final report engineering 2011

8/6/2019 Final Report Engineering 2011

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Design of Flame Eating Sterling Engine

By Reverse Engineering

ME 605 DESIGN AND FABRICATION PROJECT

DEPARTMENT OF MECHANICAL ENGINEERING

Researched & Submitted by

VIGNESH.M

TAKSHINAMURTHY.A.A

K. VIJAY KUMAR

SUKUMARAN.V

VISHNU VARDHAN REDDY

MEENAKSHI ACADEMY OF HIGHER EDUCATION ANDRESEARCH FACULTY OF ENGINEERING AND TECHNOLOGY,

CHENNAI 600 069

JUNE 2011

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MEENAKSHI ACADEMY OF HIGHER EDUCATION AND

RESEARCH FACULTY OF ENGINEERING AND TECHNOLOGY

CHENNAI 600 069

BONAFIDE CERTIFICATE

Certified that this mini project report titled Fabrication of Flame Eating Sterling Engine

Is the bonafide work done by

VIGNESH.M -6508412

TAKSHINAMURTHY.A.A - 6508408

K. VIJAY KUMAR -6508413

SUKUMARAN.V -6508406

VISHNU VARDHAN REDDY.V -6508411

Who carried out the project work under my supervision.

SIGNATURE SIGNATURE

Mr. C .Krishnamurthy, Mr. M .Gopinath,

SUPERVISOR HEAD OF THE DEPARTMENT

Department of Mechanical Engg, Department of Mechanical Engg,

Submitted for the Meenakshi Academy of Higher Education and Research, FET,

Examination held on

INTERNAL EXAMINER EXTERNAL EXAMINER

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ACKNOWLEDGEMENT

This project work has given an adequate knowledge and exposure in my mechanical engineering

core field and the art of designing and fabricating manufacturing components wherein I come out

with The Fabrication of Flame Eating Sterling Engine.

The team hopes that this exposure and knowledge will help in building up of our foundation in

mechanical engineering field in scope of bright carrier. The team acknowledges the help

extended by the management, Meenakshi Academy of Higher Education and Research,

Faculty of Engineering and Technology for granting permission at all point to do our project.

We thank all those who had come forward to share their intellectual knowledge and guidance to

complete our project work very successfully.

We extend our hearty thanks to all our teachers and our technical staff and who were behind us

and for their timely help in the successful completion of this project work.

We express our sincere thanks to our respected Dean Dr.T.Manvelraj for giving us the

opportunity in making our project and for his encouragement in completion of our project.

We offer our foremost thanks to our respected Head of Department of Mechanical Engineering,

Mr. Gopinath for his help in all time to complete our project work.

We express our sincere thanks to our project guide Mr.C.Krishnamurthy, lecturer, departmentof mechanical engineering for his valuable guidance and help in carrying out this project.

Finally we thank all non-teaching faculty members those who have contributed their work forsuccessful completion of this project.

The team and this project would have not been a success without the special team mate. WethankMr.R.Murthy CEO-Bala Industries who spent his most valuable time for the making of

this project in his very busy schedule.

The team whole heartedly thanks Mrs.Padmashree Murthy for comforting us, providing lunch

and health appetizers, every time we work in their industry for the making of this project.

Contents

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Topic Page Number

Cover Page 1

Bonafide Certificate 2

Acknowledgement 3

Special Thanks 4

Contents 5

Abstract5

Ethics Statement and Signatures 7

Literature Survey 8

History 9

Sterling Engine Configurations 12

Project Formulation 14

Constraints and Other Considerations 15

Feasibility Assessment 16

Discussion 17

Conceptual Design 18

The Gas Laws 19

Final Engine Design 21

Engine Adiabatic Analysis 23

Material Selection 24

Reasons to use a Sterling Engine 26

Analyze from Economic point 28

Applications of the Sterling power 30

Design Considerations 37

Project Management 38

Cost Analysis 39

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Process Carried 40

Reverse Engineering 41

Design Considerations and Future Work 43

Lessons Learned

44

Figures Through SW2010 45

Conclusion 48

Bibliography 51

ABSTRACT

In order to develop a compact and low cost Sterling engine, a gamma type Sterling

engine with simple moving-tube-type heat exchangers and a rhombic mechanism

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was developed. Its target shaft power was 50 W at engine speed of 250 rpm and

mean pressure of 0.8 MPa. This paper describes the outline of the engine design

and the performance test. The test was done without load, using air in atmospheric

condition. Also, a mechanical loss measurement was also done in highly

pressurized condition, in which the engine was driven by a motor compulsory.Then, methods to get higher performance was considered based on the comparison

of experimental and calculated results. The results indicate that a higher

performance heat exchanger and decreasing of mechanical loss are needed for the

attainment of the target performance.

Key words: Sterling engine, Alpha type, Beta type, Gamma type, Overlap

Volume, Schmidt Analysis.

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Ethics Statement and Signatures

The work submitted in this project is solely prepared by a team consisting of

Vignesh.M, Takshina Murthy.A.A, Vijay Kumar.K, Vishnu Varadhan Reddy.V

and Sukumaran.V and it is original. Excerpts from others' work have been clearlyidentified, their work acknowledged within the text and listed in the list of

references. All of the engineering drawings, computer programs, formulations,

design work, prototype development and testing reported in these documents are

also original and prepared by the same team of students.

