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A Reusable Launch Vehicle (RLV) Akash Bhosale and Abrarahmad Mulla Launching satellites or humans to space is a costly affair. Since man stepped on moon, it has been the constant dream of engineers, policymakers and others among the space community to develop and design a vehicle that can be used for multiple launch missions, like an aircraft, whether military or transport. The only success achieved so far is the Space Shuttle Program that has been shelved in 2011. The retirement of the Space Shuttle has left a huge void in the field of space exploration, and even though NASA is following up with the space capsule Orion, there is a renewed interest in Reusable Launch Vehicles (RLV). The Indian Space Research Organization (ISRO) announced on January 7 th , 2015, that they will perform a RLV technology demonstration in March. If successful, this test will be a big achievement for India and ISRO, and will cement its position as a forerunner in the field of space exploration. What is a Reusable Launch Vehicle? A Reusable Launch Vehicle (RLV) is the space analog of an aircraft. Ideally it takes off vertically on the back of an expendable rocket and then glides back down like an aircraft. During landing phase, an RLV can either land on a runway or perform a splashdown. Small wings provide maneuverability support during landing.The main advantage of an RLV is it can be used multiple times, hopefully with low servicing costs. The expendable rocket that is used for launching the RLV can also be designed to be used multiple times. A successful RLV would surely cut down mission costs and make space travel more accessible. Vehicle Technology Demonstrator (RLV-TD) to act as a platform to demonstrate various technologies like 1) Hypersonic flight, 2) Autonomous landing, 3) Flush air data measurements, 4) Re-entry thermal protection systems, etc. Indian Perspective on RLV: ISRO’s RLV Technology Demonstration Programme (RLV-TD) is a plane-like reusable vehicle launched by an expendable single state solid booster. The mission will end with a splashdown in the Indian Ocean.The rocket launcher will help it to reach Mach 6, and an altitude of 100 km. After reaching the required height it will undergo the re-entry phase, glide down and finally splash down in the Bay of Bengal. The vehicle will spend

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A Reusable Launch Vehicle (RLV)

Akash Bhosale and Abrarahmad Mulla

Launching satellites or humans to space is a costly affair. Since man stepped on moon, it has been the constant

dream of engineers, policymakers and others among the space community to develop and design a vehicle that

can be used for multiple launch missions, like an aircraft, whether military or transport. The only success

achieved so far is the Space Shuttle Program that has been shelved in 2011. The retirement of the Space Shuttle

has left a huge void in the field of space exploration, and even though NASA is following up with the space

capsule Orion, there is a renewed interest in Reusable Launch Vehicles (RLV).

The Indian Space Research Organization (ISRO) announced on January 7th

, 2015, that they will perform a RLV

technology demonstration in March. If successful, this test will be a big achievement for India and ISRO, and

will cement its position as a forerunner in the field of space exploration.

What is a Reusable Launch Vehicle?

A Reusable Launch Vehicle (RLV) is the space analog of an aircraft. Ideally it takes off vertically on the back

of an expendable rocket and then glides back down like an aircraft. During landing phase, an RLV can either

land on a runway or perform a splashdown. Small wings provide maneuverability support during landing.The

main advantage of an RLV is it can be used multiple times, hopefully with low servicing costs. The expendable

rocket that is used for launching the RLV can also be designed to be used multiple times. A successful RLV

would surely cut down mission costs and make space travel more accessible.

Vehicle Technology Demonstrator (RLV-TD) to act as a platform to demonstrate various

technologies like

1) Hypersonic flight,

2) Autonomous landing,

3) Flush air data measurements,

4) Re-entry thermal protection systems, etc.

Indian Perspective on RLV:

ISRO’s RLV Technology Demonstration Programme (RLV-TD) is a plane-like reusable vehicle launched by an

expendable single state solid booster. The mission will end with a splashdown in the Indian Ocean.The rocket

launcher will help it to reach Mach 6, and an altitude of 100 km. After reaching the required height it will

undergo the re-entry phase, glide down and finally splash down in the Bay of Bengal. The vehicle will spend

nearly 5 minutes in its coast phase at the maximum altitude before doing re-entry.The RLV-TD Program is not

just a technology demonstration for India, but a way to prove how much it has progressed in the field of space

exploration. The test is a part of a larger plan to build a fully functional two stage to orbit (TSTO) vehicle.

Currently the annual spending budget of IRO for launching satellites is Rs. 300 cr (48.7M USD). A successful

RLV program would reduce the cost of space missions, making India more competitive in the launcher market.

For now, the test program will expand the technological capabilities of India, enabling it to be a forerunner in

space exploration in near future.The success of the Mars Orbiter Mission at the first attempt has boosted the

hopes of ISRO to send humans to Mars. A highly developed version of RLV for launching humans to

space could demonstrate the technological ability and progress achieved by Indians in the field of space

exploration. The series of experiments that need to be carried out will help in expansion of space technology

and capability of ISRO and India culminating in a fully developed version of RLV used as Two Stages to Orbit

(TSTO) vehicle.

