Alexandria Engineering Journal (2015) 54, 295–302
HO ST E D BY
Alexandria University
Alexandria Engineering Journal
www.elsevier.com/locate/aejwww.sciencedirect.com
ORIGINAL ARTICLE
Influence of injection timing and compression ratioon performance, emission and combustioncharacteristics of Annona methyl ester operateddiesel engine
Abbreviations: BP, brake power; SFC, specific fuel consumption;
BSFC, brake specific fuel consumption; BTE, brake thermal efficiency;
CI, compression ignition; CR, compression ratio; IT, injection timing;
CA, crank angle; CO, carbon monoxide; HC, hydrocarbon; NOx,
oxides of nitrogen; HRR, heat release rate; CHRR, cumulative heat
release rate; CV, calorific value; DI, direct injection; NDIR, non-
dispersive infrared; ppm, parts per million; AME, Annona methyl ester* Corresponding author.
E-mail address: [email protected] (R. Senthil).
Peer review under responsibility of Faculty of Engineering, Alexandria
University.
http://dx.doi.org/10.1016/j.aej.2015.05.0081110-0168 ª 2015 Faculty of Engineering, Alexandria University. Production and hosting by Elsevier B.V.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Senthil Ramalingam *, Silambarasan Rajendran, Ravichandiran Nattan
Department of Mechanical Engineering, University College of Engineering Villupuram, Tamil Nadu, India
Received 28 January 2015; revised 29 April 2015; accepted 12 May 2015Available online 6 July 2015
KEYWORDS
Annona methyl esters;
Injection timing;
Compression ratio;
Performance;
Emission;
Combustion
Abstract This study targets at finding the effects of the engine design parameters viz. compression
ratio (CR) and fuel injection timing (IT) jointly on the performance with regard to specific fuel con-
sumption (SFC), brake thermal efficiency (BTHE) and emissions of CO, HC, Smoke and NOx with
Annona methyl ester (A20) as fuel. Thus A20 can be effectively used in a diesel engine without any
modification. Compression ratio of 19.5 along with injection timing of 30�bTDC (before top deadcentre) will give better performance and lower emission which is very close to diesel. Comparison of
performance and emission was done for different values of compression ratio along with injection
timing to find best possible combination for operating engine with A20. It is found that the com-
bined increase of compression ratio and injection timing increases the BTE and reduces SFC while
having lower emissions. Diesel (20%) saved, will greatly meet the demand of fuel in railways.ª 2015 Faculty of Engineering, Alexandria University. Production and hosting by Elsevier B.V. This is anopen access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
1. Introduction
Annona squamosa is a member of the family of Custard apple
trees called Annonaceae and a species of the genus Annonaknown mostly for its edible fruits Annona. It is commonlyfound in India and Cultivated in Thailand and it originates
from the West Indies and South America. A. squamosa pro-duces fruits that are usually called sugar apple or custard applein English, sitafal in Marathi, sharifa in Hindi, sitaphalam in
Tamil and Telugu in India and corossolier and cailleux, pom-miercannelle in French. It is mainly grown in gardens for itsfruits and ornamental value. It is considered as beneficial for
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296 R. Senthil et al.
cardiac disease, diabetes, hyperthyroidism and cancer. Theroot is considered as a drastic purgative.
In this paper we reported that A20 gives better performance
and reduction emissions are achieved. These studies were car-ried out in different types of engines (stationary/mobile; singlecylinder/multi cylinder; constant speed/variable speed) with
bio-diesel prepared from different oil origins. To sum up theresults of these studies, a cumulative study taking some orall the parameters at a time in one type of engine is still miss-
ing. To fill this gap, the study was done with an objective offinding the optimum engine design parameters viz. compres-sion ratio and injection timing, for better performance of dieselblended with bio-diesel (A20) obtained from Annona oil. The
aim was to establish the modifications required in small, con-stant speed, direct injection diesel engines used extensivelyfor agricultural applications so that these can be made to
run on diesel and bio-diesel blend with better performanceand at the same time improve the emissions.
