An experimental study on performance emissions and combustion characteristics of a CI engine running

Abstract

Keywords: Citrullus Colocynthis; Combustion; Diesel Engine; Emission; Performance

Introduction

A pivotal role in transportation is played by internal combustion engines. Finding alternative fuels is essential because combustion emissions worsen air pollution and accelerate global warming [1]. The dependence on fossil fuels may be reduced by obtaining energy from renewable sources such as biomass, wind, and solar energy. Since it is renewable and environmentally beneficial, biodiesel made from vegetable oils and animal fats is a viable diesel

alternative [2]. Experiments employing pure and modified vegetable oils in both edible and non-edible forms demonstrated that they can entirely or substantially replace diesel [3]. Despite the potential of edible oils to replace diesel fuel in a variety of ways, diversifying feedstocks for biodiesel production should be a strategic objective for governments [4]. All studies revealed that adding different amounts of palmarosa oil to diesel may significantly lower the emissions of unburned HC, CO, NOx, and exhaust smoke.

*Corresponding author. *E-mail address: balumitauto@gmail.com This paper was recommended for publication in revised form by Editor-in-Chief Ahmet Selim Dalkılıç Published by Yıldız Technical University Press, İstanbul, Turkey Copyright 2021, Yıldız Technical University. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

By marginally increasing the amount of fuel used for the brakes, castor oil biodiesel lowered HC and CO emissions by 10%. Citrullus Colocynthis seed oil typically contains between 16 and 52 percent of the total oil source and over 84 percent of unsaturated fats. This results in biodiesel and melon as a common name. Although this species is widely distributed in places like India, the Middle East, and the Mediterranean area, it is less common in Africa and is most common in Iran, tropical Asia, and Algeria. In a single-cylinder, stationary, four-stroke diesel engine [5] investigated the performance and emissions of several fuels derived from linseed, mahua, and rice bran. With LOME mixes, they have not encountered similar problems. They concluded that the 20% LOME mix increased the engine›s thermal efficiency while reducing smoke density and BSFC. Pongamia pinnata oil and its derivatives have been investigated for its potential and benefits as a diesel engine fuel by Milano et al. [6], we have looked into and compared the fuel qualities of pogamia pinnata oil to those of diesel. It has been discussed how to develop peak pressure using biodiesel, how to study heat release rates, and how to analyze engine vibrations when using the fuel. Biodiesel reduces particulate matter, carbon monoxide, and unburned hydrocarbon emissions from diesel engines, they claim. Calophyllum inophyllum oil was transformed into a hydrocarbon fuel using fly ash catalyst, according to Saravanan et al. [7]. They showed that the B25-powered engine behaved more like a diesel engine and that greater mixtures resulted in worse brake thermal efficiency. As a result, the B25›s smoke, hydrocarbon, and carbon monoxide emissions were comparable to those of diesel, while its nitrogen oxide emissions were less than those of diesel. Jatropha biodiesel affects the torque and

thermal efficiency of a conventional diesel engine, according to study by Vijay Kumar et al. [8], with the decline becoming more obvious as the biodiesel concentration of the mixture increases. By blending biodiesel into blended fuels, BSFC is impacted. Mixed fuels containing a higher percentage of biodiesel have higher cylinder peak pressures and shorter ignition delay times. When compared to using pure diesel, using jatropha biodiesel produces more NOx emissions. The amount of jatropha biodiesel in the blends increases, which lowers the emissions of PM and smoke. Jatropha biodiesel increases the quantity of carbon dioxide released at the exhaust of diesel engines [9]. There has been a comprehensive and in-depth analysis of the literature. It illustrates that a standard DI diesel engine can run on both clean and mixed vegetable oil. Only lesser mixtures are advised over the long run. Fuel must undergo transesterification in order to be utilised in higher mixes, however this modification has no effect on engine efficiency or emissions [10]. However, research on biodiesel engine modifications is scarce in the literature. Citrullus Colocynthis oil biodiesel is investigated in this study in a single-cylinder 4 stroke DI engine.

