Mechanical
Mechanical
engineering
Mechanical engineering is an engineering discipline that
combines engineering physics and mathematics principles
with materials science to design, analyze, manufacture, and
maintain mechanical systems.
It is one of the oldest and broadest of the engineering
disciplines.
The mechanical engineering field requires
an understanding of core areas including mechanics, dynamics, thermodynamics, materials science, structural analysis,
and electricity. In addition to these core
principles, mechanical engineers use tools such as computer-aided design (CAD), computer-aided
manufacturing (CAM), and product lifecycle management to design
and analyze manufacturing plants, industrial equipment and machinery, heating
and cooling systems, transport systems, aircraft, watercraft, robotics, medical devices, weapons, and others. It is the branch of
engineering that involves the design, production, and operation of machinery.[1][2]
Mechanical engineering emerged as a field
during the Industrial Revolution in
Europe in the 18th century; however, its development can be traced back several
thousand years around the world. In the 19th century, developments in physics led to the development of
mechanical engineering science. The field has continually evolved to
incorporate advancements; today mechanical engineers are pursuing developments
in such areas as composites, mechatronics, and nanotechnology. It also overlaps with aerospace engineering, metallurgical
engineering, civil engineering, electrical
engineering, manufacturing
engineering, chemical engineering, industrial
engineering, and other engineering disciplines to varying amounts.
Mechanical engineers may also work in the field of biomedical
engineering, specifically with biomechanics, transport phenomena, biomechatronics, bionanotechnology, and modelling of biological
systems.
W16 engine of the Bugatti Veyron. Mechanical engineers
design engines, power plants, other machines...
..structures, and vehicles of all sizes.
Contents
·
1History
History
Main article: History
of mechanical engineering
The application of mechanical engineering
can be seen in the archives of various ancient and medieval societies. The six
classic simple machines were
known in the ancient Near East.
The wedge and
the inclined plane (ramp)
were known since prehistoric times.[3] The wheel,
along with the wheel and axle mechanism,
was invented in Mesopotamia (modern
Iraq) during the 5th millennium BC.[4] The lever mechanism
first appeared around 5,000 years ago in the Near East, where it was used in a
simple balance scale,[5] and to move large
objects in ancient
Egyptian technology.[6] The lever was also
used in the shadoof water-lifting device, the
first crane machine,
which appeared in Mesopotamia circa 3000 BC.[5] The earliest
evidence of pulleys date back to Mesopotamia in the
early 2nd millennium BC.[7]
The earliest practical water-powered machines, the water wheel and watermill, first appeared in the Persian Empire, in what are now Iraq and Iran,
by the early 4th century BC.[8] In ancient Greece, the works of Archimedes (287–212 BC) influenced mechanics
in the Western tradition. In Roman Egypt, Heron of Alexandria (c.
10–70 AD) created the first steam-powered device (Aeolipile).[9] In China, Zhang Heng (78–139 AD) improved a water clock and invented a seismometer, and Ma Jun (200–265 AD) invented a chariot
with differential gears.
The medieval Chinese horologist and engineer Su Song (1020–1101 AD) incorporated
an escapement mechanism into his astronomical clock tower two centuries before
escapement devices were found in medieval European clocks. He also invented the
world's first known endless power-transmitting chain drive.[10]
During the Islamic Golden Age (7th
to 15th century), Muslim
inventors made remarkable contributions in the field of
mechanical technology. Al-Jazari, who was one
of them, wrote his famous Book of Knowledge of Ingenious Mechanical
Devices in 1206 and presented many mechanical designs. Al-Jazari is
also the first known person to create devices such as the crankshaft and camshaft, which now form the basics of many
mechanisms.[11]
During the 17th century, important breakthroughs
in the foundations of mechanical engineering occurred in England. Sir Isaac Newton formulated Newton's Laws of
Motion and developed Calculus, the mathematical basis of physics.