1 BLADELESS FAN AMEY SAPKAL(BE MECH)

In October 2009, James Dyson's consumer electronics company, famous for its

line of vacuum cleaners, introduced a new device to the market called the Dyson

Air Multiplier. The Air Multiplier is a fan with an unusual characteristic: It doesn't

have any visible blades. It appears to be a circular tube mounted on a pedestal. The

shallow tube is only a few inches deep.

Looking at the device, you wouldn't expect to feel a breeze coming from the

mounted circle. There are no moving parts in sight. But if the fan is switched on,

you'll feel air blowing through the tube. How does it work? How can an open circle

push air into a breeze without fan blades?

As you might imagine, there are a few scientific principles at play here. There's

also an electronic element. While the tube doesn't have any blades inside it, the

2 BLADELESS FAN AMEY SAPKAL(BE MECH)

pedestal of the fan contains a brushless electric motor that takes in air and feeds it

into the circular tube. Air flows along the inside of the device until it reaches a slit

inside the tube. This provides the basic airflow that creates the breeze you'd feel if

you stood in front of the fan.

According to Dyson, the breeze generated by the Air Multiplier is more consistent

and steady than one from a standard fan with blades. Since there are no rotating

blades, the breeze from the fan doesn't buffet you with short gusts of air.

How the Dyson Bladeless Fan Works??????

Calling the Dyson Air Multiplier a fan with no blades is perhaps a touch

misleading. There are blades in the fan -- you just can't see them because they're

hidden in the pedestal. A motor rotates nine asymmetrically aligned blades to

pull air into the device. According to Dyson, these blades can pull in up to 5.28

gallons (about 20 liters) of air per second.

The air flows through a channel in the pedestal up to the tube, which is hollow.

The interior of the tube acts like a ramp. Air flows along the ramp, which curves

around and ends in slits in the back of the fan. Then, the air flows along the surface

of the inside of the tube and out toward the front of the fan. But how does the fan

multiply the amount of air coming into the pedestal of the device?

3 BLADELESS FAN AMEY SAPKAL(BE MECH)

It boils down to physics. While it's true that the atmosphere is gaseous, gases obey

the physical laws of fluid dynamics. As air flows through the slits in the tube and

out through the front of the fan, air behind the fan is drawn through the tube as

well. This is called inducement. The flowing air pushed by the motor induces the

air behind the fan to follow.

Air surrounding the edges of the fan will also begin to flow in the direction of the

breeze. This process is called entrainment. Through inducement and entrainment,

Dyson claims the Air Multiplier increases the output of airflow by 15 times the

amount it takes in through the pedestal's motor.

James Dyson demonstrates that there are indeed no visible blades on the Air Multiplier.

CLOUD MANUFACTURING

UJWAL D. ADMUTHE (T.E, A)

AKASH V. BHOSALE (T.E, A) Page 1

CLOUD MANUFACTURING

DEFINITION

Cloud manufacturing is a service-oriented, knowledge-based smart

manufacturing system with high efficiency and low energy consumption. In a

cloud manufacturing system, state-of-the-art technologies such as informatized

manufacturing technology, cloud computing, Internet of Things, semantic Web,

high-performance computing, and cloud manufacturing are integrated. By

extending and shifting existing manufacturing and service systems,

manufacturing resources and capabilities are virtualized and oriented towards

service provision. Cloud manufacturing provides the whole manufacturing

lifecycle with secure, reliable, high quality, and on-demand services at low

prices through networked system. The manufacturing lifecycle includes pre-

manufacturing (argumentation, design, production and sale), manufacturing

(product usage, management and maintenance), and post-manufacturing

(dismantling, scrap, and recycling).

So What Exactly is the Cloud?

“cloud” simply means that your software, data and related infrastructure are

hosted remotely via the Internet. Cloud manufacturing has become so popular

because it lowers costs while scaling seamlessly with your business. Essentially

you’re paying someone else to deal with your IT headaches, including support,

security and maintenance. You only pay for what you need, and you can expand

or change cloud services on the fly — with no capital outlay.

Operation Model and Key Technologies of Cloud Manufacturing A cloud manufacturing system consists of manufacturing resources and

capabilities, manufacturing cloud, and the whole manufacturing lifecycle

applications. It also includes core support (knowledge), two processes (import

and export), and three user types—resource providers, cloud operators and

resource users. Figure 1 illustrates the operational principle of cloud

manufacturing. Manufacturing resources and capabilities are encapsulated as

cloud services. This process is called manufacturing resource "import".

Depending on different manufacturing requirements, cloud services are

combined to form a manufacturing cloud. The cloud provides the whole

manufacturing lifecycle applications with diverse services. This process is

called "export". Knowledge plays a central role in supporting the entire

operating process of cloud manufacturing. It is necessary for intelligent

embedding and virtualized encapsulation during import; it assists functions such

as intelligent search of cloud services; and it facilitates smart cooperation of

cloud services over the whole manufacturing lifecycle. In cloudmanufacturing

system, knowledge-based integration across the whole lifecycle is possible.