Materials And Methods

Preparation of Citrullus Lanatus The blooming plant Citrullus Lanatus, which resembles a vine, is native to southern Africa. It is a vital part of the Cucurbitaceae family from an economic perspective. Throughout Egypt, the Middle East, and Africa, it has been grown for a very long time. The fleshy interior of the water

Table 1. Compared to diesel, the characteristics of biodiesel mixes Properties

melon fruit (the mesocarp and endocarp) contains crimson pulp and watery juice, as well as a thick, smooth rind (the exocarp). 60% of the watermelon fruit is flesh, and 90% of it is liquid with 7–10% w/v sugars (Table 1). As a result, the fruit of the watermelon is quickly fermentable to a liquid in excess of 50% [11]. It has been proven that lycopene, a beneficial antioxidant found in Citrullus Lanatus, lowers the risk of heart attacks and cancer cells. (Figure 1).

Experimental Setup

In the experimental study, a single-cylinder, direct-injection, four-stroke, water-cooled, compression-ignition (CI) engine was used. Table 2 contains the engine›s technical specifications. The time it took to consume a known amount of gasoline (10cc) from a burette was recorded in order to calculate the fuel flow rate. A red wood viscometer was used to measure the viscosity of raw and esterified oil, a hydrometer to assess density, a bomb calorimeter to measure calorific value, and an open cup to measure flash and fire point (Table 3). HC, CO, and NOx emissions from the exhaust tailpipe were recorded using an AVL-444 DI Gas Analyzer. The engine was first made to run in perfect conditions as a warm-up phase before the experimental testing began, and then the experiments were carried out. After starting, the engine was given around 10 minutes to warm up. Five distinct part load scenarios, namely 20%, 40%, 60%, 80%, and 100%, were used to test the engine (Figure 2).

Results And Discussion

Brake Thermal Efficiency Figure 3 depicts the fluctuation of brake thermal efficiency with brake power for various biodiesel mixes. At all power outputs, it was discovered that biodiesel blends had worse brake thermal efficiency than diesel. The calorific value of the fuel determines how much energy is used and how much braking power is applied to the diesel engine. Based on research findings, it was determined that biodiesel will have higher BTE rates than mineral diesel due to its higher oxygen content and better fuel-rich combustion. Due to larger fuel droplet size, a greater fuel density, a

Hydrocarbon (HC) Emissions Figure 5 depicts the change of hydrocarbon emissions with brake power for various biodiesel mixes. Increases in load have been found to have a linear relationship with increases in unburned hydrocarbon emissions. This is because there is proportionately less oxygen available for the reaction when more petrol is put into the engine cylinder while the engine is operating at a high load. Due to the greater density and viscosity of Citrullus Colocynthis plain oil, mixture formation is weak and certain hydrocarbons are only partially burnt during combustion. Carbon Monoxide (CO) Emissions Figure 6 illustrates how carbon monoxide emissions change as a function of brake power for various biodiesel Figure 3. Illustrate the deviation of BTE and brake power. higher fuel presence in the combustion chamber, deprived atomization, and less volatile fuel, the test fuel blends diesel (29.4%), B20 (28.6%), and B75 (26.9%) had a minimum rate of BTE at higher load compared to mineral diesel [12]. Brake Specific Fuel Consumption Figure 4 depicts the fluctuation of brake specific fuel consumption with brake power for various biodiesel mixes. Brake specific fuel consumption falls with increasing load. When compared to diesel, it has been found that biodiesel blends have greater brake specific fuel consumption. A higher calorific value of a fuel will result in a higher rate of evaporation, thereby improving combustion. Because biodiesel blends are less calorific than diesel, they evaporate more slowly. Slower evaporation rates increase the amount of fuel required for the brakes [13].