As per the US department of Energy [1], the world’s oil sup-
ply will reach its maximum production and midpoint of deple-tion sometime around the year 2020. Future projectionsindicate that the only feasible option is the production of syn-
thetic fuels derived from non-petroleum sources [2]. For substi-tuting the petroleum fuels used in internal combustion engines,fuels of bio-origin provide a feasible solution to the twin crisesof ‘fossil fuel depletion’ and ‘environmental degradation’. For
diesel engines, a significant research effort has been directedtowards using vegetable oils and their derivatives as fuels.Non-edible vegetable oils in their natural form called as
straight vegetable oils (SVO), methyl or ethyl esters knownas treated vegetable oils, and esterified vegetable oils referredto as bio-diesel fall in the category of biofuels. Bio-diesel is
considered a promising alternative fuel for use in diesel engi-nes, boilers and other combustion equipments. These arebio-degradable, can be mixed with diesel in any ratio and are
free from sulphur. Although bio-diesel has many advantagesover diesel fuel, there are several problems that need to beaddressed such as its lower calorific value, higher flash point,higher viscosity, poor cold flow properties, poor oxidative sta-
bility and sometimes its comparatively higher emission ofnitrogen oxides [3]. Bio-diesel obtained from some feedstocksmight produce slightly more oxides of nitrogen (1–6%), which
is an ozone depressor, than those of fossil origin fuels but canbe managed with the utilization of blended fuel of bio-dieseland high speed diesel fuel [4]. It is found that the lower concen-
trations of bio-diesel blends improve the thermal efficiency.Reduction in emission and brake specific fuel consumption isalso observed while using B10 [5]. The operating parametersmust be optimized in light of the specific fuel properties.
Effect of injection parameters [6–12] such as spray [13], injec-tion timing and compression ratio [14–18] has been studiedin detail at many places. Most of the research studies con-
cluded that in the existing design of engine and parametersat which engines are operating, a 20% blend of bio-diesel withdiesel works well [4]. Many researchers indicated the need of
research in the areas of engine modifications so as to suit tohigher blends without severe drop in performance so that therenewability advantages along with emission reduction can
be harnessed to a greater extent. Effect of variations in theseparameters has been studied taking one or more parametersat a time [19].
2. Transesterification of vegetable oils
Transesterification is the process of using an alcohol (e.g.methanol or ethanol) in the presence of catalyst such as
sodium hydroxide (NaOH) or potassium hydroxide (KOH),which chemically breaks the molecule of the raw oil intomethyl or ethyl esters with glycerol as a by-product, which
reduces the high viscosity of oils. This method also reducesthe molecular weight of the oil to 1/3 of its original value,reduces the viscosity, and increases the volatility and cetanenumber to levels comparable to diesel fuel. Conversion not
greatly affects the gross heat of combustion. Transesterificationis the change of the trivalent glycerin molecules against 3 mole-cules of monovalent alcohol methanol. Each is a monoester. In
the most vegetable oils, fatty acids with 16 and 18 carbonatoms predominate.
3. Experimental setup
The schematic diagram of the engine test rig used is shown inFig. 1. The engine is fully equipped with measurements of all
operating parameters. In the study, compression ignitionengine was run with AME (A20) at different compressionratios (16.5, 17.5, 18.5, 19.5 and 20.5) and injection timings
(24, 27, 30 and 33 bTDC) to evaluate the performance, emis-sions and combustion characteristics at 50% load. The resultswere compared against the diesel fuel results as well as for dif-ferent combinations of compression ratio and injection timing.
The properties of Annona methyl ester and diesel are shown inTable 1.
Figure 1 Experimental setup.
Table 1 Fuel properties of AME and diesel.
Properties Diesel AME
Cetane no 48 52
Specific gravity 0.83 0.8802
Viscosity @ 40 �C 3.9 5.18Calorific value (MJ/kg) 43 36.4
Density (g/cm3) 0.830 0.880
Flash point (�C) 56 76Fire point (�C) 64 92Oxygen content (%) – 11
Influence of injection timing and compression ratio 297
3.1. Specifications of the apparatus
In the test rig there are several instruments/equipments thathave been used for the purpose of the experiment. Brief spec-ifications of the instruments are given below.
3.1.1. Diesel engine
Manufacturer
Kirloskar oil engines limitedType of engine
Vertical, 4-Stroke Single cylinderMaximum power
8 HPMax brake power
6.02 kWSpeed
1800 rpmCompression ratio
17.5:1Bore and stroke
87.5 · 110 (mm)
Injection pressure
200 bar3.1.2. Smoke meter
Smoke meter is used to determine the smoke density of theengine exhaust. The AVL 437 smoke meter has been designed
for simple one man operation from alongside a vehicle foreither free acceleration or steady state test procedures.Control is via a compact and rugged handset with a digital
L.C.D. Any out of range parameters are automatically flaggedto the operator. The brief specifications of the smoke meter aregiven below:
Type
AVL 437 smoke meterMake
AVL India Pvt. LtdMeasuring range
0 to 100HSUTable 2 Experiment uncertainties.