Newton was reluctant to publish his works for years, but he was finally
persuaded to do so by his colleagues, such as Sir Edmond Halley, much to the benefit of all
mankind. Gottfried Wilhelm
Leibniz is also credited with creating Calculus during this
time period.[citation needed]
During the early 19th century industrial
revolution, machine tools were
developed in England, Germany, and Scotland. This allowed mechanical engineering
to develop as a separate field within engineering. They brought with them
manufacturing machines and the engines to power them.[12] The first British
professional society of mechanical engineers was formed in 1847 Institution
of Mechanical Engineers, thirty years after the civil engineers
formed the first such professional society Institution
of Civil Engineers.[13] On the European
continent, Johann von Zimmermann (1820–1901) founded the first factory for
grinding machines in Chemnitz, Germany in
1848.
In the United States, the American
Society of Mechanical Engineers (ASME) was formed in 1880,
becoming the third such professional engineering society, after the American
Society of Civil Engineers (1852) and the American
Institute of Mining Engineers (1871).[14] The first schools
in the United States to offer an engineering education were the United
States Military Academy in 1817, an institution now known
as Norwich University in
1819, and Rensselaer
Polytechnic Institute in 1825. Education in mechanical
engineering has historically been based on a strong foundation in mathematics
and science.[15]
Education
Archimedes' screw was
operated by hand and could efficiently raise water, as the animated red ball
demonstrates.
Degrees in mechanical engineering are
offered at various universities worldwide. Mechanical engineering programs
typically take four to five years of study and result in a Bachelor of
Engineering (B.Eng. or B.E.), Bachelor of Science (B.Sc.
or B.S.), Bachelor of Science Engineering (B.Sc.Eng.), Bachelor of
Technology (B.Tech.), Bachelor of Mechanical Engineering
(B.M.E.), or Bachelor of
Applied Science (B.A.Sc.) degree, in or with emphasis in
mechanical engineering. In Spain, Portugal and most of South America, where
neither B.S. nor B.Tech. programs have been adopted, the formal name for the
degree is "Mechanical Engineer", and the course work is based on five
or six years of training. In Italy the course work is based on five years of
education, and training, but in order to qualify as an Engineer one has to pass
a state exam at the end of the course. In Greece, the coursework is based on a
five-year curriculum and the requirement of a 'Diploma' Thesis, which upon
completion a 'Diploma' is awarded rather than a B.Sc.[citation needed]
In the United States, most undergraduate mechanical
engineering programs are accredited by
the Accreditation Board for Engineering and Technology (ABET)
to ensure similar course requirements and standards among universities. The
ABET web site lists 302 accredited mechanical engineering programs as of 11
March 2014.[16] Mechanical
engineering programs in Canada are accredited by the Canadian Engineering
Accreditation Board (CEAB),[17] and most other
countries offering engineering degrees have similar accreditation societies.
In Australia, mechanical engineering degrees are
awarded as Bachelor of Engineering (Mechanical) or similar nomenclature,
although there are an increasing number of specialisations. The degree takes
four years of full-time study to achieve. To ensure quality in engineering
degrees, Engineers Australia accredits
engineering degrees awarded by Australian universities in accordance with the
global Washington Accord.
Before the degree can be awarded, the student must complete at least 3 months
of on the job work experience in an engineering firm.[18] Similar systems are
also present in South Africa and are overseen by the Engineering Council of
South Africa (ECSA).
In India, to become an engineer, one needs
to have an engineering degree like a B.Tech or B.E, have a diploma in
engineering, or by completing a course in an engineering trade like fitter from
the Industrial
Training Institute (ITIs) to receive a "ITI Trade
Certificate" and also pass the All India Trade Test (AITT) with an
engineering trade conducted by the National Council of Vocational Training
(NCVT) by which one is awarded a "National Trade Certificate". A
similar system is used in Nepal.[citation needed]
Some mechanical engineers go on to pursue a
postgraduate degree such as a Master of Engineering, Master of Technology, Master of Science, Master of
Engineering Management (M.Eng.Mgt. or M.E.M.), a Doctor of Philosophy in
engineering (Eng.D. or Ph.D.) or an engineer's degree.
The master's and engineer's degrees may or may not include research. The Doctor of Philosophy includes a
significant research component and is often viewed as the entry point to academia.[19] The Engineer's
degree exists at a few institutions at an intermediate level between the
master's degree and the doctorate.