Figure 4. Variation of brake specific fuel consumption with brake Power.

blends. Citrullus Colocynthis oil had a greater concentration of CO emissions than regular diesel fuel under all loading conditions. This was brought on by the Citrullus Colocynthis oil’s poor atomization and poor combustion properties. When compared to Citrullus Colocynthis (B75) oil, the carbon monoxide emissions from the blends are significantly lower. With the B10 blend, the combustion rate has improved, resulting in better fuel and spray distribution inside the combustion chamber and a decrease in CO emissions. Mohammed et al. [12] found similar carbon monoxide emission outputs. Nitrogen Oxide (NOx) Emissions Figure 7 depicts how Nitrogen Oxide emissions change as a function of brake power for various biodiesel mixes. Only a some of the factors that influence NOx formation include premixed combustion, in-cylinder pressure, in-cylinder temperature, oxygen concentration, and residence time. Oxides of nitrogen are created when an airborne nitrogen molecule combines with an oxygen molecule at a higher temperature. As load increases, NOx emissions rise as a result of the elevated temperature inside the combustion chamber. Based on a certain NOx value, the B75 and its combinations produce more pollutants than diesel. This demonstrates that B20 has fewer NOx emissions when compared to diesel. Due to the decreased premixed burning rate after the delay interval, the NOx emissions have decreased. There was a slight rise in NOx levels as a result of the increased mix of diesel and Citrullus Colocynthis oil [8]. Smoke Figure 8 depicts the fluctuation of smoke opacity with brake power for several biodiesel mixes. The results showed that the amount of smoke rises as engine output power increases. The main cause of the rise in smoke emissions

Figure 8. Smoke vs brake power. is the greater fuel consumption necessary to deliver a constant-speed engine with the same amount of power as diesel fuel. The high viscosity and low volatility of the Citrullus Colocynthis oil, however, resulted in subpar atomization and slow burning. For diesel, the equivalent smoke emissions for B20, B25, B50, and B75 mixtures at full load are 64HSU, 66HSU, 68HSU, 70HSU, and 76HSU. More Citrullus Colocynthis oil in the mixes improves the fuel’s ability to burn as the amount of oxygen in the fuel increases [14]. In-Cylinder Pressure In-cylinder pressure refers to the pressure created at the engine’s cylinder during the power stroke, which produces the output work from the thermal energy of the fuel burning rate that was evaluated. The incorrect atomization of the fuel mixes, low calorific value, increased fuel density and cetane number, short ignition delay time, and low rate of fuel burning in the combustion chamber would all contribute to this. However, compared to mineral diesel, the B20 had a faster rate of in-cylinder pressure rise than the B75 due to the fuel blend’s lower cetane number, better combustion, and longer ignition delay (Figure 9) [14]. Heat Release Rate Figure 10 shows the various HRR curves for diesel engines and their crank angles for all fuel mixes. The figure gave the impression that diesel fuel had a greater peak HRR range than the other fuel blends because diesel had a higher crank angle than B50, B75, and B20 (108.5 kJ/deg), 89.54 kJ/deg, and 60.27 kJ/deg, respectively. A greater rate of cetane number, less ignition delay, and calorific value with a lower rate of oxygen delivery might cause this [15].

best performance with the fewest emissions out of all the evaluated biodiesel blends. 3. The inflation, ignition delay, and combustion duration would be longer as compared to biodiesel blends (10.5%). In future studies will be required to examine the effects of different compression ratios and to discriminate between the combustion analysis of diesel and biodiesel blends with different EGR rates. However, in terms of economy and emissions, the B10 blend performs more similarly to diesel fuel.

Authorship Contributions

Authors equally contributed to this work. Figure 9. Exhibit the varied range of in-cylinder pressure curve and brake power.

Data Availability Statement

The authors confirm that the data that supports the findings of this study are available within the article. Raw data that support the finding of this study are available from the corresponding author, upon reasonable request.

Conflict Of Interest

The author declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Ethics

There are no ethical issues with the publication of this manuscript.

Conclusion

The following conclusions were reached based on the experimental results: 1. At all power levels, diesel was shown to be more effective at braking than biodiesel blends. Biodiesel blends (14.6%) have a higher brake-specific fuel consumption than diesel fuel.