Parameters Systematic errors (±)
Speed 1 ± rpm
Load ±0.1 N
3.1.3. Exhaust gas analyzer
Time ±0.1 s
Brake power ±0.15 kW
Manufacturer
SMS Autoline Equipments private limitedTemperature ±1�
Type
Crypton 290 five gas analyzerPressure ±1 bar
NOX ±10 ppm
CO ±0.03%
CO2 ±0.03%
HC ±12 ppm
Smoke ±1HSU
3.2. Testing procedure
Engine was started, warmed up at low idle, long enough toestablish the recommended oil pressure, and was checked for
any fuel, oil leaks. The engine was run on no-load conditionand speed was adjusted to 1800 rpm by adjusting fuel injectionpump. Engine was run to gain uniform speed, after which it
was gradually loaded. Experiments were conducted at differenttorque levels (0, 8, 16, 24 and 32 Nm). The engine was run for10 min and data were collected during last 3 min. For 20%
biodiesel, performance tests were carried out at five differentcompression ratios and four different injection timings.
The exhaust gas is the sample from exhaust pipeline and
passed through a four gas analyzer for measurement of carbonmonoxide, carbon dioxide, unburnt hydrocarbon, and oxidesof nitrogen present in exhaust gases. A smoke meter is usedfor measurement of smoke capacity. The measurement range
and accuracy of the exhaust gas analyzer and smoke meter isshown in Table 2.
4. Results and discussion
Test engine was run with different fuels and time for 10 cc fuelconsumption was calculated.
4.1. Effect of injection timing on performance, emission and
combustion characteristics
4.1.1. Specific fuel consumption (SFC)
Fig. 2 shows the variations of specific fuel consumption for
injection timing and for A20 blend when compared to the neatdiesel fuel. 30�bTDC of injection timing gives lowest SFC ascompared to all other Injection Timings and neat diesel fuel.The specific fuel consumption of the A20 blend at the injection
timing of 30�bTDC is 0.346 kg/kW h whereas for diesel it is0.385 kg/kW h. This may be due to higher viscosity and lowvolatility which causes better utilization of oxygen leading to
better combustion.
4.1.2. Brake thermal efficiency (BTE)
Fig. 3 shows the variations of brake thermal efficiency for
injection timing and for A20 blend when compared to the neatdiesel fuel. 30�bTDC gives highest BTE than all other injectiontimings when compared to that of neat diesel fuel. The brake
thermal efficiency of the A20 blend at the injection timing of30�bTDC is 21.95% and almost equal to that of neat dieselfuel (23.35%). This may be due to combination of low volatil-
ity and mass flow rate which indicates inputs to the engine,which in case of A20, are more compared to neat diesel.
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
24 27 30 33
SFC
(kg/
kW-h
)
Injec�on TIming ( 0 bTDC)
Diesel
A20
Figure 2 Injection timing vs. Specific fuel consumption.
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
24 27 30 33
CO (%
)
Injec�on Timing ( 0 bTDC)
Diesel A20
Figure 4 Injection timing vs. Carbon monoxide.
0
100
200
300
400
500
600
24 27 30 33
NO
X(PP
M)
Injec�on Timing ( 0 bTDC)
Diesel A20
Figure 5 Injection timing vs. Oxide of nitrogen.
420
440
460
480
500
520
540
24 27 30 33
HC (P
PM)
Diesel
A20
298 R. Senthil et al.
4.1.3. Carbon monoxide (CO)
Fig. 4 shows the variations of Carbon monoxide for injectiontiming and for A20 blend when compared to the neat dieselfuel. 30�bTDC gives low CO emission than all other injectiontimings when compared to that of neat diesel fuel. The brakethermal efficiency of the A20 blend at the injection timing of30�bTDC is 0.08 ppm whereas for diesel it is 0.095 ppm. Thismay be due to oxygen concentration and cetane number.Since AME fuel contains oxygen it acts as a lesser combustionpromoter inside the cylinder.