Coursework
Standards set by each country's
accreditation society are intended to provide uniformity in fundamental subject
material, promote competence among graduating engineers, and to maintain
confidence in the engineering profession as a whole. Engineering programs in
the U.S., for example, are required by ABET to show that their students can
"work professionally in both thermal and mechanical systems areas."[20] The specific courses
required to graduate, however, may differ from program to program. Universities
and Institutes of
technology will often combine multiple subjects into a single
class or split a subject into multiple classes, depending on the faculty
available and the university's major area(s) of research.
The fundamental subjects of mechanical
engineering usually include:
·
Mathematics (in particular, calculus, differential
equations, and linear algebra)
·
Basic physical sciences (including physics
and chemistry)
·
Thermodynamics, heat transfer, energy conversion, and HVAC
·
Fluid mechanics (including fluid statics and fluid dynamics)
·
Mechanism and Machine design
(including kinematics and dynamics)
·
Instrumentation and measurement
·
Manufacturing
engineering, technology, or processes
·
Hydraulics and Pneumatics
·
Mechatronics and robotics
Mechanical engineers are also expected to
understand and be able to apply basic concepts from chemistry, physics, Tribology, chemical engineering, civil engineering, and electrical
engineering. All mechanical engineering programs include multiple
semesters of mathematical classes including calculus, and advanced mathematical concepts
including differential
equations, partial
differential equations, linear algebra, abstract algebra, and differential geometry,
among others.
In addition to the core mechanical
engineering curriculum, many mechanical engineering programs offer more
specialized programs and classes, such as control systems, robotics, transport and logistics, cryogenics, fuel technology, automotive engineering, biomechanics, vibration, optics and others, if a separate
department does not exist for these subjects.[23]
Most mechanical engineering programs also
require varying amounts of research or community projects to gain practical
problem-solving experience. In the United States it is common for mechanical
engineering students to complete one or more internships while studying, though this
is not typically mandated by the university. Cooperative education is
another option. Future work skills[24] research puts
demand on study components that feed student's creativity and innovation.[25]
Job duties
Mechanical engineers research, design,
develop, build, and test mechanical and thermal devices, including tools,
engines, and machines.
Mechanical engineers typically do the
following:
·
Analyze problems to see how mechanical and
thermal devices might help solve the problem.
·
Design or redesign mechanical and thermal
devices using analysis and computer-aided design.
·
Develop and test prototypes of devices they
design.
·
Analyze the test results and change the
design as needed.
·
Oversee the manufacturing process for the
device.
Mechanical engineers design and oversee the
manufacturing of many products ranging from medical devices to new batteries.
They also design power-producing machines such as electric generators, internal
combustion engines, and steam and gas turbines as well as power-using machines,
such as refrigeration and air-conditioning systems.
Like other engineers, mechanical engineers
use computers to help create and analyze designs, run simulations and test how
a machine is likely to work.
License
and regulation
Engineers may seek license by a state, provincial, or
national government. The purpose of this process is to ensure that engineers
possess the necessary technical knowledge, real-world experience, and knowledge
of the local legal system to practice engineering at a professional level. Once
certified, the engineer is given the title of Professional Engineer (in
the United States, Canada, Japan, South Korea, Bangladesh and South
Africa), Chartered Engineer (in
the United Kingdom, Ireland, India and Zimbabwe), Chartered
Professional Engineer (in Australia and New Zealand) or European
Engineer (much of the European Union).
In the U.S., to become a licensed
Professional Engineer (PE), an engineer must pass the comprehensive FE
(Fundamentals of Engineering) exam, work a minimum of 4 years as an Engineering
Intern (EI) or Engineer-in-Training (EIT), and pass the
"Principles and Practice" or PE (Practicing Engineer or Professional
Engineer) exams. The requirements and steps of this process are set forth by
the National Council of Examiners for Engineering and
Surveying (NCEES), a composed of engineering and land surveying
licensing boards representing all U.S. states and territories.