2. When compared to diesel fuel and biodiesel blends, B20

emits fewer hydrocarbon emissions. In comparison to diesel, B20 produces less carbon monoxide emissions. Regular diesel produces more nitrogen oxide emissions than biodiesel blends do. Plain diesel has less opacity in the smoke than biodiesel blends. B20 demonstrated the

Menon K, Sood N, Rao NK. Study of morpho-agronomic diversity and oil content in desert gourd (Citrullus Colocynthis (L.) Schrad.). Aust J Crop Sci 2016;10:1000−1006. [CrossRef] Venkatesan B, Seeniappan K, Shanmugam E, Subramanian S, Veerasundaram J. Characterization and effect of the use of safflower methyl ester and diesel blends in the compression ignition engine. Oil Gas Sci Technol Rev IFP Energies Nouv 2021;76:29. [CrossRef]

Sudeshkumar MP, Xavier JF, Balu P, Veerasundaram J, Sudhakar K. Waste plastic oil to fuel: An experimental study in thermal barrier coated CI engine with exhaust gas recirculation. Environ Qual Manage 2022:1−7. [CrossRef] Balu P, Vasantkumar P, Govindan P, Sathish T. An experimental investigation on ceramic coating with retarded injection timing on diesel engine using Karanja oil methyl ester. Int J Ambient Energy 2022;44:1031−1035. [CrossRef]

Vignesh P, Pradeep Kumar AR, Shankar Ganesh N, Veerasundaram J, Sudhakar K. Biodiesel and green diesel generation: An overview. Oil Gas Sci Technol Rev IFP Energies Nouv 2021;76:6. [CrossRef] Milano J, Ong HC, Masjuki HH, Silitonga AS, Chen W, Kusumo F, et al. Optimization of biodiesel production by microwave irradiation-assisted transesterification for waste cooking oil-Calophyllum inophyllum oil via response surface methodology. Energy Conver Manage 2018;158:400−415. [CrossRef] Saravanan P, Mala D, Jayaseelan V, Kumar NM. Experimental performance investigation of Partially Stabilized Zirconia coated low heat rejection diesel engine with waste plastic oil as a fuel. Energy Sources Part A Recovery Util Environ Eff 2019;45:11046−11059. [CrossRef] Vijay Kumar A, Veeresh Babu P, Ravi Kumar. Experimental investigation on the effects of diesel and mahua biodiesel blended fuel in direct injection diesel engine modified by nozzle orifice diameters. Renew Energy 2018;119:388−399. [CrossRef] Kivevele TT, Kristóf L, Bereczky Á, Mbarawa MM. Engine performance, exhaust emissions and combustion characteristics of a CI engine fuelled with croton megalocarpus methyl ester with antioxidant. Fuel 2018;90:2782−2789. [CrossRef] Stojanovic N, Belhocine A, Abdullah OI, Grujic I. The influence of the brake pad construction on noise

formation, people's health and reduction measures. Environ Sci Pollut Res Int 2023 ;30:15352−15363. [11]

Verma TN, Nashine P, Chaurasiya PK, Rajak U, Afzal A, Kumar S, et al. The effect of ethanol-methanol-diesel-microalgae blends on performance, combustion and emissions of a direct injection diesel engine. Sustain Energy Technol Assess 2020;42:100851. [CrossRef] Mohammed AA, Yaseen AA, Atiyah IK. Experimental study for the effect of damaged vegetable oil biofuels on diesel engine performance and exhaust emission. J Engineer Sci Technol 2021;16:1069−1080. Manigandan S, Gunasekar P, Devipriya J, Nithya S. Emission and injection characteristics of corn biodiesel blend in diesel engine. Fuel 2019;235:723−735.

Karthickeyan V. Effect of combustion chamber bowl geometry modification on engine performance, combustion and emission characteristics of biodiesel fuelled diesel engine with its energy and exergy analysis. Energy 2019;176:830−852. [CrossRef] Harigaran A, Balu P. An experimental study on the performance and emission characteristics of a single-cylinder diesel engine running on biodiesel made from palm oil and antioxidant additive. Int J Ambient Energy 2023;699:654−659.

Share and Cite