4.1.4. Oxides of nitrogen (NOx)
Fig. 5 shows oxides of nitrogen for different compressionratios and for A20 blend when compared to the neat diesel
fuel. 30�bTDC gives low NOx emission than all other injectiontimings and compared to that of neat diesel fuel there is a slightincrease in NOx emissions. The NOx emission of the A20 blendat the injection timing of 30�bTDC is 340 ppm whereas for die-sel it is 320 ppm. This may be due to the presence in biodieselof oxygen, which leads to complete combustion of biodieselthan diesel. As a result, maximum temperature inside cylinder
is more in case of biodiesel than diesel.
4.1.5. Hydrocarbon (HC)
Fig. 6 shows the variations of hydrocarbon emission for injec-
tion timing and for A20 blend when compared to that of neatdiesel fuel. 30�bTDC gives low HC emission than all otherinjection timings when compared to that of neat diesel fuel.
0
5
10
15
20
25
24 27 30 33
BTE
(%)
Injec�on Timing ( 0 bTDC)
Diesel
A20
Figure 3 Injection timing vs. Brake thermal efficiency.
Injec�on Timing (0 bTDC)
Figure 6 Injection timing vs. Hydrocarbon emission.
The HC emission of the A20 blend at the injection timing of30�bTDC is 460 ppm whereas for diesel it is 470 ppm. Thismay be due to viscosity and surface tension that affect penetra-tion rate and droplet size of fuel, which in turn affect mixing offuel and air. Cetane number of fuel also plays a vital role in
ignition process.
4.2. Smoke
Fig. 7 shows the variations of smoke emission for injectiontiming and for A20 blend when compared to that of neat dieselfuel. 30�bTDC gives low smoke emission than all other
0
10
20
30
40
50
60
70
80
90
100
24 27 30 33
Smok
e (H
SU)
Injec�on Timing ( 0 bTDC)
Diesel
A20
Figure 7 Injection timing vs. Smoke.
-10
0
10
20
30
40
50
60
70
80
90
180 280 380 480 580
PRES
SURE
(bar
)
CRANK ANGLE (deg)
DIESEL A20
Figure 8 Crank angle vs. Pressure.
-60
-40
-20
0
20
40
60
80
100
180 280 380 480 580HRR
(J/d
eg C
A)
CRANK ANGLE (deg)
DIESEL A20
Figure 9 Crank angle vs. Heat release rate.
0
50
100
150
200
250
300
350
400
180 280 380 480 580CU
MM
. HRR
(J/d
eg C
A)
CRANK ANGLE (deg)
DIESEL
A20
Figure 10 Crank angle vs. Cumulative heat release rate.
Influence of injection timing and compression ratio 299
injection timings when compared to that of neat diesel fuel.The smoke emission of the A20 blend at the injection timingof 30�bTDC is 73HSU whereas for diesel it is 77HSU. Thisis due to that biodiesel contains excess oxygen, locally overthe rich region which decreases the formation of crucial smokerestricted by the favourable effect of the oxygen content bio-
diesel. This is due to greater accumulation of the fuel duringignition delay period and leads to the fuel injected earlier intothe combustion chamber.
4.2.1. Cylinder pressure
Fig. 8 shows variations of cylinder pressure with respect tocrank angle for different injection timings and for A20 when
compared to that of neat diesel fuel. The peak pressuredecreases by 4.5% for A20 blend at 24�bTDC, increases by5.7% for A20 blend at 30�bTDC and increases by 1.4% forA20 blend at 33�bTDC when compared to A20 blend at27�bTDC.
4.2.2. Heat release rate (HRR)
Fig. 9 shows variations of heat release rate with respect tocrank angle for different compression ratios and for A20 whencompared to that of neat diesel fuel. The maximum HRR
increases by 6.8% for A20 blend at 24�bTDC, decreases by2.03% for A20 blend at 30�bTDC and decreases by 0.66%for A20 blend at 33�bTDC when compared to A20 blend at27�bTDC. At normal engine conditions the minimum delay
occurs with start of injection 10–15�bTDC. The increase inthe delay time with earlier or later injection timing occurs
because of the air temperature and pressure during delayperiod.
4.2.3. Cumulative heat release rate
Fig. 10 shows variations of cumulative heat release rate withrespect to crank angle for different compression ratios andfor A20 when compared to that of neat diesel fuel. The maxi-
mum Cumulative HRR decreases by 13.8% for A20 blend at24�bTDC, decreases by 20.23% for A20 blend at 30�bTDCand decreases by 19.04% for A20 blend at 33�bTDC whencompared to A20 blend at 27�bTDC.