CLOUD MANUFACTURING

UJWAL D. ADMUTHE (T.E, A)

AKASH V. BHOSALE (T.E, A) Page 2

A cloud manufacturing application Users send specific requests to the cloud manufacturing platform. This platform

is responsible for the management, operation, and maintenance of

manufacturing clouds and service tasks such as import and export. It analyzes

and divides service requests, and automatically searches the cloud for best-

matched services. By a series of processes including scheduling, optimization

and combination, a solution is generated and then sent back to the client. A user

does not need to communicate directly with every service node, nor find the

specific locations and situations of service nodes. Through the cloud

manufacturing platform, manufacturing resources and capabilities can be used

in the same way as water, gas, electricity, etc.

References

• https://en.wikipedia.org/wiki/Cloud_manufacturing

• https://commons.wikimedia.org

• ftp://ftp.nist.gov/pub/mel/michalos/Publications/2014/JournalPaper/bib/C

loud-Based%20manufacturing%20systems.pdf

NileshsingRajput(Department Of Mechanical Engineering) Page 1

Casting directly from a computer model by

using advanced simulation software

FLOW-3D Cast

INTRODUCTION:

In todays highly competitive world saving in product development cost is very important. For

that purpose new methods to be adopted for manufacturing as well as simulation and

optimization of processes. A patternless casting technique, originally conceived at VTT

Technical Research Centre of Finland andfurther developed at its spin-off company, Simtech

Systems, offers up to 40% savings in product development costs, and upto two months shorter

development times compared to conventional techniques. Savings of this order can be very

valuable on today's highly competitive markets. Casting simulation is commonly used for

designing of casting systems. However, most of the software are today old fashioned and

predicting just shrinkage porosity. Flow Science, VTT and Simtech have developed new

software called FLOW-3D Cast , which can simulate surface defects, air entrainment, filters, core

gas problems and even a cavitation.

Simtech’spatternless casting technology allows developers to completely by-pass one of the

main stages in traditional casting the making of casting patterns. The advantages of this approach

are best appreciated when several prototypes are required for a short production run, or when

products vary slightly in detail. The technology achieves this by using a robot to prepare a mold

directly from a CAD model, or from an existing spare part or artist’s model. Using the relevant

control data, the operator directs the robot to machine the shape into a mold made of hardened

sand, which is then cast in the normal way.

ConiferRob - Precision control:

Simtech Systems’ ConiferRob® precision software fills the processgap between machining path

generation systems, such as CAD systems,and industrial robots running machining

programs.ConiferRob ® can convert and move a machining program in *.apt format into a robot

for execution both quickly and safely. In addition to optimum accuracy, the positioning of work

pieces can also be easily designed and reviewed with the help of ConiferRob®– as its

reachability analysis options allow potential positioning problems to be identified and ensure that

the final positioning selected will work in practice.The technology can also be applied to other

areas ofmanufacturing that work with complicated shapes and extreme dimensions in materials

other than metal, such as plastic injection molding. Occupational safety is also improved, as

mold production takes place in a closed robot cell, which prevents the migration of potentially

hazardous particles into employees’ respiratory tract sand dust into ambient foundry air.

NileshsingRajput(Department Of Mechanical Engineering) Page 2

Fig 1.ConiferRobprogramme enables user to do robotic

offline machining with automatically optimized paths

together with very high precision collision detection.

FLOW-3D Cast software for foundries: FLOW-3D Cast is divided into different solver modules with increasing capabilities according to

the process. It also offers accessory modules for e.g. materials data and designing.FLOW-3D

Cast ® uses 3D CFD (computational fluid dynamic) simulation software as a calculation engine.

The program is based on the fundamental laws of mass, momentum and energy conservation. 3D

CFD has been supplied with a large variety of auxiliary physical models.

• Innovative Aspects: Very effective software in turbulence modeling oftwo phase flows - predict the sharp interface

between themolten metal and air during the filling. This is veryessential when the flow fronts are

breaking and smalldroplets are emerging into die cavity.Easy to use interface allowing operators

to use itwithout extensive training.Possibility to include allnecessary tools for casting

simulations.

• Main Advantages : Casting simulation using 3D CFD (computationalfluid dynamic) algorithms is becoming an

important part ofthe casting process in the modern foundry, allowing timeoptimization and cost

reduction by simulating what willhappen during the actual casting of molten metal at designtime,

experimenting alternative solutions without the needto set up trial and error.

REFERENCES:

[1] Sirviö, M. and Martikainen, H. “Simultaneous engineeringbetween workshops and

foundries” .Int. Conf. on BestPractices in the Production, Processing and Thermal

Treatment of Castings. Singapore, 10 - 12 Oct. 1995.