Literature Survey

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Sterling engines are external combustion engines which can function by using a

wide variety of fuel sources such as a combustible gas, nuclear head, or solar

energy. The heat supplied to the engine causes the working fluid to expand;

thereby, moving a displacer piston. This piston then displaces the working fluidfrom the hot end into the cold end of the engine where the working fluid is

compressed and the piston retracts. The displacer piston then moves the fluid into

the hot end where it will once be expanded and then displaced into the cold end

where it will compress and this cycle will continue as long the temperature

difference exists. The Sterling cycle is a reversible cycle which closely follows the

Carnot principal, making it a highly efficient cycle. Sterling engines are the

simplest form of heat engine and are arguably the most efficient engine

(Berchowitz, 1984).

History

The first patent containing a Sterling engine was written in 1816 by the Rev'd Dr.

Robert Sterling. He patented an economizer which is synonymous with todays

regenerator, used to increase the efficiency of the engine. The Sterling engine did

not gain wide popularity compared to the steam engine due to the limits that

currently available materials offered. Sterling engines went relatively unnoticed

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and not improved on until the late 1930 when Philips selected Sterling engines to

power radios for remote areas. The decision to use Sterling was based on its low

audible and E&M noise and ability to run on any heat source from heating oil to

wood (Berchowitz, 1984).

The original Sterling Engine patent of 1816

In 1972 Ford Motor Company teamed up with Philips to develop an automotive

Sterling engine, and gage its potential for automobiles. What was produced was a

four cylinder, 170 Horse Power Sterling engines which used a swash plate to

transfer the power from the Sterling engines into torque that could be connected to

a traditional transmission. The engine ended up having little potential for use in

automobiles due to the nature of external combustion engines inability to produce

immediate power.

There is however concepts to revive the automobile Sterling engine for use inhybrid electric vehicles because of its higher power to weight ratio and overall

efficiency (Nightingale, 1986)

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Automotive Sterling Engine

Beginning in the 1970 s NASA s Glenn Research Center began investigations and

development of high efficiency Sterling engines to be used in space applications.

The decision to use Sterling engines was centered on their relative reliability

compared to other mechanical engines, simplicity, low noise (audible, E&M),

essentially nonexistent vibration (when convertors were paired), and most

importantly high power to weight ratio. The Brayton Rotating Unit (BRU) Project

aim at obtaining higher efficiency power conversion system for isotope, reactor,

and solar receiver hear sources (Lee Mason, 2007).

NASA is now taking a serious interest in Sterling engines for their potential use on

other planetary bodies. One of the most prominent possibilities is the use of a

Sterling-based Fission Surface Power System which can generate power of about

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Brayton Rotating Unit(BRU)


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50kWe per unit. This form of power generation is a viable solution to the

monumental problem of attempting a manned mission to the Lunar and Martian

Surfaces for extended periods of time. This type of system could be used to

provide power for rovers, remote science experiments, or as a utility power source

for an outpost in any of our celestial orbiting bodies (Lee Mason, 2007).

Sterling based Fission Surface Power System

Sterling Engine Configurations

Sterling engines are commonly found in three different configurations; alpha, beta,

and gamma. There is also a variation of each one named free-piston but due to its

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complexity and high cost, it will not be discussed in details for this project. Each of

the three main configurations has unique advantages and disadvantages due their

variation in geometry and arrangement.

An Alpha Sterling engine is composed of two power pistons which are housed in

two separate cylinders where one cylinder is exposed to heat while the

second is subjected to cold and heat dissipation. Alpha Sterling engines will

sometimes utilize a regenerator as part of its configuration. The regenerator

function is to store heat as it moves from the hot end to the cold one and re-

supplying the fluid with heat as it returns to the hot end.

Alpha Sterling Engine

A Beta Sterling Engine configuration uses one cylinder which houses both the

power and displacement piston. The displacer piston purpose is to shuffle the air

between the hot end and the cold end while not extracting any power from the

expanding gas.

Beta Sterling Engine

Lastly, a Gamma Sterling engine is similar to a Beta configuration

expect save for the power piston which is housed in a separate cylinder but still

connected to the same flywheel as the displacer piston.

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Gamma Sterling Engine

Modern Era

Changes to the configuration of mechanical Sterling engine interest engineers and

inventors who create a lot of different version of the engine. There is also a large

those with liquid pistons and those with diaphragms as pistons. For example, as an

alternative to the mechanical Sterling engine is the fluidyne pump, which uses theSterling cycle via a hydraulic piston. In its most basic form it contains a working

gas, a liquid and two non fluidyne goes into pumping the liquid.

Project Formulation

Overview

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The overall goal of this project is to conceptualize, design, and build a modified

Rhombic Sterling engine with a De-neutralized Alcohol as a heat source

concentrator.

Project ObjectivesThis Rhombic Sterling engine uses a beta configuration. This project will beconsidered a success if the following objectives are met. Firstly, a design is to be

made of a beta Sterling engine which uses a cost effective means of producing the

most electricity. This engine should have a large margin of positive net energy and

net power to be considered a feasible application.

Second, a proof-of-concept of this configuration should be demonstrated by the

creation of a small scale prototype. Lastly, this design should prove itself to be

flexible and scalable to fit the needs of varying applications such as use in remote

areas and disaster relief.

