improving thermal efficiency of diesel engine by using ... · work [3].the energy lost can be...
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International Journal of Mechanical Engineering and Technology (IJMET) Volume 8, Issue 7, July 2017, pp. 834–845, Article ID: IJMET_08_07_092
Available online at http://www.iaeme.com/IJMET/issues.asp?JType=IJMET&VType=8&IType=7
ISSN Print: 0976-6340 and ISSN Online: 0976-6359
© IAEME Publication Scopus Indexed
IMPROVING THERMAL EFFICIENCY OF
DIESEL ENGINE BY USING CERAMIC
COATING ON CYLINDER LINER AND PISTON
HEAD
M. Soundar
Assistant Professor, Mechanical Engineering,
SRM University Ramapuram campus, Chennai, India
P. Anand
Associate Professor, Mechanical Engineering,
Veltech Dr RR & Dr SR University, Avadi, Chennai, India
V. Ramesh
Assistant Professor, Mechanical Engineering,
Veltech Dr RR & Dr SR University, Avadi, Chennai, India
ABSTRACT
In general only 40% of power produced in the engine is converted into useful work
other than that 30% of heat escape through exhaust and 30% of heat is which cannot
be converted into useful work is removed as waste heat with the help of cooling system.
To convert this waste heat into useful work the cylinder liners and piston head is coated
with ceramic coating. This will lead to reduction in heat transfer through the engine,
involving an increased efficiency. Change in combustion process due to insulation also
affects emissions. Higher gas temperature should reduce the concentration of
incomplete combustion products at the expense of an increase in nitrogen oxides (NOx).
However a decrease in carbon monoxide (CO) unburned hydrocarbons (HC) is
observed. Here we are going to analyze the uncoated cylinder with coated one using
ANSYS and in experimental method using thermal image camera. The result depicted
that the ceramic coated cylinder is more efficient than uncoated one.
Key words: Zirconium Oxide, Thermal Imaging Camera, Cylinder Liner, Piston Head.
Cite this Article: M. Soundar, P. Anand and V. Ramesh, Improving Thermal Efficiency
of Diesel Engine by Using Ceramic Coating On Cylinder Liner and Piston Head,
International Journal of Mechanical Engineering and Technology, 8(7), 2017, pp. 834–
845.
http://www.iaeme.com/IJMET/issues.asp?JType=IJMET&VType=8&IType=7
Improving Thermal Efficiency of Diesel Engine by Using Ceramic Coating On Cylinder Liner and
Piston Head
http://www.iaeme.com/IJMET/index.asp 835 [email protected]
INTRODUCTION
In automobile sector, the main objective is to improve the performance by reducing the fuel
consumption of an engine and increase the power. The diesel engine has the highest thermal
efficiency of any standard combustion engine due to its very high compression ratio. Diesel
engines are more efficient than gasoline (petrol) engines of the same power rating resulting in
lower fuel consumption. The increased fuel economy of diesel engine over the petrol engine
produces less carbon dioxide per unit distance. A design and development of a high power with
low heat rejection, direct injection automotive diesel engines requires a thorough knowledge of
in cylinder combustion and heat transfer characteristic. These information and analysis will be
helpful in designing an energy efficient engine, by coating with ceramics over the cylinder liner
and piston head. Thermal barrier coatings are highly advanced material systems applied to
metallic surfaces, such as gas turbine aero-engine and diesel engine parts, operating at elevated
temperatures. These coatings serve to insulate metallic components from large and prolonged
heat loads by utilizing thermally insulating materials which can sustain an appreciable
temperature difference between the load bearing alloys and the coating surface. In doing so,
these coatings can allow for higher operating temperatures while limiting the thermal exposure
of structural components, extending part life by reducing oxidation and thermal fatigue.
In fact, in conjunction with active film cooling, Thermal barrier coatings permit flame
temperatures higher than the melting point of the metal airfoil in some turbine applications.