[2] Sirviö, M .andLouvo, A. “Use of simulated porosity foravoidance of casting defects”.

International GIFACongress Metal Casting '94 (GIFA '94). Dusseldorf, 18 June 1994

Functionally Graded Materials 2015-16

1 Annasaheb Dange College of Engineering and Technology, Ashta.

Functionally Graded Materials

SHIVRAJ NAGESH GURAV

[email protected]

Student, B.E. Mechanical Engineering, A.D.C.E.T, Ashta, Dist. Sangli, MS.

I. INTRODUCTION

Pure metals are of little use in

engineering applications because of the demand

of conflicting property requirement. For

example, an application may require a material

that is hard as well as ductile, there is no such

material existing in nature. To solve this

problem, combination (in molten state) of one

metal with other metals or non-metals is used.

This combination of materials in the molten state

is termed alloying (recently referred to as

conventional alloying) that gives a property that

is different from the parent materials. Bronze,

alloy of copper and tin, was the first alloy that

appears in human history. Bronze really

impacted the world at that time, it was a

landmark in human achievement and it is tagged

the ‘Bronze Age’ in about 4000 BC. Since then,

man has been experimenting with one form of

alloy or the other with the sole reason of

improving properties of material. There is limit

to which a material can be dissolved in a solution

of another material because of thermodynamic

equilibrium limit. When more quantity of the

alloying material is desired, then the traditional

alloying cannot be used. Another limitation of

conventional alloying is when alloying two

dissimilar materials with wide apart melting

temperatures; it becomes prohibitive to combine

these materials through this process. Powdered

Metallurgy (PM) is another method of producing

part that cannot be produced through the

conventional alloying, as alloys are produced in

powdered form and some of the problems

associated with the conventional alloying are

overcome. Despite the excellent characteristics

of powdered metallurgy, there exist some

limitations, which include: intricate shapes and

features that cannot be produced using PM; the

parts are porous and have poor strength.

ABSTRACT: In materials science functionally graded material (FGM) may be spotted by the variation in

composition and structure gradually over volume, resulting in corresponding changes in the properties of the

material. The overall properties of FMG are unique and different from any of the individual material that forms it.

There is a wide range of applications for FGM and it is expected to increase as the cost of material processing and

fabrication processes are reduced by improving these processes. In this article, an overview of fabrication processes,

area of application, some recent research studies and the need to focus more research effort on improving the most

promising FGM fabrication method (solid freeform SFF) is presented. Improving the performance of SFF processes

and extensive studies on material characterization on components produced will go a long way in bringing down the

manufacturing cost of FGM and increase productivity in this regard.

Functionally Graded Materials 2015-16

2 Annasaheb Dange College of Engineering and Technology, Ashta.

Although these limitations are of advantage to

some applications (e.g. filter and non structural

applications) but are detrimental to others.

Another method of producing materials with

combination of properties is by combining

materials in solid state, which is referred to as

composite material. Composite material are a

class of advanced material, made up of one or

more materials combined in solid states with

distinct physical and chemical properties.

Composite material offers an excellent

combination of properties which are different

from the individual parent materials and are also

lighter in weight. Wood is a composite material

from nature which consists of cellulose in a

matrix of lignin. Composite materials will fail

under extreme working conditions through a

process called delimitation (separation of fibers

from the matrix). This can happen for example,

in high temperature application where two

metals with different coefficient of expansion are

used. To solve this problem, researchers in Japan

in the mid 1980s, confronted with this challenge

in an hypersonic space plane project requiring a

thermal barrier (with outside temperature of

2000K and inside temperature of 1000K across

less than 10 mm thickness), came up with a

novel material called Functionally Graded

Material (FGM). Functionally Graded Material

(FGM), a revolutionary material, belongs to a

class of advanced materials with varying

properties over a changing dimension.

Functionally graded materials occur in nature as

bones, teeth etc., nature designed this materials

to meet their expected service requirements. This

idea is emulated from nature to solve engineering

problem the same way artificial neural network

is used to emulate human brain.

II. PROCESSING TECHNIQUES OF

FUNCTIONALLY

GRADED MATERIALS (FGM)

Thin functionally graded materials are usually in

the form of surface coatings, there are a wide

range of surface deposition processes to choose

from depending on the service requirement from

the process.

A. Vapor Deposition Technique

There are different types of vapor

deposition techniques, they include: sputter

deposition, Chemical Vapor Deposition (CVD)

and Physical Vapor Deposition (PVD). These

vapor deposition methods are used to deposit

functionally graded surface coatings and they

give excellent microstructure, but they can only

be used for depositing thin surface coating. They

are energy intensive and produce poisonous

gases as their byproducts. Other methods used in

producing functionally graded coating include:

plasma spraying, electro deposition, electro-

phoretic, Ion Beam Assisted Deposition (IBAD),

Self Propagating High-temperature Synthesis

(SHS), etc. All the above mentioned processes

cannot be used to produce bulk FGM because

they are generally slow and energy intensive,

therefore they are uneconomical to be used in

producing bulk FGM.:

B. Powder Metallurgy (PM)

Powder metallurgy (PM) technique is used to

produce functionally graded material through

three basic steps namely: weighing and mixing

of powder according to the pre designed spatial

Functionally Graded Materials 2015-16

3 Annasaheb Dange College of Engineering and Technology, Ashta.

distribution as dictated by the functional

requirement, stacking and ramming of the

premixed-powders, and finally sintering. PM

technique gives rise to a stepwise structure. If

continuous structure is desired, then centrifugal

method is used.