Design SpecificationsIn order to meet the objectives of this project, certain specifications need to be

ascertained. Due to the nature of Sterling engines, the maximum efficiency is

achieved when the temperature difference between the hot end and the cold end is

sufficiently large. Therefore, the design specifications focused on achieving this

goal. The De-neutralized heat source used in this project is to be sufficiently

powerful to concentrate heat on the surface of the engine without noticeable losses

due to medium, and geometry. The material used for the cylinders, pistons, and

flywheel should be able to withstand thermal cyclic loading at the high operatingtemperature without causing the material to weaken, undergo chemical changes, or

fail. The extended surfaces used in the cold end of the engine to dissipate heat

should be of such geometry and material that heat transfer would be maximized

between the engine and the ambient fluid.

Constraints and Other Considerations

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The major constraint of Sterling engines is the ability to generate enough heat on

the hot end while cooling the cold end in order to produce the necessary change in

temperature so that power generation in feasible. Therefore, the main constraint of

this design is its ability to concentrate enough heat on the hot end while chilling the

cold end.

The amount of heat that can be supplied is dependent on a few factors, some of

which can be controlled by the design and some of which are outside of the

engineering design scope. Such factors that are outside of our control are the

position of the engine relative to the Earth and the climate of that region. Due to

the constraints of the heat in the operating region, the most important consideration

when conceptualizing the engine is the optimization of the spirit lamp

concentrator.

In the event of low heat, the efficiency of the engine could be optimized by the

following factors which work to counteract the loss due to the availability of the

heat.The efficiency of the engine can be improved significantly by selecting effective

extended finned surfaces to assist in the heat dissipation from the cold end. This

will cause the cold end temperature to be significantly lower than the heat on the

hot end and increase the change in temperature. Another way to increase efficiency

is to select a working fluid within the cylinder which can adequately transfer heat.

Feasibility Assessment

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This project is feasible because similar technologies have been produced earlier.

The method of generating power via spirit lamp, though still at its infancy, is very

reliable and efficient.

Our design differs in several ways. First, our design includes a de-natured alcoholas the heat source instead of any other fuels. Perhaps most unique about this

configuration is our heat dissipation system and our internalization of the

components. The most famous Rhombic Sterling application uses a water pump to

cool the engines. Since we don not want to lose any power, the stream of air from

already existing atmosphere will cool the engine. This type of cooling technology

is commonly used with nuclear power plants so it has been proven successful. The

most interesting feature of our Sterling engine that has never been done before is

the internalizing of the components. This method will be tested and if proven

successful, will have many positive applications for heat engines working in harsh

environments.

The Carnot efficiency for our engine is 69%; this is based on a 975K hot end

temperature and a 300K cold end temperature.

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Discussion

This senior design project will conceptualize, design, and modify a Rhombic

Sterling engine for power generation for remote areas and/or disaster relief. TheSterling engine will be a beta configuration with a power capacity equal to the

amount the heat collector harvests. This power capacity will be achieved via the

use of a spirit lamp concentrator large enough to supply the hot end with

sufficient heat and by generating a cold end which can efficiently dissipate heat

into the atmosphere or working fluid in order to produce the needed change in

temperature to create the volume changes in the cylinder. The efficiency of the

engine can be maximized by selecting appropriate fins and extended surfaces

as well as accurately focusing flame on the hot end.

One of the largest areas that need improvement in heat engines is the

thermal losses of the engine to the surroundings. A innovative way in which this

problem can be addressed is thorough the implementation of Aerogels. This

light-weight material currently holds the world title for the lowest density solid in

history, measuring in at 1.9mg/cm3

Aerogels are extremely porous material and can be as much as 99.8% air. Its

mesoporousity is an invaluable ally against heat loss due to convection,

conduction, and radiation. The use of Aerogels as a high-temperature, low-weight

alternative to traditional insulation will yield an engine that has less heat lossdue to heat transfer as well as maintaining the low weight necessary needed for

the Flame Sterling applications.

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Conceptual Design

Sterling engines provide a huge advantage over other heat engines based on their

power outputs. Due to the relatively low expected temperature differences, theSterling engine was chosen to be of beta configuration. In order to improve

efficiencies of the engine, the temperature difference needs to be at a maximum. It

is for this reason that the cold end of the engine would be altered to increase the

heat transfer rate and heat dissipation from the engine.

For Sterling engines, friction is their biggest enemy, especially with low

temperature difference engines. For this reason, the engines flywheel was

internalized and place within the displacer piston. This allows for the flame to get

converted to thermal energy, then mechanical energy, which is finally converted to

useful electrical energy.

Due to the multitude of conversion in the system, any and all steps to increase

efficiencies will be taken. In addition to the engines modification and the

internalization of the flywheel, the Sterling engine will also be designed to

minimize all possible dead volume. This is the biggest enemy within Sterling

and it something that needs to be closely monitored. For this reason, the

displacer piston and the power piston were designed to reduce as much dead

volume as possible with very small tolerances.

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The Gas Laws

There are three equations called the gas laws which govern the relationships

between the thermodynamic temperature, the absolute pressure and the volume ofgasses.

The first equation is called Boyles Law which describes the inverse relationship

between pressure and volume in a closed system if the temperature remains

constant.

Boyles Law states that: (P1) (V1) = (P2) (V2)

The second is called Gay-Lussac's Law which describes the relationship between

temperature and pressure if the volume is constant.

Gay-Lussac's Law states that: (P1/T1) = (P2/T2)

The third equation is called Charles's Law which describes the relationship

between Volume and Temperature if the pressure is constant.

Charle's Law states that: (V1/T1) = (V2/T2)

These three Laws can be used to make the Combined Gas Law which relates allthree properties to each other.

