Experimental Investigations and Operating Characterisitics of ...

Experimental Investigations and Operating

Characterisitics of Diesel Engine using Biodiesel 1T.S. Mohanraj,

2V.S. Barathwaj,

3M.S. Marshal Andru and

4S.S. Aravindh Venkatesh

1 School of Mechanical Engineering, SASTRA University.

[email protected] 2School of Mechanical Engineering, SASTRA University.



[email protected]

Abstract Biodiesel is a fuel that is made from natural elements such as plants,

vegetables, and reusable materials. This type of fuel is better for the

atmosphere because, unlike other fuels, it does not give off harmful chemicals

which can influence the environment negatively. The popularity of biodiesel

is consistently increasing as people search out alternative energy resources.

Biodiesel is prepared by the process involving chemical reactions,

transesterification and esterification.This involves vegetable or animal fats

and oils being reacted with short-chain alcohols typically methanol

or ethanol). The alcohols used should be of low molecular weight, ethanol

being one of the most used for its low cost. However, greater conversions into

biodiesel can be reached using methanol. Although the transesterification

reaction can be catalyzed by either acids or bases the most common means of

production is base-catalyzed transesterification. This path has lower reaction

times and catalyst cost than those posed by acid catalysis. However, alkaline

catalysis has the disadvantage of its high sensitivity to both water and

free fatty acids present in the oils.The oil content from cottonseed oilis 18-26 %

and it contains long chain fatty acid. Cotton seed oil is rich in palmitic acid

(22-26%), oleic acid (15-20%), linoleic acid (49-58%) and 10% mixture of other

acid. The FFA present in the raw cotton seed oil is 3.7%. After

transesterification, it is reduced to 1.9%. Similarly, the corresponding value of

viscosity also is reduced from 34 Cst to 11.1 Cst.With the recent developments

in the fuel injection system and more sophisticated components to meet

International Journal of Pure and Applied MathematicsVolume 114 No. 11 2017, 231-240ISSN: 1311-8080 (printed version); ISSN: 1314-3395 (on-line version)url: http://www.ijpam.euSpecial Issue ijpam.eu

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emission norms, a good variety of fuels can be successfully used in

Compression Ignition (CI) engines.Cotton seedoil can be easily blended with

diesel in three different blends B10, B20 and B30. Initially the properties of

cotton seed oil like calorific value, density, viscosity, %FFA, iodine value, and

saponification value were identified and compared with diesel properties. A

single cylinder, water cooled, direct injection CI engine at a constant engine

speed of 1500 rpm was used for testing at various load conditions. The

combustion and emission performance of the engine was obtained and

compared with that of diesel. The effect of injection pressure on the engine

performance was observed by varying the fuel injection pressure from 195 bar

to 215 bar in steps of 5 bar. Since the results are optimum for 205 bar for

performance as well as emission characteristics.

Key words:Cotton seed oil, biodiesel, optimum injection pressure,

performance characteristics.

International Journal of Pure and Applied Mathematics Special Issue

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1. Introduction

The rapid depletion of petroleum fuels and their ever increasing costs have led

to an intensive search for alternative fuels.The role of the biodiesel industry is

not to replace petroleum diesel, but to help create a balanced energy policy with

the most benefit to any country. Biodiesel refers to a vegetable oil - or animal

fat-based diesel fuel consisting of long-chain alkyl (methyl, ethyl, or propyl)

esters. Biodiesel is typically made by chemically reacting lipids(e.g., vegetable

oil, soybean oil, [ animal fat (tallow)) with an alcohol producing fatty acid

esters.

Biodiesel is made through a chemical processcalled transesterification whereby

the glycerin is separated from the fat or vegetable oil. The process leaves behind

two products -- methyl esters (the chemical name for biodiesel) and glycerin (a

valuable byproduct usually sold to be used in soaps and other products).. Diesel

fuel can also be replaced by biodiesel made from vegetable oils.

The properties of vegetable oils are widely varying due to the physical and

chemical changes during handling, stabilization, storage and extraction

process[2]

. The oxidative reaction during storage necessitates the initial

evaluation of the physical and chemical composition of the oil. The oil obtained

was treated with stabilizers and stored in leak proof containers. The

transesterification procedure required was identified based on the FFA content

of the oil[3-5]

. Many researchers [6-7]

have investigated the use of vegetable oils

and highlighted the influence of the following parameters in biodiesel

production. The level of free fatty acids, impurities, water content, ash content,

acid value, iodine value, saponification value, peroxide value, flash point and

kinematic viscosity of the feedstock were determined.[8-10]

and the right method

of biodiesel production and the kind of pre treatment required were identified.