4.3. Effect of compression ratio on performance, emission andcombustion characteristics
4.3.1. Specific fuel consumption (SFC)
Fig. 11 shows variations of specific fuel consumption for dif-
ferent compression ratios and for A20 blend when comparedto that of neat diesel fuel. 19.5:1 of compression ratio giveslowest SFC as compared to all other compression ratios and
neat diesel fuel. The specific fuel consumption of the A20 blendat the compression ratio of 19.5:1 is 0.30 kg/kW h whereas fordiesel it is 0.32 kg/kW h. This is due to the fact that increase in
compression ratio reduces BSFC due to reduction in dilutionof charge by residual gases, which results in better BTE andlower BSFC. However increase in BSFC is observed withlower compression ratio due to slow combustion pressure
because of more charge diameter and lower compression pres-sure and temperature.
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
16.5 17.5 18.5 19.5 20.5
SFC
(k
g/k
W-h
)
Compression RatioCompression Ratio
Diesel
A20
Figure 11 Compression Ratio vs. Specific fuel consumption.
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
16.5 17.5 18.5 19.5 20.5
CO
(%
)
Compression RatioCompression Ratio
Diesel
A20
Figure 13 Compression Ratio vs. Carbon monoxide.
300 R. Senthil et al.
4.3.2. Brake thermal efficiency (BTE)
Fig. 12 shows variations of brake thermal efficiency for differ-ent compression ratios and for A20 blend when compared tothat of neat diesel fuel. 19.5:1 of compression ratio gives high-
est BTE as compared to all other compression ratios and neatdiesel fuel. The BTE of the A20 blend at the compression ratioof 19.5:1 is 30.67% and it is almost to that of neat diesel fuel
(31.41%). This is due to the fact that increase in compressionratio ensures more complete combustion due to injection offuel in higher temperature and pressure compressed air, betterair–fuel mixing and faster evaporation, whereas, reduction in
compression ratio resulted in lower BTE due to lower com-pression pressure and temperature, slow combustion process,and more dilution by residual gas.
4.3.3. Carbon monoxide (CO)
Fig. 13 shows variations of carbon monoxide for differentcompression ratios and for A20 blend when compared to that
of neat diesel fuel. 19.5:1 of compression ratio gives lowest COemission as compared to all other compression ratios and theneat diesel fuel. The CO emission of the A20 blend at the com-
pression ratio of 19.5:1 is 0.05 ppm whereas for diesel it is0.06 ppm. This may be due to better combustion, and less dilu-tion of charge by residual gases accelerates the carbon oxida-
tion to form carbon dioxide. At lower compression ratio, thecarbon monoxide emissions are increased due to more dilutionof fresh air with residual gases, lower compression temperature
and poor mixing of fuel and air.
0
5
10
15
20
25
30
35
16.5 17.5 18.5 19.5 20.5
BT
E (
%)
Compression RatioCompression Ratio
Diesel
A20
Figure 12 Compression Ratio vs. Brake thermal efficiency.
4.3.4. Oxides of nitrogen (NOx)
Fig. 14 shows variations of oxides of nitrogen for differentcompression ratios and for A20 blend when compared to thatof neat diesel fuel. 19.5:1 of compression ratio gives lowest
NOx as compared to all other compression ratio and the slightincrease in NOx emission as compared to that of neat dieselfuel. The NOx emission of the A20 blend at the compression
ratio of 19.5:1 is 515 ppm whereas for diesel it is 510 ppm.This may be due to the fact that increase in compression ratioincreases the combustion pressure and temperature which
accelerates the oxidation of nitrogen to form oxides of nitro-gen. At lower compression ratio, the combustion takes placeduring expansion stroke which results in lower combustiontemperature and pressure which leads to lower NOx emission.
4.3.5. Hydrocarbon (HC)
Fig. 15 shows variations of hydrocarbon emission for different
compression ratios and for A20 blend when compared to thatof neat diesel fuel. 19.5:1 of compression ratio gives lowest HCemission as compared to all other compression ratios and theneat diesel fuel. The HC emission of the A20 blend at the com-
pression ratio of 19.5:1 is 26 ppm whereas for diesel it is29 ppm. This may be due to the increase in the air temperatureat the end of compression stroke, enhancement in combustion
temperature and reduction in charge dilution which leads tobetter combustion and reduction in hydrocarbon emissions.Increase in hydrocarbon emission is observed with reduction
in compression ratio which is due to slow combustion process.