Combined Gas Law states that: [(P1V1)/T1]=[(P2V2)/T2]

Nicolas Leonard Sadi Carnot came up with the Carnot cycle which is a

thermodynamic cycle based on the hypothetical Carnot heat engine. An engine

capable of performing like a Carnot engine would be very efficient. The Carnot

cycle describes the perfect cycle of the working fluid. This can be shown on a

Temperature Entropy (T-s) diagram as shown below.

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However due to material and gas restrictions the chances of the Sterling engine

ever reaching this perfection are very low.

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Final Engine Design

Geometry of Heater Volume

The overall volume for the heater is prescribed to be 70 cubic centimeters, about

4.3 cubic centimeters. The inside diameter of the body of the engine is 1 inch,giving us inch height before we surpass our volume allocation. Through the use

of 33% volume ratio wire mesh we can increase the overall height of the heater, as

well as increase the surface area for heat transfer. Implementing the 33%

volume mesh the heater height comes to 3/8 inches.

Geometry of Expansion Volume

The overall expansion volume for the engine is prescribed to be 63 cubic

centimeters, about 3.9 cubic centimeters. The inside diameter of the body of the

engine is 1 inch, giving us 1/4 inch height before we surpass our volumeallocation.

Geometry of Cooler Volume

The overall expansion volume for the engine is prescribed to be 13 cubic

centimeters, about 0.8 cubic inches. The inside diameter of the cold end of the

engine is 1 inch, giving us 1/4 inch height before we surpass our volume

allocation.

Geometry of Compression Volume

The overall compression volume for the engine is prescribed to be 63 cubiccentimeters, about 3.9 cubic centimeters. The inside diameter of the cold end of the

engine is 1 inch, giving us inch height before we surpass the total length of

the cold end. The rest of the volume, 2.1 cubic inches will be allocated to

the bottom inch of the displacer piston.

Design of Crankshaft

The crankshaft was designed to accomplish the sweep distance for both the power

piston and the displacer piston. For both pistons, the sweep distance is inch.

The displacer piston had two rod connections to the crankshaft, equallyspaced from the central rod connection to the power piston. The diameter of

the crankshaft should be capable of handling the expected loads transferred from

the rods, which is expected to be 100 kg from the power piston, and 1 pound from

the displacer piston based on a zero weight assumption. The crankshaft is expected

to rotate at 250 RPM, based on literature review of like engines (similar volume

and power output).

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Design of Rods

The rods were designed to withstand the maximum loading expected in the

engine. For the power piston, this is the cross sectional area multiplied the

maximum pressure of the engine, which comes to approximately 1400 pounds.

Operating pressure

The equation set used to find the pressure is contained within the engineering

analysis portion of the report. The resulting pressure is 1.7 Mpa (200 psi).

Working Fluid

The working fluid chosen for the Sterling engine is high temperature lubricated oil.

High temperature lubricated oil was chosen because of its cost, non-toxicity, and

elimination for the need of environmental controls.

Mass of Working fluid

The mass of the working fluid was found through applying the ideal gas law to the

total engine volume at 500 psi, which yielded 1.4g.

Operating Temperatures

The expected operating temperatures were derived from a thermal analysis,

contained within the engineering design section, and are expected to be 375C for

the hot end, and 25 C for the cold end.

Cooling Reservoir

The heat transfer coefficient between the water surface and the ambient air

is based on a slight breeze, which would result in a value of h of around 24W/m^2

K.

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Engine Adiabatic Analysis

The model used to analyze the engine is a variable pressure, variable temperature,

and variable volume model. The equation set was developed by Berchowitz in1984 and leads to a system of six simultaneous differential equations as the

solution of the engine.

Nomenclature Used for Adiabatic Sterling Engine Analysis

Symbol Description Units

Tc Temperature of Working Gas within the compression space Kelvin

Tk Temperature of Working Gas within the cooler Kelvin

Th Temperature of Working Gas within the heater Kelvin

Te Temperature of Working Gas within the expansion Kelvin

p Pressure of the Working Gas Pa

Dp Change in Pressure Pa/s

M Total Mass of Working Gas kg

mc Mass of Working Gas within the compression space Kg

mk Mass of Working Gas within the cooler kg

mh Working Gas Mass within the heating kg

me Working Gas Mass within the expansion space kg

Dmc Change in mass of the compression space kg/s

Dmk Change in mass of the cooler kg/s

Dmh Change in mass of the heater kg/s

Dme Change in mass of the expansion space kg/s

gAck Mass flow rate from compression space to cooler kg/s

gAhe Mass flow rate from heater to expansion space kg/s

W Work Done by the engine J

Qk Energy flow rate from cooler to working Gas J

Qh Energy flow rate from heater to working Gas J

DW Change in work done by the engine J/s

DQk Change in Energy flow rate from cooler to working Gas J/s

DQh Change in Energy flow rate from heater to working Gas J/s

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Material Selection

Engine: Below are the material requirements for various portions of the Sterling

engine, and the selected material to meet the requirements.

Hot End

The hot end of the engine needs to withstand 975K, 300 psi internal pressure with

a complex interior geometry, conduct heat effectively, be as absorptive as

possible of thermal radiation, and be as inexpensive as possible. To meet

these requirements, we chose a commercial Aluminum coated in parsons golden

paint.

Cold EndThe cold end of the engine needs to withstand 350K, 300 psi internal pressure,

conduct heat effectively, and be as inexpensive as possible. To meet these

requirements, we chose generic Aluminum Alloy.