C. Centrifugal Method

Centrifugal method is similar to centrifugal

casting where the force of gravity is used

through spinning of the mould to form bulk

functionally graded material. The graded

material is produced in this way because of the

difference in material densities and the spinning

of the mould. There are other similar processes

like centrifugal method in the literature (e.g.

gravity method, etc.). Although continuous

grading can be achieved using centrifugal

method but only cylindrical shapes can be

formed. Another problem of centrifugal method

is that there is limit to which type of gradient can

be produced because the gradient is formed

through natural process (centrifugal force and

density difference). To solve these problems,

researchers are using alternative manufacturing

method known as solid freeform.

D. Solid Freeform (SFF) Fabrication Method

Solid freeform is an additive manufacturing

process that offers lots of advantages that

include: higher speed of production, less energy

intensive, maximum material utilization, ability

to produce complex shapes and design freedom

as parts are produced directly from CAD (e.g.

AutoCAD) data. SFF involves five basic steps:

generation of CAD data from the software like

AutoCAD, Solid edge etc, conversion of the

CAD data to Standard Triangulation Language

(STL) file, slicing of the STL into two

dimensional cross-section profiles, building of

the component layer by layer, and lastly removal

and finishing.

III. FUTURE RESEARCH DIRECTION

Functionally graded material is an

excellent advanced material that will

revolutionize the manufacturing world in the

21st century. Cost is a major problem, with

substantial part of the cost expended on powder

processing and fabrication method. Solid

freeform fabrication technique offers a greater

advantage for producing FGM. More research

needs to be conducted on improving the

performance of SFF processes through extensive

characterization of functionally graded material

in other to generate a comprehensive database

and to develop a predictive model for proper

process control. Further work should also be

done to improve the process control through

development of more powerful feedback control

for overall FMG fabrication process

improvement (i.e. full automation). This will

improve the overall performance of the process,

bring down the cost of FGM and improve

reliability of the fabrication process.

References:

[1] Bever MB, Duwez PE (1972) Gradients in

composite materials. Mater Sci Eng 10(1):1:8

[2] Shen M, Bever MB (1972) Gradients in

polymeric materials. J Mater Sci 7(7):741-746

[3] Lee WY, Bae YW, More KL (1995)

Synthesis of functionally graded metal-ceramic

microstructures by chemical vapor deposition. J

Mater Res 10(12):3000-3002

DEVENDRA S. PATIL (BE Mechanical)

Honda’s new eight-speed DCT

Dual-clutch transmission-essentially

two parallel gearboxes that hand off

power from one to the other, and do

it more efficiently and quicker than

either planetary automatics or

conventional manual transmission-

seem like a dream technology for

engineers seeking both performance

and fuel economy.

But computer management of

their clutches is tricky, and drivers

are regular to the silky launch

provided by a torque-equipped

planetary automatic or frequently

disappointed by the driving

dynamics of DCT’s. The cars can

lurch when trying to move at

parking lot speed, and a DCT can

make inch-perfect parallel parking

frustrating.

Honda has traditionally build

its own automatic transmission

(uniquely without planetary gear

uses a torque converter

set), a strategy that has led to its

transmissions sometimes falling

behind industry fashion. In the case

of Acura TSX, that meant only five

speeds at a time when six is standard

and nine-speed automatics are

available.

The 2015 Acura TLX replaces

the TSX and the more on the TL,

and offers a ZF-sourced nine-speed

automatic transmission with the

optional 3.5-L V6. The base car

pairs its 2.4-L l4 with a Honda-

developed eight-speed DCT, which

features the novel twist of a torque

converter in place of a clutch. Honda

claims it’s the first production DCT

so equipped.

This gives the DCT-equipped

TLX the smooth low-speed driving

dynamics of a traditional automatic

transmission with a gearbox that is

more efficient, according to Chris

Kipfer, the Assistant Large Project

Manager responsible for drivetrain.

Honda’s product planners and

engineers interviewed drivers of car

equipped with DCTs, and “the main

thing they talked about was how

unrefined and unsporting they are,”

said Kipfer. “The main issue is the

low-speed launch.”

DEVENDRA S. PATIL (BE Mechanical)

Incorporating a torque

converter into the unit not only

provides some internal benefits that

helps deliver the low-speed

refinement most drivers seek but its

inherent torque multiplication

boosts-off-the-line acceleration. In

fact, the TLX 2.4-L car accelerates

to 60mph 1.5s faster than the TSX

did, thanks in large part to the use of

a torque converter, he noted.