0
100
200
300
400
500
600
700
800
16.5 17.5 18.5 19.5 20.5
NO
X(P
PM
)
Compression RatioCompression Ratio
Diesel
A20
Figure 14 Compression Ratio vs. Oxides of nitrogen.
0
5
10
15
20
25
30
16.5 17.5 18.5 19.5 20.5
HC
(P
PM
)
CCompression n Ratio
Diesel
A20
Figure 15 Compression Ratio vs. Hydrocarbon emission.
0
10
20
30
40
50
60
70
80
90
180
200
220
240
260
280
300
320
340
360
380
400
420
440
460
480
500
520
540
Diesel
A20
Crank angle (deg)
HR
R (
J/d
eg
CA
)
Figure 18 Crank angle vs. Heat release rate.
Influence of injection timing and compression ratio 301
4.4. Smoke
Fig. 16 shows variations of smoke emission for different com-pression ratios and for A20 blend when compared to that of
neat diesel fuel. 19.5:1 of compression ratio gives lowest smokeemission as compared to all other compression ratios and theneat diesel fuel. The smoke emission of the A20 blend at the
compression ratio of 19.5:1 is 15.7HSU whereas for diesel itis 16.5HSU. This is due to biodiesel that consists of two oxy-gen atoms which leads to the oxidation of soot and thereby
reducing the soot emissions.
4.4.1. Cylinder pressure
Fig. 17 shows variations of cylinder pressure with respect to
crank angle for different compression ratios and for A20 when
0
2
4
6
8
10
12
14
16
18
20
16.5 17.5 18.5 19.5 20.5
Smo
ke
CCompression n Ratio
Diesel
A20
Figure 16 Compression Ratio vs. Smoke.
0
10
20
30
40
50
60
70
180
200
220
240
260
280
300
320
340
360
380
400
420
440
460
480
500
520
540
diesel
A20
Crank angle (deg)
Cyl
ind
er
Pre
ssur
e (
bar
)
Figure 17 Crank angle vs. Pressure.
compared to that of neat diesel fuel. The cylinder pressure for
A20 blend is almost equal to that of neat diesel fuel. This is dueto longer ignition delay and lower cetane number of the blend.The cylinder pressure of the neat diesel fuel is higher than that
of A20 blend at lower compression ratio. This is due to fasterand complete combustion inside the combustion chamber. Themaximum rate of increase in pressure is increasing with com-pression ratio for different blends.
4.4.2. Heat release rate
Fig. 18 shows the variations of heat release rate with respect to
crank angle for different compression ratios and for A20 blendwhen compared to that of neat diesel fuel. The HRR is ana-lyzed based on the changes in crank angle variation of thecylinder. The HRR is increased with lower compression ratio
and slightly decreased at higher compression ratio. TheHRR of neat diesel is higher than that of A20 blend due toits reduced viscosity and better spray formation.
4.4.3. Cumulative heat release rate
Fig. 19 shows the variations of heat release rate with respect tocrank angle for different compression ratios and for A20 blend
0
50
100
150
200
250
300
350
400
450
500
180
200
220
240
260
280
300
320
340
360
380
400
420
440
460
480
500
520
540
A20
Diesel
Crank angle (deg)
CH
RR
(J/
de
g C
A)
Figure 19 Crank angle vs. Cumulative heat release rate.
302 R. Senthil et al.
when compared to that of neat diesel fuel. The maximumCumulative HRR decreases by 12.20% for A20 blend at16.5:1, decreases by 6.84% for A20 blend at 18.5:1, decreases
by 15.50% for A20 blend at 19.5:1 and decreases by 11.39%for A20 blend at 20.5:1 when compared to A20 blend at17.5:1. This may be due to injection of more quantity of fuel
during larger delay period and slow combustion.