Crank Shaft

The crank shaft of the engine needs to withstand 100Kg, loads of approximately

1400 pounds-force, rotate at 250 rpm, and be as inexpensive as possible. To meet

these requirements, we chose 3/8 cast alloy steel.

Rods

The rods of the engine need to withstand 400K, loads of approximately 100

pounds-force and be as inexpensive as possible. To meet these requirements, we

chose 1050 alloy steel.

Bolts

The bolts holding the engine together need to withstand 800K, 1500

pounds- force, be thermally non-conductive, and be as inexpensive as

possible. To meet these requirements, we chose 18-8 Stainless Steel.

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Displacer

The base plate of the displacer piston needs to withstand 400K, 600 pounds-force,

be thermally non-conductive, and be as inexpensive as possible. To meet these

requirements, we chose .125 Lexan. The pin connection the displacer piston to

the crankshaft needs to withstand 400K, 100 kg-force, be thermally non-conductive, and be as inexpensive as possible. To meet these requirements, we

chose .25 1050 alloy steel.

Power Piston

The power piston of the engine needs to withstand 350K, 100 pounds-force, 200

psi, be thermally conductive, and be as inexpensive as possible. To meet these

requirements, we chose generic Aluminum Alloy.

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Reasons to use a Sterling Engine

There are several reasons to use a Sterling Engine:

One reason is that for this kind of engine its almost impossible to explode.

You dont have to produce steam in a high pressure boiler. And inside the

cylinder there are no explosions needed to run the pistons like in an Otto or

Diesel engine. There are no ignitions, no carburetion because you only need

one kind of gas and no valve train because there are no valves. This was a

big advantage to the steam engines in the days when Sterling invented his

engine because it was much less dangerous to work next to a Sterling engine

than to a common steam engine.

Inside the pistons can be used air, helium, nitrogen or hydrogen and you

dont have to refill it because it uses always the same body of gas.

To produce heat you can use whatever you want: fuel, oil, gas, nuclear

power and of course renewable energies like solar, biomass or geothermal

heat.

The external combustion process can be designed as a continuous process,

so the most types of emissions can be reduced.

If heat comes from a renewable energy source they produce no emissions.

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They run very silent and they dont need any air supply. Thats why they are

used a lot in submarines. E.g. in the Royal Swedish Navy.

They can be constructed to run very quiet and practically without any

vibration.

They can run with a small temperature difference, e.g. with the heat of your

hand or from a cup of hot coffee. They can be used as little engines for work

which needs only low power.

They can run for a very long time because the bearings and seals can be

placed at the cool side of the engine they need less lubricant and they

dont have to be checked very often ( longer period between the overhauls).

They are extremely flexible. The engine can run as a CHP (combined heat

and power) because the heat which is produced to run it can easily be

collected. Or in summers they can be used as coolers.

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Analyze from Economic point

As said above the Sterling engine is a kind of external combustion engine,

and it can use a variety of fuels. It can be estimated that combustible gases

are the best material, including gasoline, diesel, propane, sunshine and salad

oil; even cow dung can be run on as fuels.

A cup of coffee cannot become a cup of gasoline, but it can be also used as a

Sterling engine driver. There is a famous experiment that a sterling enginecan easily run on a cup of coffee. The sterling engine is a kind of piston

engine. In the external heating sealed chamber, t he expansion of gases

inside the engine promotes the pistons work. After the expanded gases

cooling down in the air-conditioned room, next process is taking on. As long

as a certain value of the temperature difference exists, a sterling Engine can

be formed.

This experiment shows that only a very small power operation can carry out

a sterling engine, which contributes a lot to energy conservation. This

characteristic especially shows out on economy point. The benefits obtained

fro m the sterling engine are definitely far beyond the costs.

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So once solar is used to produce energy for the sterling engine, the cost

would surely be cut down for quite a lot. As long as there is sunshine, the

sterling engine will run on and on. Of course it costs much to manufacture a

sterling engine, as it requires a high level of the materials and manufacturing

processes. The expansion-side heat exchangers temperature is often veryhigh, so the materials must stand the corrosive consequences of the heat.

Typically these material requirements substantially increase the cost of the

engine. The materials and assembly costs for a high temperature heat

exchanger typically accounts for 40% of the total engine cost.

But once the Sterling engine is made and put into a proper condition, quite a

few costs would be paid for keeping it running.

Some engines cause a lot of pollution, so much is cost for pollution control

and government. On contrast, Sterling engine exhausts cleanly and avoid

this type of matter. Development and utilization of solar will not pollute the

environment, as solar is one of the cleanest energy. While the environmental

pollution is becoming more and more serious today, this characteristic is

extremely valuable. It saves the cost for a lot while making sustainabledevelopment.

At the end of 18th century and the early 19th century, heat engine generally

is steam engine. Its efficiency is very low, only 3% to 5%, that is, over 95%

of the heat is not used. Sterling thermodynamic theory is aiming to improve

the thermal efficiency. Sterling proposed that the Sterling cycle efficiency,

under the ideal condition, may get the infinite enhancement. Certainly itcannot come to 100% due to the physical limitation, however the theory

provide a direction for improving the thermal efficiency. In fact, now the

efficiency of Sterling engine can come up to 80% or even more. So another

part of cost is saved.