Modern Thermal barrier coatings are required to not only limit heat transfer through the coating
but to also protect engine components from oxidation and hot corrosion. No single coating
composition appears able to satisfy these multifunctional requirements. As a result, a “coating
system” has evolved. Research in the last 20 years has led to a preferred coating system
consisting of three separate layers such as metal substrate, bond coat and ceramic coating to
achieve long term effectiveness in the high temperature, oxidative and corrosive use
environment for which they are intended to function. The application of Thermal barrier
coatings on the diesel engine piston head reduces the heat loss to the engine cooling-jacket
through the surfaces exposed to the heat transfer such as cylinder head, liner, piston crown and
piston rings. It is important to calculate the piston temperature distribution in order to control
the thermal stresses and deformations within acceptable levels. The temperature distribution
enables the designer to optimize the thermal aspects of the piston design at lower cost, before
the first prototype is constructed. As much as 60% of the total engine mechanical power lost is
generated by piston ring assembly.
The metal substrate is typically a high temperature aluminum alloy that is either in single
crystal or polycrystalline form. The metallic bond coat is an alloy typically with the composition
of Nickel, Cobalt, Chromium, Aluminum. The bond coat creates a bond between the ceramic
coat and substrate. The third coat is the ceramic topcoat, Zirconia (ZrO2), Mullite (3Al2O3-
2SiO2), Alumina (Al2O3) which is desirable for having very low conductivity while remaining
stable at nominal operating temperatures typically seen in applications.
This layer creates the largest thermal gradient of the thermal barrier coating. In industry,
thermal barrier coatings are produced in a number of ways.
• Electron Beam Physical Vapor Deposition (EBPVD).
• Air Plasma Spray (APS).
• Electrostatic Spray Assisted Vapour Deposition (ESAVD).
• Direct Vapor Deposition.
Diesel engine piston made of Cast iron is taken for this study and ceramic material having
low thermal conductivity is preferred as the coating material on the piston head or crown.
M. Soundar, P. Anand and V. Ramesh
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PROBLEM FORMULATION
A cursory look at the internal combustion engine heat balance indicates that the input energy is
divided into roughly three equal parts: energy converted to useful work, energy transferred to
coolant and energy lost to exhaust as a waste heat. The 20% of energy is lost due to heat, 30%
of energy is transferred to coolant and remaining 50% of energy is only converted to useful
work [3].The energy lost can be recovered by ceramic coating (Crown of the piston, side of the
cylinder liner, cylinder head )
Figure 1 Ceramic Coating
MATERIALS
ZIRCONIA (ZrO2)
Zirconium dioxide (ZrO2), sometimes known as zirconia (not to be confused with zircon), is a
white crystalline oxide of zirconium. Its most naturally occurring form, with
a monoclinic crystalline structure, is the mineral baddeleyite. A dopant stabilized cubic
structured zirconia, cubic zirconia, is synthesized in various colors for use as a gemstone and
a diamond stimulant. Zirconia can be found in three crystal structure as it can be seen in Fig.
4.1. These are monolithic (m), tetragonal (t) and cubic (c) structures. Monolithic structure is
stable between room temperature and 1170 °C while it turns to tetragonal structure above 1170
°C. Tetragonal structure is stable up to 2379 °C and above this temperature, the structure turns
to cubic structure.
Figure 2 Three Crystal Structure For ZrO2
Improving Thermal Efficiency of Diesel Engine by Using Ceramic Coating On Cylinder Liner and
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Usually cracks and fractures are observed during changing phases because of 8% volume
difference while transition to tetragonal structure from monolithic structure. To avoid this and
make zirconia stable in cubic structure at room temperature, alkaline earth elements such as
CaO (calcium oxide), MgO (magnesia), Y2O3 (yttria) and oxides of rare elements are added to
zirconia. Zirconia based ceramic materials stabilized with yttria have better properties
comparing with Zirconia based ceramic materials which are stabilized by magnesia and calcium
oxide (Yaşar, 1997; Geçkinli, 1992). Mechanical properties of cubic structure zirconia are
weak. Transition from tetragonal zirconia to monolithic zirconia occurs at lower temperatures
between 850-1000 0C and this transition has some characteristics similar to martensitic
transition characteristics which are observed in tempered steels. In practice, partially stabilized
cubic zirconia (PSZ) which contains monolithic and tetragonal phases as sediments, is preferred
owing to its improved mechanical properties and importance of martensitic transition. Partially
stabilized zirconia has been commercially categorized since early 70s. Table 4.1 contains
partially stabilized zirconia types and their properties.