The torque converter, supplied

by Cardington Yutaka Technologies,

Inc., is more expensive than a clutch

for the same application. But DCT

clutches demand use of the more

costly dual-mass flywheel, so the

torque converter solution is no more

expensive overall, according to

Kipfer.

The eight-speed’s additional

ratios permit a much wider ratio

spread than the old five-speed

automatic, contributing to the

speedier acceleration and improved

fuel efficiency. Where the old five-

speed’s lowest gear was an 11:1

ratio, the TLX’s DCT launches with

a 14:1 ratio.

The DCT’s first seven ratios

are all lower than those in the old

automatic, while the eight gear’s

2.212:1 ratio is higher than the

2.512:1 of the old one, for better

highway fuel efficiency. This wider

ratio spread contributes, along with

changes to the engine, to the TLX’s

four-cylinder scoring 2 mpg higher

on the U.S. EPA’s city driving cycle

and 4 mpg higher on the highway

test.

The engineer team’s biggest

task in developing the DCT was to

optimize the transmission’s ability to

change gears quickly, without

hammering the car’s occupants with

hard upshifts, said Kipfer.

“It was getting the feeling just

right and making sure they are quick

shifts without shocks,” he explained.

The Honda-build DCT upshifts 33%

faster than the five-speed automatic

used in the outgoing TSX.

References:

-Technology Report, Automotive

Engineering, SAE sections,

September 2, 2014.

Magazine.sae.org/auto.

nanofluids in heat transfer 2015

Sonali Kadam T.E.A Page 1

Cooling is one of the most

important technical challenge facing

by diverse industries, including

microelectronics, transportation,

solid- state lighting, and

manufacturing. Technological

developments such as microelectronic

devices with smaller features and

faster operating speeds, higher power

engines, and brighter optical devices

driving increased thermal loads

,required advances in cooling. The

conventional method for increasing

heat transfer rate is to increase the

area available for exchanging heat

with a heat transfer fluid . however

this approach requires an undesirable

increase in thermal management

system’s size. There is therefore

urgent need for new and innovative

coolants with improved performance.

The novel concept of ‘nanofluids’-

Nanofluids are dilute liquid

suspensions of nanoparticles with at

least one of their principal dimensions

smaller than 100 nm

Flowing Properties of nanoparticles

which make them suitable for heat

transfer:

1.higher heat conduction : the large

surface area of nanoparticles allows

for more heat transfer.

2.stabilty: because the particles are

small, they weigh less ,and chances of

sedimentation are also less. This

overcome the drawback of

suspensions, setlling of particles.

3.microchannel cooling without

clogging: they are also ideal for

microchannel applications where

high heat rates are encountered.

4. reduced chances of erosion : as

they are very small , momentum they

can import to soli wall is very smaller.

This reduces the chances of erosoin of

components.

5. small concentrations and

Newtonian behavior : large

enhancement in thermal conductivity

is achieved by the small concentration

of paticles, the rise in viscosity is

nominal; hence, pressure drop was

increased marginally.

nanofluids in heat transfer 2015

Sonali Kadam T.E.A Page 2

2. Preparation of nanofluids

The nanofluid does not simply

refer to a liquid+solid mixture. Some

special requirements are necessary,

such as even suspension, stable

suspension, durable suspension, low

agglomeration of particles, no

chemical change of the fluid. In

general, these are e€ective methods

used for preparation of suspensions:

(1) to change the pH value of

suspensions;

(2) to use surface activators and/or

dispersants;

(3) to use ultrasonic vibration.

All these techniques aim at changing

the surface properties of suspended

particles and suppressing formation of

particles cluster in order to obtain

stabile suspensions. The common

activators and dispersants are thiols,

oleic acid, laurate salts. While

preparing the suspensions, diferent

types and percentages of activators or

dispersants have been tried and tested.

After the suspension has been

vibrated in a ultrasonic vibrator, the

stabile suspension can last more than

30 h in the stationary state.

in recent studies it is found that heat

transfer coefficients of magnetite

nanofluids were increased up to

300%when local magnetic field was

applied. In typical nanofluids, the

nanoparticals are uniformly dispersed.

In solution of magnetic nanofluids,

however, the particles can be

controlled by using external magnetic

field, which enhance their thermal

conductivity.

It was reported by many of the

researchers that the increase in the

effective thermal conductivity and

huge chaotic movement of

nanoparticles with increasing particle

concentration is mainly responsible

for heat transfer enhancement.

However, there exists aplenty

of controversy and inconsistency

among the reported results. The

outcome of all heat transfer works

using nanofluids showed that our

current understanding on nanofluids is

still quite limited. There are a number

of challenges facing the nanofluids

community ranging from formulation,

practical application to mechanism

understanding. Engineering suitable

nanofluids with controlled particle

size and morphology for heat transfer

applications is still a big challenge.