In the UK, current graduates require
a BEng plus an appropriate master's degree
or an integrated MEng degree, a minimum of 4 years post
graduate on the job competency development and a peer reviewed project report
to become a Chartered Mechanical Engineer (CEng, MIMechE) through the Institution
of Mechanical Engineers. CEng MIMechE can also be obtained via an
examination route administered by the City
and Guilds of London Institute.[citation needed]
In most developed countries, certain
engineering tasks, such as the design of bridges, electric power plants, and
chemical plants, must be approved by a professional engineer or
a chartered engineer.
"Only a licensed engineer, for instance, may prepare, sign, seal and
submit engineering plans and drawings to a public authority for approval, or to
seal engineering work for public and private clients."[26] This requirement
can be written into state and provincial legislation, such as in the Canadian
provinces, for example the Ontario or Quebec's Engineer Act.[27]
In other countries, such as Australia, and
the UK, no such legislation exists; however, practically all certifying bodies
maintain a code of ethics independent
of legislation, that they expect all members to abide by or risk expulsion.[28]
Further
information: FE Exam, Professional Engineer, Incorporated Engineer, Washington Accord, and Regulation
and licensure in engineering
Salaries
and workforce statistics
The total number of engineers employed in
the U.S. in 2015 was roughly 1.6 million. Of these, 278,340 were mechanical
engineers (17.28%), the largest discipline by size.[29] In 2012, the median
annual income of mechanical engineers in the U.S. workforce was $80,580. The
median income was highest when working for the government ($92,030), and lowest
in education ($57,090).[30] In 2014, the total
number of mechanical engineering jobs was projected to grow 5% over the next
decade.[31] As of 2009, the
average starting salary was $58,800 with a bachelor's degree.[32]
Subdisciplines
The field of mechanical engineering can be
thought of as a collection of many mechanical engineering science disciplines.
Several of these subdisciplines which are typically taught at the undergraduate
level are listed below, with a brief explanation and the most common
application of each. Some of these subdisciplines are unique to mechanical
engineering, while others are a combination of mechanical engineering and one
or more other disciplines. Most work that a mechanical engineer does uses
skills and techniques from several of these subdisciplines, as well as
specialized subdisciplines. Specialized subdisciplines, as used in this
article, are more likely to be the subject of graduate studies or on-the-job
training than undergraduate research. Several specialized subdisciplines are
discussed in this section.
Mohr's circle, a common tool to study stresses in a mechanical
element
Main article: Mechanics
Mechanics is, in the most general sense,
the study of forces and their effect upon matter. Typically, engineering mechanics is
used to analyze and predict the acceleration and deformation (both elastic and plastic) of
objects under known forces (also called loads) or stresses. Subdisciplines of mechanics include
·
Statics, the study of non-moving bodies under
known loads, how forces affect static bodies
·
Dynamics the
study of how forces affect moving bodies. Dynamics includes kinematics (about
movement, velocity, and acceleration) and kinetics (about forces and resulting
accelerations).
·
Mechanics of
materials, the study of how different materials deform under various
types of stress
·
Kinematics, the study of the motion of bodies
(objects) and systems (groups of objects), while ignoring the forces that cause
the motion. Kinematics is often used in the design and analysis of mechanisms.
·
Continuum mechanics,
a method of applying mechanics that assumes that objects are continuous (rather
than discrete)
Mechanical engineers typically use
mechanics in the design or analysis phases of engineering. If the engineering
project were the design of a vehicle, statics might be employed to design the
frame of the vehicle, in order to evaluate where the stresses will be most
intense. Dynamics might be used when designing the car's engine, to evaluate
the forces in the pistons and cams as
the engine cycles. Mechanics of materials might be used to choose appropriate
materials for the frame and engine. Fluid mechanics might be used to design a
ventilation system for the vehicle (see HVAC),
or to design the intake system for the
engine.
Mechatronics
and robotics
Training FMS with
learning robot SCORBOT-ER 4u, workbench
CNC Mill and CNC Lathe
Main articles: Mechatronics and Robotics
Mechatronics is a combination of mechanics
and electronics. It is an interdisciplinary branch of mechanical
engineering, electrical
engineering and software engineering that
is concerned with integrating electrical and mechanical engineering to create
hybrid systems. In this way, machines can be automated through the use of electric motors, servo-mechanisms, and other electrical systems
in conjunction with special software. A common example of a mechatronics system
is a CD-ROM drive. Mechanical systems open and close the drive, spin the CD and
move the laser, while an optical system reads the data on the CD and converts
it to bits. Integrated software controls the process
and communicates the contents of the CD to the computer.