Structural properties of these materials are;
• Zt35: Contains 20% (t) phase in cubic matrix. Particle dimensions are about 60-70 μm.
• ZN40: Contains 40-50% (t) phase.
• ZN50: Particle dimensions are about 60-70 μm and a thin film (m) phase lays on the borders of
particles.
Table 1 Structural Properties
SPRAY COATING
Spray coating is the modern of coating. Here the solution is sprayed by using the nozzle, which
produce high pressure and atomizes the liquid or solution and gives the accurate coating over
the required surface.
TYPES OF SPRAY COATING
• Flame spray coatings
• Powder flame spray coatings
• Wire flame spray coatings
• Plasma spray coating
THERMAL IMAGE CAMERA
A Thermal Imaging Camera (colloquially known as a TIC) is a type of thermo graphic
camera used in firefighting. By rendering infrared radiation as visible light, such cameras
allow firefighters to see areas of heat through smoke, darkness, or heat-permeable barriers.
M. Soundar, P. Anand and V. Ramesh
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Thermal imaging cameras are typically handheld, but may be helmet-mounted. They are
constructed using heat- and water-resistant housings, and ruggedized to withstand the hazards
of fire ground operations. While they are expensive pieces of equipment, their popularity and
adoption by firefighters in the United States is increasing markedly due to the increased
availability of government equipment grants following the September 11 attacks in 2001.
Thermal imaging cameras pick up body heat, and they are normally used in cases where people
are trapped where rescuers cannot find them.
A thermal imaging camera consists of five components: an optic system, detector, amplifier,
signal processing, and display. Fire-service specific thermal imaging cameras incorporate these
components in a heat-resistant, ruggedized, and waterproof housing. These parts work together
to render infrared radiation, such as that given off by warm objects or flames, into a visible
light representation in real time. The camera display shows infrared output differentials, so two
objects with the same temperature will appear to be the same "color". Many thermal imaging
cameras use grayscale to represent normal temperature objects, but highlight dangerously hot
surfaces in different colors.
INFRARED THERMOMETER
An infrared thermometer is a thermometer which infers temperature from a portion of
the thermal radiation sometimes called blackbody radiation emitted by the object being
measured. They are sometimes called laser thermometers if a laser is used to help aim the
thermometer, or non-contact thermometers or temperature guns, to describe the device's ability
to measure temperature from a distance. By knowing the amount of infrared energy emitted by
the object and its emissivity, the object's temperature can often be determined. Infrared
thermometers are a subset of devices known as "thermal radiation thermometers". Sometimes,
especially near ambient temperatures, false readings will be obtained indicating incorrect
temperature. This is most often due to other thermal radiation reflected from the object being
measured, but having its source elsewhere, like a hotter wall or other object nearby - even the
person holding the thermometer can be an error source in some cases. It can also be due to an
incorrect emissivity on the emissivity control or a combination of the two possibilities.
The most basic design consists of a lens to focus the infrared thermal radiation on to
a detector, which converts the radiant power to an electrical signal that can be displayed in units
of temperature after being compensated for ambient temperature. This configuration facilitates
temperature measurement from a distance without contact with the object to be measured. As
such, the infrared thermometer is useful for measuring temperature under circumstances where
thermocouples or other probe type sensors cannot be used or do not produce accurate data for
a variety of reasons. Some typical circumstances are where the object to be measured is moving;
where the object is surrounded by an electromagnetic field, as in induction heating; where the
object is contained in a vacuum or other controlled atmosphere; or in applications where a fast
response is required, an accurate surface temperature is desired or the object temperature is
above the recommended use point for contact sensors, or contact with a sensor would mar the
object or the sensor, or introduce a significant temperature gradient on the object's surface.
Infrared thermometers can be used to serve a wide variety of temperature monitoring
functions.
A few examples provided to this article include:
• Detecting clouds for remote telescope operation.
• Checking mechanical equipment or electrical circuit breaker boxes or outlets for hot spots.