5. Conclusion
Injection timing of 30�bTDC, along with compression ratio of19.5 gives better performance, combustion and lower emis-sions when compared with standard Injection timing of
27�bTDC and compression ratio of 17.5. For all tested values,A20 provides best results in terms of BTE, higher heat releaserate, and lower emissions of HC, CO and NOx. Hence A20 can
be effectively used as an alternative biodiesel with Injectiontiming of 30�bTDC along with compression ratio of 19.5 intested engine. Even though only 20% of Annona methyl esteris added with 80% pure diesel, will meet to a certain extent the
shortage of availability of pure diesel. Annona is available withlower cost when compared to diesel in present scenario. HenceAME will be economical also for diesel trains.
References
[1] M.A.R.S. Al-Baghdadi, Effect of compression ratio.
Equivalence ratio and engine speed on the performance and
emission characteristics of a spark ignition engine using
hydrogen as a fuel, Renew. Energy 29 (2004) 2245–2260.
[2] R. Anandm, G.R. Kannan, S. Nagarajan, S. Velmathi,
Performance emission and combustion characteristics of a
diesel engine fueled with biodiesel produced from waste
cooking oil, SAE 2010-01-0478, 2010.
[3] A.K. Babu, G. Devaradjane, Vegetable oils and their derivatives
as fuels for CI engines, SAE 2003-01-0767, 2003.
[4] M. Balat, H. Balat, Progress in biodiesel processing, Appl.
Energy 87 (2010) 1815–1835.
[5] A. Demirbas, Progress and recent trends in biodiesel fuels,
Energy Convers. Manage. 50 (2009) 14–34.
[6] Dennis Y.C. Leung, Wu Xuan, M.K.H. Leung, A review on
biodiesel production using catalyzed transesterification, Appl.
Energy 87 (2010) 1083–1095.
[7] Hak-Joo Kim, Bo-Seung Kang, Min-Ju Kim, Young Moo Park,
Deog-Keun Kim, Kwan-Young Lee, Transesterification of
vegetable oil to biodiesel using heterogeneous base catalyst,
Catal. Today 93 (2004) 315–320.
[8] Y.V. Hanumantha Rao, Voleti Ram Sudheer, Experimental
investigations on Annona biodiesel and additive in diesel engine,
Indian J. Sci. Technol. 2 (4) (2009).
[9] S. Jindal, B.P. Nandwana, N.S. Rathore, V. Vashistha,
Experimental investigation of the effect of compression ratio
and injection pressure in a direct injection diesel engine running
on Annona methyl ester, Appl. Therm. Eng. 30 (2010) 442–448.
[10] H. Jon, Van Gerpen, Charles L. Peterson, Carroll E. Goering,
Biodiesel: an alternative fuel for compression ignition engines,
Am. Soc. Agric. Biol. Eng. 31 (2007) 1–22.
[11] B. Kegl, Numerical analysis of injection characteristics using
biodiesel fuel, Fuel 85 (2006) 2377–2387.
[12] J. Kjarstad, F. Johnsson, Resources and future supply of oil,
Energy Policy 37 (2009) 441–464.
[13] C. Mohanty, A. Jaiswal, V.S. Meda, P. Behera, S. Murugan, An
experimental investigation on the combustion, performance and
emissions of a diesel engine using vegetable oil–diesel fuel
blends, SAE 2011-01-1187, 2011.
[14] A. Parlak, H. Yasar, B. Sahin, Performance and exhaust
emission characteristics of a lower compression ratio LHR
Diesel engine, Energy Convers. Manage. 44 (2003) 163–175.
[15] H. Raheman, S.V. Ghadge, Performance of diesel engine with
biodiesel at varying compression ratio and ignition timing, Fuel
87 (12) (2008) 2659–2666.
[16] R.V. Shahi, Energy markets and technologies in India, keynote
address in global energy dialogue (Hanover, Germany) 25 April,
2011.
[17] H. Watanabe, T. Tahara, M. Tamanouchi, J. Iida, Study of the
effects on exhaust emissions in direct injection diesel engines:
effect of fuel injection system, distillation properties and cetane
number, JSAE Rev. 19 (1998) 21–26.
[18] K. Wijesinghe, P.D. Rukshan, The influence of water injection
on the thermal efficiency & specific fuel consumption of a ci
engine, Fisita World Automotive Congress, Barcelona, 2004
(February).