Robotics is the application of mechatronics
to create robots, which are often used in industry to perform tasks that are
dangerous, unpleasant, or repetitive. These robots may be of any shape and
size, but all are preprogrammed and interact physically with the world. To
create a robot, an engineer typically employs kinematics (to determine the
robot's range of motion) and mechanics (to determine the stresses within the
robot).
Robots are used extensively in industrial
engineering. They allow businesses to save money on labor, perform
tasks that are either too dangerous or too precise for humans to perform them
economically, and to ensure better quality. Many companies employ assembly lines of robots, especially in
Automotive Industries and some factories are so robotized that they can
run by themselves.
Outside the factory, robots have been employed in bomb disposal, space exploration, and many other fields.
Robots are also sold for various residential applications, from recreation to
domestic applications.
Structural
analysis
Main articles: Structural analysis and Failure analysis
Structural analysis is the branch of
mechanical engineering (and also civil engineering) devoted to examining why
and how objects fail and to fix the objects and their performance. Structural
failures occur in two general modes: static failure, and fatigue failure. Static
structural failure occurs when, upon being loaded (having a force
applied) the object being analyzed either breaks or is deformed plastically,
depending on the criterion for failure. Fatigue failure occurs
when an object fails after a number of repeated loading and unloading cycles.
Fatigue failure occurs because of imperfections in the object: a microscopic
crack on the surface of the object, for instance, will grow slightly with each
cycle (propagation) until the crack is large enough to cause ultimate failure.[34]
Failure is not simply defined as when a
part breaks, however; it is defined as when a part does not operate as
intended. Some systems, such as the perforated top sections of some plastic
bags, are designed to break. If these systems do not break, failure analysis
might be employed to determine the cause.
Structural analysis is often used by
mechanical engineers after a failure has occurred, or when designing to prevent
failure. Engineers often use online documents and books such as those published
by ASM[35] to aid them in
determining the type of failure and possible causes.
Once theory is applied to a mechanical
design, physical testing is often performed to verify calculated results. Structural
analysis may be used in an office when designing parts, in the field to analyze
failed parts, or in laboratories where parts might undergo controlled failure
tests.
Thermodynamics
and thermo-science
Main article: Thermodynamics
Thermodynamics is an applied science used
in several branches of engineering, including mechanical and chemical
engineering. At its simplest, thermodynamics is the study of energy, its use
and transformation through a system.[36] Typically,
engineering thermodynamics is concerned with changing energy from one form to
another. As an example, automotive engines convert chemical energy (enthalpy) from the fuel into heat, and then
into mechanical work that eventually turns the wheels.
Thermodynamics principles are used by
mechanical engineers in the fields of heat transfer, thermofluids, and energy conversion. Mechanical engineers use
thermo-science to design engines and power plants, heating, ventilation, and
air-conditioning (HVAC) systems, heat exchangers, heat sinks, radiators, refrigeration, insulation,
and others.[37]
Design
and drafting
A CAD model of a mechanical double seal
Main articles: Technical drawing and CNC
Drafting or technical drawing is the
means by which mechanical engineers design products and create instructions
for manufacturing parts. A technical drawing
can be a computer model or hand-drawn schematic showing all the dimensions
necessary to manufacture a part, as well as assembly notes, a list of required
materials, and other pertinent information.[38] A U.S. mechanical
engineer or skilled worker who creates technical drawings may be referred to as
a drafter or draftsman. Drafting has historically been a two-dimensional
process, but computer-aided design (CAD)
programs now allow the designer to create in three dimensions.
Instructions for manufacturing a part must
be fed to the necessary machinery, either manually, through programmed
instructions, or through the use of a computer-aided
manufacturing (CAM) or combined CAD/CAM program. Optionally, an
engineer may also manually manufacture a part using the technical drawings.