REFERENCES:

[1] Sarit k. Das, Nandy

Putra,Wailfried Roetzel.Pool Boiling

Characterstics Of Nanofluides.

[2]Stefen U.S.Choi,

J.A.Estaman Enhancing thermal

conductivity of fluids with

nanoparticles

[3]Yimin Xuan, Wilried

Roetzel, Concepion of heat transfer

correlation for heat transfer.

nanofluids in heat transfer 2015

Sonali Kadam T.E.A Page 3

PRATIK DESHMUKH T.E. A ADCET

1

THERMOELECTRIC REFRIGERATION SYSTEM

Abstract

Refrigeration is a process in which work is done to move heat from one location to

another. The work of heat transport is traditionally driven by mechanical work, but can also be

driven by magnetism, laser or other means. A thermoelectric refrigerator in the same way is a

refrigerator that uses the Peltier effect to create a heat flux between the junction of two different

types of materials. TEC also called as Peltier cooler is a solid state heat pump which transfers

heat from one side of the device to the other side against the temperature gradient (from cold to

hot), with consumption of electrical energy. However it is not used conventionally because of its

low efficiency.

Introduction

In 1821, Thomas Seeback discovered that a continuously flowing current is created when

two wires of different materials are joined together and heated at one end. This idea is known as

the seeback effect. The seeback effect has two main applications including temperature

measurement and power generation. Thirteen years later Jean Charles Athanase reversed the

flow of electrons in seeback.s circuit to create refrigeration. This effect is known as the Peltier

Effect. This idea forms the basis for the Thermoelectric refrigerator.Scottish scientist

WilliamThomson (later Lord Kelvin) discovered in 1854 that if a temperature difference exists

between any two points of a current carrying conductor, heat is either evolved or absorbed

depending upon the material.6 If such a circuit absorbs heat, then heat may be evolved if the

direction of the current or of the temperature gradient is reversed. The Peltier effect is a

temperature difference created by applying a voltage between two electrodes connected to a

sample of semiconductor material. This phenomenon can be useful when it is necessary to

transfer heat from one medium to another on a small scale. The Peltier effect is one of three

types of thermoelectric effect; the other two are the seeback effect and the Thomson effect. In a

Peltier-effect device, the electrodes are typically made of a metal with excellent electrical

conductivity. The semiconductor material between the electrodes creates two junctions between

dissimilar materials, which, in turn, creates a pair of thermocouple voltage is applied to the

electrodes to force electrical current through the semiconductor, thermal energy flows in the

direction of the charge carriers. In its simplest form, this may be done with a single

semiconductor 'pellet' which is soldered to electrically-conductive material on each end (usually

plated copper). In this 'stripped-down' configuration, the second dissimilar material required for

the Peltier effect, is actually the copper connection paths to the power supply. It is important to

note that the heat will be moved (or 'pumped') in the direction of charge carrier flow throughout

the circuit— actually, it is the charge carriers that transfer the heat. But in order to pump

appreciable amount of heat, we need to interconnect such semiconductor electrically and

thermally parallel. Moreover it needs costly power supply arrangement to supply high current

requirement for parallel arrangement of semiconductor. So semiconductor can be arranged

electrically in series but thermally parallel which further increases the possibility of short

circuiting and reduces the reliability of system. The best optimized way to connect the

semiconductor is in the form of pn junctions which overcome the above mentioned problems.

PRATIK DESHMUKH T.E. A ADCET

2

Circuit diagram

REFERENCES

� WIKIPEDIA

� www.sjtuirc.sjtu.edu.cn/jpkc/ziyuan/zhil3.pdf

1

AKSHAY DHANAWADE

T.E. A

ADCET, ASHTA

Virtual Manufacturing

The research area “Virtual Manufacturing” can be defined as an integrated manufacturing

environment which can enhance one or several levels of decision and control in

manufacturing process. Several domains can be addressed: Product and Process Design,

Process and Production Planning, Machine Tool, Robot and Manufacturing System. As

automation technologies such as CAD/CAM have substantially shortened the time required to

design products, Virtual Manufacturing will have a similar effect on the manufacturing phase

thanks to the modelling, simulation and optimisation of the product and the processes

involved in its fabrication.

Manufacturing is an indispensable part of the economy and is the central activity that

encompasses product, process, resources and plant. Nowadays products are more and more

complex, processes are highly-sophisticated and use micro-technology and the market demand

evolves rapidly so that we need a flexible and agile production

In this complex and evolutive environment, industrialists must know about their processes

before trying them in order to get it right the first time. To achieve this goal, the use of a

virtual manufacturing environment will provide a computer-based environment to simulate

individual manufacturing processes and the total manufacturing enterprise. Virtual

Manufacturing systems enable early optimization of cost, quality and time drivers, achieve

integrated product, process and resource design and finally achieve early consideration of

producibility and affordability.