Higher conversion rate was achieved by increasing the temperature and KOH

concentration during transesterification and the duration of the process does not

have any significant effect [11-13]

. The important properties of cotton seed oil

obtained were presented in Table 1.

Table 1: Properties of cotton seed oil

2. Experimental Setup

A stationary 4-Stroke, Direct Injection Diesel Engine (Model USHA )was used

S.no Parameter Diesel Cotton seed oil

1 Density 830 kg/m3 875 kg/m

3

2 Kinematic Viscosity 2.54 mm2/s 3.95 mm

2/s

3 Sp. Gravity 0.83 0.870

4 Calorific value 44300 kJ/kg 39206.5kJ/kg

5 Flash point (oC) 51 172

6 Fire point (oC) 56 180


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for the experimental work. The performance and emission curves were obtained

for different loads and at various injection pressures. The engine specifications

were presented in Table –2.

Table 2: Engine specifications

Figure 1: Experimental setup

The main performance parameters like BSFC and Brake thermal Efficiency

were evaluated. The exhaust gas emissions from the engine were measured by

using exhaust gas analyzer. The engine load was varied using mechanical

loading (Brake Dynamometer). The brake fuel consumption was measured by

using a fuel flow meter. The schematic diagram of experimental setup is shown

in Figure 1.

3. Test Procedure

The engine performance test was conducted with B10, B20 and B30 blends of

cotton seed oil at different load conditions. Similarly the injection pressure are

varied at 195 bar, 200 bar, 205 bar, 210 bar and 215 bar and the optimum

performance characteristics are obtained at 205 bar only. The tests were

conducted at a constant speed of 1500 rpm. The engine was initially allowed to

run at no load condition for ten minutes, for each proportion of the blend before

Engine Single cylinder Diesel Engine

Make USHA stationary Diesel Engine

Working cycle Four stroke, Diesel Engine

Power 3.73 kW

Bore x Stroke 100mm x 110mm

Cooling system Water cooling

Loading setup Brake dynamometer


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applying the load. The loads were gradually increased in steps of 25 % upto

100% at constant speed of 1500 rpm. The same procedure was repeated for

different Injection pressures for all fuel blends. The exhaust gases are measured

by using exhaust gas analyzer from the tail pipe of the engine. The amount of

CO, CO2, HC, O2, and NOx was measured by an exhaust gas analyzer.

4. Results & Discussions

A. Performance Analysis

From performance analysis the result obtained, from 195 bar to 215 bar in steps

of 5 bar, the optimum performance characterisitcs are obtained at 205 bar. B30

blend has lower SFC value at increased loads at 205 bar whereas B10 and B20

have SFC values greater than B30 blend. The higher injection pressure

improves the atomization of biodiesel which leads to better combustion

resulting better mixing of fuel with air and decreases the fuel consumption.

Figure 2: Variation of SFC @ 205 bar

Figure 3: Variation ofɳ BTE @ 205 bar


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From the performance curves there is significant increase in the brake thermal

efficiency for all blends at 205 bar. Maximum brake thermal efficiency of

29.28% was obtained for maximum load at 205 bar injection pressure with B30

blend.

B. Emission Analysis

Figure 4: HydroCarbon emission @ 205 Bar

From emission data, B10 has the lowest hydrocarbon emissions at higher loads

at 205 bar whereasB20 and B30 has increased HC concentration particularly at

higher loads. This is mainly due to the oxygenated biofuel.

Figure 5: Carbon Monoxide Emission @ 205 Bar

The increased volume percentage of cotton seed oil increases the CO %

particularly at lower loads. At higher loads the percentage CO formation has

lowered significantly for all blends. From the emission curve, B30 blend shows

higher CO emissions whereas B10 blend decreases slightly with the

corresponding decrease in B20 from 0.19 % to 0.08 %.


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Figure 6: Carbon dioxide emission @ 205 bar

The percentage carbon dioxide emission was maximum for B20 blend at 205

bar, whereas B10 and B30 blend have carbon dioxide emissions greater than

diesel. The variations in CO2 % with load seem similar for diesel and B 10.

Figure 7: NOx emission @ 205 bar

The NOx formation was high for B20 blend at 205 bar, whereas B10 and diesel

has lower NOx formation compared to the other blends for which the NOx

formation increases significantly with increased loads.