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Nowadays, more and more countries have recognized that a society with

sustainable development should be able to meet the needs of the community

without endangering future generations. Therefore, use clean energy as

much as possible instead of the high carbon content of fossil energy is a

principle which should be followed during energy construction. Vigorously

develop new and renewable sources of energy utilization technology will be

an important measure to reduce pollution. Energy problem is a worldwide

one, and it is sooner or later to get into the transition-to-new-energy period.

Applications of the Sterling power

Cars:

In the ages of 1970s and 1980s several automobile companies like General

Motors or Ford were researching about Sterling Engine. This device is good for

a constant power setting, but it is a challenge for the stop and go of the automobile.

A good car can change the power quickly. One possibility to obtain this important

characteristic is design a power control mechanism that will turn up or down the

burner. This is a slow method of changing power levels because is not enough to

accelerate crossing an intersection.

The best solution in spite of these difficulties in automobiles is hybrid electric cars

where Sterling Engine could give enough power to make long trips where could

get burn gasoline or diesel, depending on which fuel was cheaper. The batteriescould give the instant acceleration that drivers are used to. This invention makes

the car silent and clean running.

Submarine:

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Less vibration is good advantage for the propeller in means of torque, nowadays

the propeller is designed considering the pulse of torque As long as the prop is also

the flywheel it must be heavy and robust.

Usually the first failure is the ignition system, in the Sterling the ignition isnecessary at the beginning to start the fire after is not needed. Another hamper is

eliminated without valves. In the following graph it is possible see that the

performance of the Sterling engine increases with altitude because the system is

sealed without reference of ambient air density. As the outside temperature

declines, engine power increases. This compounds the natural ability of the aircraft

to fly faster as air density decreases.

Sterling allow the plane to cruise above the weather rather than trough it thus it is a

safety aspect because there are many accidents because the weather. In addiction,the possibility of the pilot to choose the altitude could benefit the optimize use of

the winds.

There are several reasons for the superior fuel economy. First, the Sterling is a

much more efficient power plant. An internal combustion engine takes in new air

and fuel for each stroke, saving nothing from the previous one. But the Sterling re-

uses the same heat energy on successive strokes; the fuel is only needed to make

up the losses. The second reason is that the fuel is always burned full lean, at the

best air/fuel ratio, while normal aircraft engines actually use gasoline as a coolant.

The Sterling also uses the exhaust from the burner to preheat the incoming

combustion air. Since the Sterling exhaust is cool, it is obvious that less energy is

being thrown away.

Heat and power System:

This device replaces traditional boilers in houses. It is an innovative systemdeveloped to provide central heating, water heating and electricity.

Usually this device is called Micro Combined Heat and Power (CHP) and

produces much less carbon dioxide than other ways of providing heat and power.

In fact, if the level of CHP was increased to the Government's target of 10,000

MW, the UK could be one third of the way to meeting its international

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commitments to reduce carbon dioxide emissions. The company Whisper Gen has

launched to the market the market MkV AC gas fired that consists in four cylinders

with double acting Sterling cycle. It is possible coach heat output from 7.5-12KW

at 220-240V

Benefits:

Savings through the production of own electricity.

Reduce emissions of CO2 and other emissions.

Avoiding peak-load costs when the network is overloaded.

Allows for rapid introduction of new generation capacity.

The performance is over 90% of the fuel energy resulting in a cleaner and more

cost effective alternative to traditional electricity generation. Electricity generated

can be fed back into the electricity grid or used in the home, reducing electricity

costs even further. Invent provides an average household with a saving of about

150 per year. It also reduces carbon dioxide emissions by up to 1.5 tons per year,

a real contribution towards tackling the effects of global warming. Thats 20% less

carbon dioxide per household.

Cryocooler

If It is applied mechanical energy instead of cold and heat sources by means of

external engine, It is possible reach temperatures like 10 K (-263C) in machines

of high technology.

The first Sterling-cycle cryocooler was developed at Philips in the 1950s and

commercialized in such places as liquid nitrogen production plants. This companyis still active in the development and manufacturing Sterling cryocoolers and

cryogenic cooling systems.

A wide variety of smaller size Sterling cryocoolers are commercially available for

tasks such as the cooling of sensors.

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Thermo acoustic refrigeration uses a Sterling cycle in a working gas which is

created by high amplitude sound waves.

Nuclear power

Steam turbines of a nuclear plan can be replaced by Sterling engine thus reduce the

radioactive by-products and be more efficient. Steam plants use liquid sodium as

coolant in breeder reactors, water/sodium exchanger are required, which in some

cases that temperature increase so much this coolant could reacts violently with

water. NASA has developed a Sterling Engine known as Sterling Radioisotope

(SRG) Generator designed to generate electricity in for deep space proves inlasting missions. The heat source is a dry solid nuclear fuel slug and the cold

source is space itself. This device converter produces about four times more

electric power from the plutonium fuel than a radioisotope thermoelectric

generator.

These generators have been extensively tested but have not yet been deployed on

actual missions. Thus each SRG will utilize two Sterling converter units with about

500 watts of thermal power supplied by two GPHS (General Purpose Heat Source)

units and will deliver 100-120 watts of electric power. Each GPHS contains four

iridium-clad Pu-238 fuel pellets, stands 5 cm tall, 10 cm square and weighs 1.44

kg. The hot end of the Sterling converter reaches 650C.

The power output of the generator will be greater than 100 W at the beginning of

life, but the wear out of plutonium decrease the heat source. However control

system allows long life.