• Checking heater or oven temperature, for calibration and control purposes.
Improving Thermal Efficiency of Diesel Engine by Using Ceramic Coating On Cylinder Liner and
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• Detecting hot spots / performing diagnostics in electrical circuit board manufacturing.
• Checking for hot spots in fire fighting situations.
• Monitoring materials in process of heating and cooling, for research and development or
manufacturing quality control situations
There are many varieties of infrared temperature sensing devices available today, including
configurations designed for flexible and portable handheld use, as well many designed for
mounting in a fixed position to serve a dedicated purpose for long periods. Specifications of
portable handheld sensors available to the home user will include ratings of temperature
accuracy (usually with measurement uncertainty of ±2 °C/±4 °F) and other parameters.
Figure 3 Infrared Thermometer Figure 4 Diesel Engine
The distance-to-spot ratio (D: S) is the ratio of the distance to the object and the diameter
of the temperature measurement area. For instance if the D:S ratio is 12:1, measurement of an
object 12 inches (30 cm) away will average the temperature over a 1-inch-diameter (25 mm)
area. The sensor may have an adjustable emissivity setting, which can be set to measure the
temperature of reflective (shiny) and non-reflective surfaces. A non-adjustable thermometer
sometimes can be used to measure the temperature of a shiny surface by applying a non-shiny
paint or tape to the surface, if the allowed measurement error is acceptable. The most common
infrared thermometers are the:
• Spot Infrared Thermometer or Infrared Pyrometer, which measures the temperature at a
spot on a surface (actually a relatively small area determined by the D:S ratio).
METHODS
ENGINE SPECIFICATION
We collect the data’s related to the diesel engine from the THIAGARAJAR COLLEGE OF
ENGINEERING, Madurai.
Table 2 Engine Specification
M. Soundar, P. Anand and V. Ramesh
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The Kirloskar, Vertical, Four stroke Diesel engine specifications shown. The design of this
engine in Pro-E is shown.
Figure 5 Dimensions of The Cylinder Head And Liner Figure 6 Piston Analysis
The analysis of the Cylinder without Ceramic Coating in ANSYS is shown below.
Figure 7 Piston Analysis Before Coating Figure 8 Piston Analysis After Coating
In the Fig 7 The temperature of 1200°C is given between Piston head and Cylinder liner it
is found that without Ceramic coating, the outer surface of the cylinder experiences a
temperature of 100°C. Here more heat loss takes place. We aimed to reduce the heat loss and
make it as a useful work by doing ceramic coating over the cylinder liner and piston head.
In the Fig 8 The temperature of 1200°C is given between Piston head and Cylinder liner it
is found that with 35 times spray (1mm) Ceramic coating, The outer surface of the cylinder
experiences a temperature of 10°C. Here less heat loss takes place. Here 90°C of heat is made
as useful work by doing ceramic coating over the cylinder liner and piston head.
METHODS
PRACTICAL METHODS
STEPS
• Selection of Cast iron bar
• Preparation of Zirconium oxide solution
• Coating of Cast iron bar
• Thermal Analysis
SELECTION OF CAST IRON BAR
Cast iron bar of 10×5×2 cm is used for coating with Zirconium oxide. This selected Cast iron
bar is heated and examined under thermal image camera.
Improving Thermal Efficiency of Diesel Engine by Using Ceramic Coating On Cylinder Liner and
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Figure 9 Cast Iron Bar Figure 10 ZIR Conium Oxide Powder
PREPARATION OF ZIRCONIUM OXIDE SOLUTION
Zirconium Oxide is in powder form. It was bought from the chemical shop. It is made into
liquid form with some other mixtures to coat over the cast iron plate.
Composition of Zirconia
• Zirconium Oxide(ZrO2) - 97%
Impurities are
• Silicate(SiO2) - 0.25%
• Titanium(TiO2) - 0.16%
• Iron(Fe2O3) - 0.07%
SOLUTION PREPARATION
• 5gm of Zirconium Oxide
• 1gm of Zirconium Nitrate
• 150ml of Water
• 50ml of Ethanol
• 2ml of Tri ethanol amine
Mixing the above components at the mentioned quantities with the PH 10.
