inc., The necessity of a minute mechanism and the
device can enumerate the field of the
medical
treatment machine in the beginning.
That
is, to suppress the damage of the body
to
the minimum, an endoscope as small
as possible,
a tool of a celiac [**] operation,
and a
micro pump, etc. are demanded. Then,
the
micro gear reducer (1.5mm in the outside diameter and about
4mm in length) by the planetary gear
mechanism
that was able to be applied to the
field
of the medical treatment machine was
developed. Liao Changrong, Zhang Honghui, Yu Miao, Chen
Weimin The Bingham constitutive model, which is
previously used in depiction of magnetorheological
(MR) fluids rheological behaviors for
design
devices, exhibits discontinuous characteristics
in representation of pre-yield behaviors
and post-yield behaviors. A Biviscous
constitutive
model is presented to depict rheological
behaviors of MR fluids and design automotive
shock absorber. Quasi-static flow equations
of MR fluids in annular channels are
set
theoretically up based on Navier-Stokes
equations
and several rational simplifications
are
made. And both flow boundary conditions
and
flow compatibilities conditions are
established.
Meantime, analytical velocity profiles
of
MR fluids though annular channels are
obtained
via solution of the quasi-static flow
equations
using Biviscous constitutive model.
The predition
methodology of damping force offered
by MR
fluid shock absorber is formulated
and damping
performances are predicated in order
to determine
design parameters. MR fluid shock absorber
for Mazda 323 car suspension is designed
and fabricated in Chongqing University,
China.
Measurements from sinusoidal displacement
cycle by Shanchuan Shock Absorber Ltd.
of
China North Industry Corporation reveal
that
the anyalytical methodology and design
theory
are reasonable. Wang Wei, Li Zhihong Thin film is a widely used structure in the
present microelectromechanical systems
(MEMS)
and plays a vital role in many functional
devices. However, the great size difference
between the film乫s thickness and its
planar
dimensions makes it difficult to study
the
thin film performance numerically.
In this
work, a scaling transformation was
presented
to make the different dimensional sizes
equivalent,
and thereby, to improve the grid quality
considerably. Two numerical experiments
were
studied to validate the present scaling
transformation
method. The numerical results indicated
that
the largest grid size difference can
be decreased
to one to two orders of magnitude by
using
the present scaling transformation,
and the
memory required by the numerical simulation,
i.e., the total grid number, could
be reduced
by about two to three orders of magnitude,
while the numerical accuracies with
and without
this scaling transformation were nearly
the
same. Li Changyou, Xu Minqiang, Guo Song, Wang
Rixin, Huang Wenhu Studying on the problem of maintenance strategy decision making of equipment can reduce the maintenance cost and improve the availability, reliability, safety of a machine, and product quality. Although it has had a certain extent of development, the problem of maintenance strategy decision making with mixed data has never been resolved. The local concordance index and discordance index is defined based on the stochastic dominance to compare one maintenance strategy with others under stochastic evaluation; the fuzzy evaluations are transformed to the corresponding fuzzy numbers, then, the local concordance index and discordance index are defined based on the distance index between the centroid point of a fuzzy number and original point to resolve the problem of maintenance strategy decision making under fuzzy evaluation. Based on the above processing, the fuzzy and stochastic evaluations are treated the same the deterministic in ELECTRE III in order to solve the problem of maintenance strategy decision making with mixed data. The proposed approach is applied to selecting the most appropriate maintenance strategy for the steam turbine of steam-power plant. The result shows that the approach is sound and effective. Key words: Maintenance strategy, Mixed data, Multiple
attribute decision making, Stochastic dominance,
Ranking fuzzy numbers, ELECTRE III, Steam
turbine Hae Woon Choi, Hyun Myung Shin, Moon Hyuk
Im An application of innovative laser+GMA hybrid welding process is presented for reducing bead humping defects in high speed welding and increasing side wall fusion in narrow groove welding without torch or wire oscillation. In this hybrid process, the laser heat input is applied adjacent to the weld pool at a relatively low power density to produce a wider, flatter weld bead. In bead on plate in sheet metal gauges, the hybrid process was able to produce hump-free welds from 70ipm (~1780噊/min) to over 150ipm (~3810噊/min) of the travel speed compared to the un-assisted GMAW process. A square-butt joint in 15mm A572 Gr50 steel welds was investigated. A square butt joint with a gap of 3.2噊 was filled with 6 passes. Liquid Nitrogen calorimetry and innovative CO? laser reflective optics were also developed to demonstrate the concept of hybrid welding. Key words: Hybrid Welding, Sheet Metal, Narrow Gap Taewon Seo, Bahtiyor Buriev Key words: Pulsatile Flow, Stenotic Artery, Wall Shear Stress, Recirculation, Reattachment
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