5. Conclusion

The performance and emission characteristics of a direct injection diesel engine

fueled with cotton seed oil and its blend have been investigated. The

experimental results confirm that the BSTE, SFC and exhaust emissions are


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favour for cotton seed oil blend with increase in injection pressures with most

optimum result at 205 bar.The brake specific thermal efficiency of the cotton

seed oil was highest for B30 when compared to other blends and it was found to

be29.28% at 205 bar injection pressure. This may be due to better combustion,

and increase in the energy content of the cotton seed oil. The SFC value is lower

for the blend B30 at 205 bar injection pressure with increasing loads when

compared to other blends. So we can find that the performance characterisitics

of B30 blend is better when compared to other blends and diesel at 205 bar

injection pressures. The hydrocarbon emission is lowest for B10 blend operated

at maximum load at the given injection pressure. The CO emission of the cotton

seed oil is very less for B10 and it is decreased with load at the given injection

pressure. The CO2 emission showsalmost similar trend for all blends and diesel

at the given injection pressure.At lower loads, the emission of oxides of

nitrogen (NOx) is almost same for all blends but with increasing loads we find

that B20 and B30 is lessat the given injection pressure. The combustion

characteristics shows similar trend for all blends with varying injection

pressures but the emission characteristics shows significant changes with

changes in the blending ratios. Based on the results the performance and

emission values are well within the acceptable range for cotton seed oil and it

can be used in diesel engine without any major modification in the engine.

References

[1] Gui M.M., Lee K.T., Bhatia S., Feasibility of Edible vs. Non-Edible oil vs. Waste Edible oil as Biodiesel Feedstock, Energy 32 (2008), 1646-1653.

[2] Mohanraj T., Murugu Mohan Kumar K., Performance and Emission Characteristics of an Agricultural Diesel Engine using Biodiesel Fuel, International Journal of Engineering 1(4) (2011), 11-17.

[3] Goering C.E., SchwAB A.W., Daugherty M.J., Pryde E.H., Heakin A.J, Fuel Properties of Eleven Vegetable Oils, Transactions of the ASAE 25(6) (1982), 1472-1477.

[4] Karim G.A., Amoozegar, Determination of Performance of Dual Fuels Engine with Addition of Various Liquid Fuels to the Intake Charge, SAE, (1983).

[5] Mohanraj T., Murugu Mohan Kumar K., Operating Characteristics of a Variable Compression Ratio Engine using Esterified Tamanu Oil: International Journal of Green Energy 9(5) (2012), 954-963.

[6] Murugesan A., Umarani C., Chinnusamy T.R., Krishnan M., Subramanian R, Production and Analysis of Bio-Diesel from Non-Edible Oils-A Review, Renewable and Sustainable Energy Reviews 13 (2009), 825-834.


238

[7] Saravanan S., Nagarajan G., Lakshmi Narayana Rao G., Sampath S., Combustion Characteristics of a Stationary Diesel Engine Fuelled with a Blend of Crude Rice Bran oil Methyl Ester and Diesel, Energy 35 (2010), 94–100.

[8] Szybist J., Song J., Alam M., Boehman A, Biodiesel Combustion, Emissions, and Emission Control, Fuel Processing Technology 88 (2007), 679-691.

[9] SrinivasaRao K., Ramakrishna A., Sundara Siva Rao B.S.K, Experimental Studies on the Characteristics of Diesel Engine with Chicken Fat Methyl Ester, International Journal of Automotive Technology 29(1) (2013), 1114-1122.

[10] Masjuki H., Abdulmuin M.Z., Sii H.S., Investigation on preheated palm oil methyl esters in the diesel engine, Proceeding Institute of Mechanical Engineering 21 (1996), 131-138.

[11] Onukwuli D.O., Optimization of Biodiesel Production from Refined Cotton Seed oil and its Characterization, Egypt. J. Petrol, (2016).

[12] Zheng M., Reader T., Hawley J., Diesel Engine Exhaust Gas Recirculation a Review on Advanced and Novel Concepts, Energy Conservation and Management 45 (2004), 883-900.

[13] Wagner L.E., Clark S.J., Schrock M.D, Effect of Soybean Oil Esters on the Performance-Lubrication Oil and Water of Diesel Engines, Society of Automotive Engineers, (1984).

[14] Prem Anand B., Saravanan C.G., Ananda Srinivasan C, Performance and Exhaust Emission of Turpentine Oil Powered Direct Injection Diesel Engine, Renew Energy 35 (2010) 1179–1184.

[15] Raheman H., Ghadge S.V, Performance of Diesel Engine with Biodiesel at varying Compression Ratio and Ignition Timing, Fuel 87 (2008) 2659–2666.

[16] Srinivasa Rao P., Gopalakrishnan K.V., Vegeable Oils and Methyl Esters as Fuels for Diesel Engines, Indian Journal of Science and Technology 29 (1991), 292-7.


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