COATING
The solution must be mixed with the above mentioned ratio only. Because this ratio will give
the perfect mixture and it will perfectly settle over the cast iron plate. The mixture is spayed
over the cast iron bar. Before spraying the cast iron is heated at 250 °C. This temperature is
noted by using the infrared thermometer. Because only at this temperature the solution will
settle over the plate permanently. The solution is sprayed using powder flame spray coating.
The coating can be given with different sprays. Here we choose 15 sprays, 25 sprays, 35 sprays.
We can analyze the cast iron bar with these different sprays and the heat loss can be found.
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Figure 11 Temperature Noted Using Infrared Thermometer
Figure 12 Uncoated Bar Figure 13 Sprays Coated Bar
Figure 14 Sprays Coated Bar Figure 15 Sprays Coated Bar
Figure 16 after Coating
THERMAL ANALYSIS
• Here the Cast iron bar is placed over the furnace and start heating the bar.
• The Solution prepared is kept ready for spraying over the bar.
• When the temperature of 250°C obtain the spray must done over the bar.
Improving Thermal Efficiency of Diesel Engine by Using Ceramic Coating On Cylinder Liner and
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• There must be 3 bars chosen for the three different sprays 15, 25 and 35 sprays.
• After spraying the bar is allowed to cool at room temperature so that the solution set over the
bar permanently.
• Then the bar with coating of 15, 25 and 35 sprays and un coated bars are placed over the hot
plate.
• The hot plate is maintained at 150°C for 15mins.
• Then the Cast iron bars are placed over hot plate.
• Now the temperature distributions are noted by using the thermal image camera and the
temperature variations are noted down for all bars.
RESULT AND DISCUSSION
IMAGE CAPTURE BY USING FLIR E60 THERMAL IMAGE CAMERA
Figure 17 Thermal Image Capture for Uncoated and 15 Times Spray Bar
Figure 18 Thermal Image Capture For 25 And 35 Times Spray Bar
Initially an uncoated & 15 times spray cast iron bar is placed on the hot plate, then a hot
plate heated up to 150°C. Maintained a heat for 15 mins. Then take a capture by using FLIR
E60 thermal image camera. The fig 7.1 shown the temperature difference from uncoated bar to
15 times spray cast iron bar.
From the Thermal image camera it is noted that
• Uncoated cast iron bar – 91.0°C
• 15 times Spray Cast iron bar – 86.3°C
• 25 times Spray Cast iron bar – 74.8°C
• 35 times Spray Cast iron bar – 69.6°C
M. Soundar, P. Anand and V. Ramesh
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CONCLUSION
Cast iron has wide range of applications in various field due to its property, one of its special
application is in automobile field and engine parts. Due to higher thermal property the cast iron
is used in engines also. They are used to manufacture cylinder liners and piston head. There is
always high temperature of about 1200°C. There was heavy heat loss takes place at the outer
surface of the engine. This heat loss should be reduced and change into the useful work by some
criteria. We analyzes the cylinder of the Kirloskar, Vertical, Four stroke Diesel engine, using
ANSYS. First we analyze the cylinder without coating here we gave 1200°C, we found that at
the outer surface of the cylinder there is 100°C. But when analyzing the cylinder with 1mm
coating of zirconium oxide at 1200°C the result shows that the outer surface of the cylinder
only 10°C. There is 90°C of heat is made into useful work.
In the experimental analysis using thermal image camera, the Zirconium Oxide is coated
over the cast iron bar and analyzed. We are Heating the bar of 150°C, It is noted that 35 times
spray bar (69.6°C) was more efficient than 25(74.8°C) and 15(86.3°C) times spray and
uncoated (91°C). But when the spray times exceed more than 35, then the thickness of coating
increased over 1mm. So, the coating must be at 35 sprays.
REFERENCES
[1] Kamo R. and Bryzik W., 1978, Adiabaticturbo-compound engine performance prediction,
SAE International, Paper No. 780068.
[2] Kamo R. and Bryzik W., 1979, Ceramics in heat engines, SAE International, Paper No.
790645.