[19] S. Ueki, A. Miura, Effect of difference of high pressure fuel
injection systems on exhaust emissions from HDDI diesel
engine, JSAE Rev. 20 (1999) 555–561.
http://refhub.elsevier.com/S1110-0168(15)00080-0/h0005http://refhub.elsevier.com/S1110-0168(15)00080-0/h0005http://refhub.elsevier.com/S1110-0168(15)00080-0/h0005http://refhub.elsevier.com/S1110-0168(15)00080-0/h0005http://refhub.elsevier.com/S1110-0168(15)00080-0/h0020http://refhub.elsevier.com/S1110-0168(15)00080-0/h0020http://refhub.elsevier.com/S1110-0168(15)00080-0/h0025http://refhub.elsevier.com/S1110-0168(15)00080-0/h0025http://refhub.elsevier.com/S1110-0168(15)00080-0/h0030http://refhub.elsevier.com/S1110-0168(15)00080-0/h0030http://refhub.elsevier.com/S1110-0168(15)00080-0/h0030http://refhub.elsevier.com/S1110-0168(15)00080-0/h0035http://refhub.elsevier.com/S1110-0168(15)00080-0/h0035http://refhub.elsevier.com/S1110-0168(15)00080-0/h0035http://refhub.elsevier.com/S1110-0168(15)00080-0/h0035http://refhub.elsevier.com/S1110-0168(15)00080-0/h0040http://refhub.elsevier.com/S1110-0168(15)00080-0/h0040http://refhub.elsevier.com/S1110-0168(15)00080-0/h0040http://refhub.elsevier.com/S1110-0168(15)00080-0/h0045http://refhub.elsevier.com/S1110-0168(15)00080-0/h0045http://refhub.elsevier.com/S1110-0168(15)00080-0/h0045http://refhub.elsevier.com/S1110-0168(15)00080-0/h0045http://refhub.elsevier.com/S1110-0168(15)00080-0/h0050http://refhub.elsevier.com/S1110-0168(15)00080-0/h0050http://refhub.elsevier.com/S1110-0168(15)00080-0/h0050http://refhub.elsevier.com/S1110-0168(15)00080-0/h0055http://refhub.elsevier.com/S1110-0168(15)00080-0/h0055http://refhub.elsevier.com/S1110-0168(15)00080-0/h0060http://refhub.elsevier.com/S1110-0168(15)00080-0/h0060http://refhub.elsevier.com/S1110-0168(15)00080-0/h0070http://refhub.elsevier.com/S1110-0168(15)00080-0/h0070http://refhub.elsevier.com/S1110-0168(15)00080-0/h0070http://refhub.elsevier.com/S1110-0168(15)00080-0/h0075http://refhub.elsevier.com/S1110-0168(15)00080-0/h0075http://refhub.elsevier.com/S1110-0168(15)00080-0/h0075http://refhub.elsevier.com/S1110-0168(15)00080-0/h0085http://refhub.elsevier.com/S1110-0168(15)00080-0/h0085http://refhub.elsevier.com/S1110-0168(15)00080-0/h0085http://refhub.elsevier.com/S1110-0168(15)00080-0/h0085http://refhub.elsevier.com/S1110-0168(15)00080-0/h0095http://refhub.elsevier.com/S1110-0168(15)00080-0/h0095http://refhub.elsevier.com/S1110-0168(15)00080-0/h0095
Influence of injection timing and compression ratio on performance, emission and combustion characteristics of Annona methyl ester operated diesel engine1 Introduction2 Transesterification of vegetable oils3 Experimental setup3.1 Specifications of the apparatus3.1.1 Diesel engine3.1.2 Smoke meter3.1.3 Exhaust gas analyzer
3.2 Testing procedure
4 Results and discussion4.1 Effect of injection timing on performance, emission and combustion characteristics4.1.1 Specific fuel consumption (SFC)4.1.2 Brake thermal efficiency (BTE)4.1.3 Carbon monoxide (CO)4.1.4 Oxides of nitrogen (NOx)4.1.5 Hydrocarbon (HC)
4.2 Smoke4.2.1 Cylinder pressure4.2.2 Heat release rate (HRR)4.2.3 Cumulative heat release rate
4.3 Effect of compression ratio on performance, emission and combustion characteristics4.3.1 Specific fuel consumption (SFC)4.3.2 Brake thermal efficiency (BTE)4.3.3 Carbon monoxide (CO)4.3.4 Oxides of nitrogen (NOx)4.3.5 Hydrocarbon (HC)
4.4 Smoke4.4.1 Cylinder pressure4.4.2 Heat release rate4.4.3 Cumulative heat release rate
5 ConclusionReferences
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