However, with the advent of computer numerically
controlled (CNC) manufacturing, parts can now be fabricated
without the need for constant technician input. Manually manufactured parts
generally consist of spray coatings,
surface finishes, and other processes that cannot economically or practically
be done by a machine.
Drafting is used in nearly every
subdiscipline of mechanical engineering, and by many other branches of
engineering and architecture. Three-dimensional models created using CAD
software are also commonly used in finite element
analysis (FEA) and computational
fluid dynamics (CFD).
Modern tools
An oblique view of a
four-cylinder inline crankshaft with pistons
Many mechanical engineering companies,
especially those in industrialized nations, have begun to incorporate computer-aided
engineering (CAE) programs into their existing design and
analysis processes, including 2D and 3D solid modeling computer-aided design (CAD).
This method has many benefits, including easier and more exhaustive
visualization of products, the ability to create virtual assemblies of parts,
and the ease of use in designing mating interfaces and tolerances.
Other CAE programs commonly used by
mechanical engineers include product
lifecycle management (PLM) tools and analysis tools used to
perform complex simulations. Analysis tools may be used to predict product
response to expected loads, including fatigue life and manufacturability. These
tools include finite element
analysis (FEA), computational
fluid dynamics (CFD), and computer-aided
manufacturing (CAM).
Using CAE programs, a mechanical design
team can quickly and cheaply iterate the design process to develop a product
that better meets cost, performance, and other constraints. No physical
prototype need be created until the design nears completion, allowing hundreds
or thousands of designs to be evaluated, instead of a relative few. In
addition, CAE analysis programs can model complicated physical phenomena which
cannot be solved by hand, such as viscoelasticity, complex contact between
mating parts, or non-Newtonian flows.
As mechanical engineering begins to merge
with other disciplines, as seen in mechatronics, multidisciplinary
design optimization (MDO) is being used with other CAE programs
to automate and improve the iterative design process. MDO tools wrap around
existing CAE processes, allowing product evaluation to continue even after the
analyst goes home for the day. They also utilize sophisticated optimization
algorithms to more intelligently explore possible designs, often finding
better, innovative solutions to difficult multidisciplinary design problems.
Areas of research
Mechanical engineers are constantly pushing
the boundaries of what is physically possible in order to produce safer,
cheaper, and more efficient machines and mechanical systems. Some technologies
at the cutting edge of mechanical engineering are listed below (see also exploratory
engineering).
Micro
electro-mechanical systems (MEMS)
Micron-scale mechanical components such as
springs, gears, fluidic and heat transfer devices are fabricated from a variety
of substrate materials such as silicon, glass and polymers like SU8.
Examples of MEMS components are the accelerometers
that are used as car airbag sensors, modern cell phones, gyroscopes for precise
positioning and microfluidic devices used in biomedical applications.
Friction
stir welding (FSW)
Main article: Friction stir welding
Friction stir welding, a new type of welding, was discovered in 1991 by The Welding Institute (TWI).
The innovative steady state (non-fusion) welding technique joins materials
previously un-weldable, including several aluminum alloys.
It plays an important role in the future construction of airplanes, potentially
replacing rivets. Current uses of this technology to date include welding the
seams of the aluminum main Space Shuttle external tank, Orion Crew Vehicle,
Boeing Delta II and Delta IV Expendable Launch Vehicles and the SpaceX Falcon 1
rocket, armor plating for amphibious assault ships, and welding the wings and
fuselage panels of the new Eclipse 500 aircraft from Eclipse Aviation among an
increasingly growing pool of uses.[39][40][41]
Composites
Composite cloth
consisting of woven carbon fiber
Main article: Composite material
Composites or composite materials are a
combination of materials which provide different physical characteristics than
either material separately. Composite material research within mechanical
engineering typically focuses on designing (and, subsequently, finding
applications for) stronger or more rigid materials while attempting to
reduce weight, susceptibility to corrosion, and other
undesirable factors. Carbon fiber reinforced composites, for instance, have
been used in such diverse applications as spacecraft and fishing rods.
Mechatronics
Mechatronics is the synergistic
combination of mechanical engineering, electronic
engineering, and software engineering. The discipline of
mechatronics began as a way to combine mechanical principles with electrical
engineering. Mechatronic concepts are used in the majority of
electro-mechanical systems.[42] Typical
electro-mechanical sensors used in mechatronics are strain gauges,
thermocouples, and pressure transducers.