[3] Kamo R. and Bryzik W., 1981, Cummins- Tradocom adiabatic turbo-compounded engine
program, SAE International, Paper No. 810070.
[4] Bryzik W. and Kamo R., 1983, TACOM/Cummins adiabatic engine program, SAE
International, Paper No. 830314.
[5] Kamo R. and Bryzik W., 1984, Cummins/TACOM advanced adiabatic engine, SAE
International, Paper No. 840428.
[6] Sekar R.R. and Kamo R., 1984, Advanced adiabatic diesel engine for passenger cars, SAE
International, Paper No. 840434.
[7] Kamo R., Woods M.E. and Bryzik W., 1989, “Thin thermal barrier coating for engines”,
United States Patent, Patent No. US4852542.
[8] Winkler M.F., Parker D.W. and Bonar J.A., 1992, Thermal barrier coatings for diesel
engines: ten years of experience, SAE International, Paper No. 922438
[9] Winkler M.F. and Parker D.W., 1993, The role of diesel ceramic coatings in reducing 315
A review of thermal barrier coating, International Journal of Automotive Engineering Vol.
3, Number 1, March 2013 automotive emissions and improving combustion efficiency, SAE
International, Paper No. 930158.
[10] Kamo R., Bryzik W., Reid M. and Woods M., 1997, Coatings for improving engine
performance, SAE International, Paper No. 970204.
[11] Uzun A., CevikI. and Akcil M., 1999, Effects of thermal barrier coating on a turbo charged
diesel engine performance, Surface and Coatings Technology, 116-119, 505–507.
[12] Murthy P.V.K, Krishna M.V.S., Raju A., Prasad C.M. and Srinivasulu N.V., 2010,
Performance evaluation of low heat rejection diesel engine with pure diesel, International
Journal of Applied Engineering Research, 1 (3), 428-451.
[13] ThringR.H, 1986, Low Heat Rejection Engines, SAE International, Paper No.860314.
Improving Thermal Efficiency of Diesel Engine by Using Ceramic Coating On Cylinder Liner and
Piston Head
http://www.iaeme.com/IJMET/index.asp 845 [email protected]
[14] Buyukkaya E., Engin T. and Cerit M., 2006, Effects of thermal barrier coating on gas
emissions and performance of a LHR engine with different injection timings and valve
adjustments, Energy Conversion and Management, 47, 1298-1310.
[15] Alkidas A.C., 1989, Performance and emissions achievements with an un-cooled heavy
duty single cylindered diesel engine, SAE International, Paper No.890144.
[16] Assanis D., Wiese K., Schwarz E. and BryzikW, 1991, The effect of ceramic coatings on
diesel engine performance and exhaust, SAE International, Paper No. 910460.
[17] Sun X., Wang W.G., Lyons D.W., and Gao X., 1993, Experimental analysis and
performance improvement of single cylinder direct injection turbocharged low heat
rejection engine, SAE International, Paper No.930989.
[18] Jaichandar S. and Tamilporai P., 2003, Low heat rejection engines - an overview, SAE
International, Paper No. 2003-01-0405.
[19] Ramu P. and Saravanan C.G., 2009, Effect of ZrO2-Al2O3 and SiC coating on diesel engine
to study the combustion and emission characteristics, SAE International, Paper No. 2009-
01-1435.
[20] P.Sivakumar, V.Nagaraju, Subhankarghosh, Rajeevraushan and G.S.S.Anuroop
Experimental Investigation of 4--Stroke Single Cylinder Diesel Engine Using Alternative
Fuels. International Journal of Mechanical Engineering and Technology, 8(5), 2017, pp.
409-419.
[21] S. Ramu, R. Srinivasan, S. Somasundaram and Tariku Achamyeleh. Design of Exhaust
Silencer Muffler for Transmission Losses with the Performance of a Four Stroke Diesel
Engine with and Without Muffler Section. International Journal of Mechanical Engineering
and Technology, 8(1), 2017, pp. 139–145.
[22] Wade W.R., Havstad P.H., Ounsted E.J, Trinkerand F.H. and Garwin I.J., 1984, Fuel
economy opportunities with an un-cooled DI diesel engine, SAE International, Paper
No.841286.