Solar Energy

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Placed at the focus of a parabolic mirror a Sterling engine can convert solar energy

to electricity with efficiency better than non-concentrated photovoltaic cells.

In 2005 it is created a 1 kW Sterling generator with a solar concentrator, this was a

herald of the coming of a revolutionary solar, nowadays It generates electricitymuch more efficiently and economically than Photovoltaic (PV) systems whit

technology called concentrated solar power (CPS). Nowadays the company Infina

Applications has development a 3 kW Solar Sterling Product.

Some companies are launching technology using steel, cooper, aluminum and glass

in the same low cost manufacturing techniques used to make consumer products.

The equipment is well characterized with over 25,000 hours of on-sun time.

This technology is the worlds most efficiency for the conversion of solar energy to

grid delivery electricity, roughly twice as efficient of the others alternative solar

technologies.

By a mirror to focus the suns rays on the receiver end of Sterling engine. The

internal side of the receiver then heats hydrogen gas, which expands. The pressure

created by the expanding gas drives a piston, crank shaft, and drive shaft assembly

much like those found in internal combustion engines but without igniting the gas.

The drive shaft is connected to a small electricity generator. This solar

application is called concentration solar power (CSP) and is significant

potential grid for water pumping or electrification.

In California there is a big contract where the electrical output represents from

approximately 1.4 percent to 2.6 percent of Edisons annual sales.

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Next year the Sterling solar dish will be able to be in the market, therefore high

capacity to produce energy with the power of sun helping to reduce emissions of

CO2 gases.

It is possible nowadays dream with CHP plants working with Sterling Engines and

it is expected that this technology will be commercially available within the next

few years.

NASA uses an advanced system to concentrate the sunlight. Waste heat is removed

through a heat exchanger and dissipated by radiator panels to space. The

power and distribution system is based on the closed Brayton cycle. Arecuperative heat exchanger between the turbine discharge and receiver inlet

is used to improve cycle efficiency. Long life is made possible through the use of

non-contacting gas bearings, hermetic sealing of the gas circuit, redundant

electronic components, and ultraviolet/atomic oxygen protective coatings on all

optical surfaces. Radiation degradation is reduced relative to solar photovoltaic

arrays since semi-conducting materials are not used on the large exposed surfaces.

Design Considerations

Assembly and Disassembly

It is planned for the assembly to occur within a factory under decently clean

conditions. Disassembly is not anticipated, as the product is not expected to be

recovered after deployment.

Maintenance of the System

Regular Maintenance

Monitoring of internal working pressure

Lubrication of bearings

Inspection for overheating damage

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Major Maintenance

Major maintenance is not anticipated, as the design life of the engine is only 4

months. It is not anticipated that the package will not be recovered after

deployment, as the low cost of the power system inhibits the feasibility of

reconditioning and re-deploying.

Environmental Impact

There is expected to be little environmental impact from the engine. No exotic

metals, or toxic gases, or reactive components.

Risk Assessment

There are always risks when handling pressurized objects; to mitigate the risk of

explosion a pressure release valve will be installed on all engines.

Project Management

Project Management is perhaps one of the most important aspects of this project.

Without it, this concept of solar Sterling engine will be just a concept and will be

hard pressed to find a place in engineering applications as well as the

commercial and humanitarian sector. The project management includes

accomplishing objectives, meeting deadlines, and reaching milestones.

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Cost Analysis

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Material Type Quantity Rate

Plate Aluminum(Virgin) 1 36`

Tube Aluminum(Virgin) 2 300`

Rod Mild Steel(Bright) 1 30`

Bush Mild Steel(Bright) 1 10`

Flywheel Mild Steel(Bright) 1 30`

Counter Weight Mild Steel(Bright) 1 30`

Fly Wheel Bush Mild Steel(Bright) 1 20`

Base Plate Mild Steel(Bright) 1 5`

Connecting Rod Mild Steel(Bright) 2 10`

Global Rotator Mild Steel(Bright) 2 10`

Connecting Pin Mild Steel(Bright) 1 10`

Allen Screw M5 2 10`

Grub Screw M5 2 10`

Wood Screw M4 8 10`

Needle Bearing 2 50`

Wooden Base Ply Wood 1 100`

Gas Tube Aluminum 2 40`

Fiber Glass Insulation As req 50`

Spirit Lamp 1 50`

Denatured Alcohol 350ml 15`Water Emery 2 10`

Nylon Mount Nylon 1 25`

Misc. Charges + Labour 2000`

TOTAL AMOUNT 3396`


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Process Carried

Oxy Acetylene Welding-Aluminum

Oxy Acetylene Welding-Brass

MIG Welding

Grinding

Drilling

Tapping

Honing

Turning

Facing

Boring

Plating

Reverse engineering

Reverse engineering is taking apart an object to see how it works in order to

duplicate or enhance the object. The practice, taken from older industries, is nowfrequently used on computer hardware and software. Software reverse engineering

involves reversing a program's machine code (the string of 0s and 1s that are sent

to the logic processor) back into the source code that it was written in, using

program language statements.

Software reverse engineering is done to retrieve the source code of a program

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because the source code was lost, to study how the program performs certain

operations, to improve the performance of a program, to fix a bug (correct an error

in the program when the source code is not available), to identify malicious content

in a program such as a virus or to adapt a program written for use with one

microprocessor for use with another. Reverse engineering for the purpose of

copying or duplicating programs may constitute a copyright violation. In some

cases, the licensed use of software specifically prohibits reverse engineering.