Nanotechnology
Main article: Nanotechnology
At the smallest scales, mechanical
engineering becomes nanotechnology—one speculative goal of which is to create
a molecular assembler to
build molecules and materials via mechanosynthesis. For now that goal remains
within exploratory engineering.
Areas of current mechanical engineering research in nanotechnology include
nanofilters,[43] nanofilms,[44] and nanostructures,[45] among others.
See also: Picotechnology
Finite
element analysis
Main article: Finite element
analysis
Finite Element Analysis is a computational
tool used to estimate stress, strain, and deflection of solid bodies. It uses a
mesh setup with user-defined sizes to measure physical quantities at a node.
The more nodes there are, the higher the precision.[46] This field is not
new, as the basis of Finite Element Analysis (FEA) or Finite Element Method
(FEM) dates back to 1941. But the evolution of computers has made FEA/FEM a
viable option for analysis of structural problems. Many commercial codes such
as NASTRAN, ANSYS,
and ABAQUS are widely used in industry for
research and the design of components. Some 3D modeling and CAD software
packages have added FEA modules. In the recent times, cloud simulation
platforms like SimScale are
becoming more common.
Other techniques such as finite difference
method (FDM) and finite-volume method (FVM) are employed to solve problems
relating heat and mass transfer, fluid flows, fluid surface interaction, etc.
Biomechanics
Main article: Biomechanics
Biomechanics is the application of
mechanical principles to biological systems, such as humans, animals, plants, organs, and cells.[47] Biomechanics also
aids in creating prosthetic limbs and artificial organs for humans. Biomechanics
is closely related to engineering, because
it often uses traditional engineering sciences to analyze biological systems.
Some simple applications of Newtonian mechanics and/or materials sciences can supply correct
approximations to the mechanics of many biological systems.
In the past decade, reverse engineering of
materials found in nature such as bone matter has gained funding in academia.
The structure of bone matter is optimized for its purpose of bearing a large
amount of compressive stress per unit weight. [48] The goal is to
replace crude steel with bio-material for structural design.
Over the past decade the Finite element method (FEM)
has also entered the Biomedical sector highlighting further engineering aspects
of Biomechanics. FEM has since then established itself as an alternative
to in vivo surgical assessment and gained
the wide acceptance of academia. The main advantage of Computational
Biomechanics lies in its ability to determine the endo-anatomical response of
an anatomy, without being subject to ethical restrictions.[49] This has led FE
modelling to the point of becoming ubiquitous in several fields of Biomechanics
while several projects have even adopted an open source philosophy (e.g.
BioSpine).
Computational
fluid dynamics
Main article: Computational
fluid dynamics
Computational fluid dynamics, usually
abbreviated as CFD, is a branch of fluid mechanics that uses numerical methods
and algorithms to solve and analyze problems that involve fluid flows.
Computers are used to perform the calculations required to simulate the
interaction of liquids and gases with surfaces defined by boundary conditions.[50] With high-speed
supercomputers, better solutions can be achieved. Ongoing research yields
software that improves the accuracy and speed of complex simulation scenarios
such as turbulent flows. Initial validation of such software is performed using
a wind tunnel with the final validation coming in full-scale testing, e.g.
flight tests.
Acoustical
engineering
Main article: Acoustical
engineering
Acoustical engineering is one of many other
sub-disciplines of mechanical engineering and is the application of acoustics.
Acoustical engineering is the study of Sound and Vibration. These engineers work effectively to
reduce noise pollution in
mechanical devices and in buildings by soundproofing or removing sources of
unwanted noise. The study of acoustics can range from designing a more
efficient hearing aid, microphone, headphone, or recording studio to enhancing
the sound quality of an orchestra hall. Acoustical engineering also deals with
the vibration of different mechanical systems.[51]
Related fields
Manufacturing
engineering, aerospace engineering and automotive
engineering are grouped with mechanical engineering at times. A
bachelor's degree in these areas will typically have a difference of a few
specialized classes.
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