Virtual manufacturing will contribute to the following benefits:

1. Quality: Design For Manufacturing and higher quality of the tools and work instructions

available to support production.

2. Shorter cycle time: increase the ability to go directly into production without false starts.

3. Producibility: Optimise the design of the manufacturing system in coordination with the

product design; first article production that is trouble-free, high quality, involves no reworks

and meets requirements.

4. Flexibility: Execute product changeovers rapidly, mix production of different products,

return to producing previously shelved products.

5. Responsiveness: respond to customer about the impact of various funding profiles and

delivery schedule with improved accuracy and timeless.

6. Customer relations: improved relations through the increased participation of the customer

in the Integrated Product Process Development process.

2

AKSHAY DHANAWADE

T.E. A

ADCET, ASHTA

CONCLUSION

As a conclusion of this paper, we can say that we have now reached a point where everyone

can use VM. It appears that VM will stimulate the need to design both for manufacturability

and manufacturing efficiency. Nowadays, even if there is a lot of work to do, all the pieces are

in place for virtual Manufacturing to become a standard tool for the design to manufacturing

process: computer technology is widely used and accepted, the concept of virtual prototyping

is widely accepted, companies need faster solutions for cost / time saving, for more accurate

simulations, leading companies are already demonstrating then successful use of virtual

manufacturing techniques. Nevertheless, we have to note that there are still some drawbacks

to overcome for a complete integration of VM techniques : data integrity, training, system

integration.

REFERENCES

1. Wikipedia – Virtual Manufacturing

2. www.arxiv.org

1

GOPAL GAWALI ADCET , ASHTAT.E. A

New Wind Turbine Generates Electricity Without Rotating Blades

A Spanish company called Vortex Bladeless has produced a wind turbine that takes advantage of

the vortices produced when wind moves around an obstacle.This new wind turbine wobbles

elegantly in the wind, generating electricity without rotating blades.

“It looks like asparagus,” says David Suriol, one of the founders.If you put any object in the path of

the wind, it will create an undulating vortex behind the barrier. This is a problem that has plagued

engineers for years: bridges have fallen due to wind eddies.

Vortex Bladeless engineers have designed their turbine to take advantage of this vortex. The thin,

cone-shaped turbine is made of carbon fiber and fiberglass with the motor at the bottom instead of

the top (like traditional turbines) to improve sturdiness. The design ensures that the wind's vortex

spins synchronously along the entire cone. There is also a ring of magnets at the base of the cone

that give the rotations a boost regardless of wind speed.

There are many advantages to the new Vortex design=It is cheaper to manufacture than current

pinwheel turbines. Maintenance prices are also lower because there is no friction from

mechanically moving parts, which reduces the need for oiling and bolt replacement. It is

completely silent and birds can fly around them safely.

2

GOPAL GAWALI ADCET , ASHTAT.E. A

The Vortex device has been computationally modeled, tested in a wind tunnel, and there are

prototypes out in the open, but details on tests carried out by the company or independent labs are

currently scant. It is also not the first wind turbine to take advantage of oscillatory technology.

Researchers in the '80s found that the swirling oscillations were too random for reliable power

generation, and the speed of oscillations put a lot of stress on the structure and caused it to break

down unexpectedly.

The Vortex has the same goals as conventional wind turbines: To turn breezes into kinetic energy

that can be used as electricity. Vortex’s lightweight cylinder design has no gears or bearings. The

company has received $1 million in private capital and government funding in Spain and is seeking

another $5 million in venture capital funding. Yáñez says the company plans to release a four-

kilowatt system in 2016 and a much larger one-megawatt device around 2018.

Instead of capturing energy via the circular motion of a propeller, the Vortex takes advantage of

what’s known as vorticity, an aerodynamic effect that produces a pattern of spinning vortices.

Vorticity has long been considered the enemy of architects and engineers, who actively try to

design their way around these whirlpools of wind.

In its current prototype, the elongated cone is made from a composite of fiberglass and carbon

fiber, which allows the mast to vibrate as much as possible. At the base of the cone are two rings of

repelling magnets, which act as a sort of nonelectrical motor. When the cone oscillates one way,

the repelling magnets pull it in the other direction, like a slight nudge to boost the mast’s

movement regardless of wind speed. This kinetic energy is then converted into electricity via an

alternator that multiplies the frequency of the mast’s oscillation to improve the energy-gathering

efficiency.

3

GOPAL GAWALI ADCET , ASHTAT.E. A

Its makers boast the fact that there are no gears, bolts, or mechanically moving parts, which they

say makes the Vortex cheaper to manufacture and maintain. The founders claim their Vortex Mini,

which stands at around 41 feet tall, can capture up to 40 percent of the wind’s power during ideal

conditions. Based on field testing, the Mini ultimately captures 30 percent less than conventional

wind turbines, but that shortcoming is compensated by the fact that you can put double the Vortex

turbines into the same space as a propeller turbine.

REFERENCES

1. WIKIPEDIA

2. www.arising.com