Someone doing reverse engineering on software may use several tools to

disassemble a program. One tool is a hexadecimal dumper, which prints or

displays the binary numbers of a program in hexadecimal format (which is easier

to read than a binary format). By knowing the bit patterns that represent the

processor instructions as well as the instruction lengths, the reverse engineer can

identify certain portions of a program to see how they work. Another common tool

is the disassembler. The disassembler reads the binary code and then displays each

executable instruction in text form. A disassembler cannot tell the difference

between an executable instruction and the data used by the program so a debugger

is used, which allows the disassembler to avoid disassembling the data portions of

a program. These tools might be used by a cracker to modify code and gain entry

to a computer system or cause other harm.

Hardware reverse engineering involves taking apart a device to see how it works.

For example, if a processor manufacturer wants to see how a competitor's

processor works, they can purchase a competitor's processor, disassemble it, and

then make a processor similar to it. However, this process is illegal in many

countries. In general, hardware reverse engineering requires a great deal of

expertise and is quite expensive.

Another type of reverse engineering involves producing 3-D images of

manufactured parts when a blueprint is not available in order to remanufacture the

part. To reverse engineer a part, the part is measured by a coordinate measuring

machine (CMM). As it is measured, a 3-D wire frame image is generated and

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displayed on a monitor. After the measuring is complete, the wire frame image is

dimensioned. Any part can be reverse engineered using these methods.

Design Considerations and Future Work

Future work would include patent applications for various components of the

design including the internalization of the crankshaft inside of the engine,

application of a Fresnel lens to power a Sterling, and utilization of a cooling

channel to remove waste heat from the engine. Further work could be done in

further designing the power distribution and conditioning of the engine in

order to expand the concept into domestic energy production. This would

include long term design analysis, as well as a more intricate cooling system.

The need for a more permanent tracking system would increase the overall

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cost of the system, however, is still expected to be extremely competitive with

current solar energy conversions.

If a domestic version is to be expanded upon, then it would justify the refinement

of the internal geometry to focus more on efficiency instead of cost.

Optimization of internal geometry based on internal aero-dynamic flow

consideration would be preformed which would be based on a CFD run with heat

transfer as well as aerodynamic considerations.

Lessons Learned

A wealth of knowledge was generated from this design & fabrication project that

could help future design teams in their endeavors. Through the design process, a

methodology for analyzing and modeling of a Sterling engine was established.

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Figures Through SW2010

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Figure 1Shaft1static-spindle-shaft

Figure 2Master cylinder

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Figure 3Pillar

Figure 4Crank part

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Figure 5Pillar Assay

Figure 6Photo Shopped Sterling Engine

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economic needs at present time, but also in the future.

The Sterling engine is an interesting device like it is showed in this document with

various applications and high development. Its advantages are really beneficial for

the environment because it is possible produce electricity with the power of sun

with high efficiency (theatrically like the Carnot Cycle). It is a huge advantage to

the economy because is possible to burn the cheapest fuel and it is working instead

of the more expensive one. And this engine is comfortable for the people because

is quiet and not noisy like an internal combustion engine.

The real renewable energy is the solar application for this device because

the other ways to produce the heat source are burning something. It is

possible to decrease the emissions of CO2 or other toxic gases but not

eliminate completely this problem for the earth and therefore for humans.

This application could be one of the different ways to solve the problem of

greenhouse gas emissions and to continue and also to develop our comfort.

In all applications that was showed in this presentation the performance the

devices are better, obviously increase the efficiency is good

Depend of which kind of fuel is getting burn in process. The Sterling Engine is a

machine of external combustion thus if it is burned fuel the emissions of CO2 is

not solved. It is showed that the performance is better but in the

point of view of environment the real problem continues existing.

Find a heat source to make it works, this is the case of biomass fuels in

connection with a Sterling engine are concentrated on transferring the heat

from the combustion of the fuel into the working gas and in the same way the

solar application.

Because, as companies look increasingly to alternative power units, it is entirely

possible that the Sterling engine will find its own niche in the marketplace, perhaps

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as part of a hybrid power plant, or through further development and optimization.

No high-tech materials are needed. This competes with solar cells.

Taking one with another, Sterling engine bring a tremendous revolution to human

being. We think there is also a lot of potential in this area because modern

industrialization should be sustained by regenerate power system. It is not a dead

end but a new start.

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Bibliography

In order to accomplish the current project, the following web pages have been

consulted. The authors of the project would like to thank the following for theiraccuracy, clarity and conciseness.

http://en.wikipedia.org/wiki/Stirling_engine

http://www.kockums.se

http://www.grc.nasa.gov/WWW/tmsb/index.html

http://www.infiniacorp.com/main.htm

http://www.stirlingenergy.com

http://www.whispergen.com/index.cfm http://www.sunpower.com/index.php

http://www.sesusa.org/index.html

http://news.soliclima.com

http://www.nrel.gov/csp

http://www.bekkoame.ne.jp/%7Ekhirata/english/others.htm

http://www.cec.uchile.cl/~roroman/

www.blog.steamshift.com www.techfreep.com

www.sensi.org

www.energytech.at

www.Sterlingenergy.com

www.Stirlingengine.com

www.logicsys.com.tw/wrkbas.htm.

www.bbc.co.uk/dna/h2g2/A9042707

www.ent.ohiou.edu/~me321/chapter4th.info/Chapter3.html

www.ent.ohiou.edu/~urieli/stirling/me422.html

final report engineering 2011

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