PERFORMANCE ANALYSIS OF 4 STROKE CI ENGINE USING RENEWABLE FUEL NEEM OIL BLEND WITH DIESEL

On the bases of the experimental study performed on a four-cylinder, four-stroke, direct-injection diesel engine fueled with Neem biodiesel–diesel blends, both in the presence and absence of fuel additives, several important conclusions were obtained. The engine's performance and exhaust emission characteristics were systematically analyzed and compared against those recorded for standard diesel fuel under similar operating conditions. v  Neem biodiesel exhibits properties Neem biodiesel exhibits fuel properties that are generally ssimilar to those of conventional diesel fuel, although its heating value is approximately 10.17% lower. Due to this lower energy content, the peak power produced by pure Neem biodiesel is marginally less than that achieved with mineral diesel. In addition, the kinematic viscosity of Neem biodiesel is nearly 180% greater than that of diesel, resulting in the generation of larger fuel droplets during the injection process. Consequently, an increased fuel injection pressure is required to improve atomization and ensure efficient combustion within the engine cylinder is required to achieve finer atomization and improved combustion. v  The brake thermal efficiency (BTE) recorded for B20 and B40 blends is 49.34% and 43.98%, respectively, which is higher than the 39.78% observed for diesel. In contrast, the maximum BTE for B60 is 38.63%, slightly below that of diesel. The comparatively high viscosity of B60 results in larger droplet size and inferior atomization, thereby reducing combustion efficiency. The highest BTE achieved during the tests was 42.36% at a brake power of 20.34 kW, representing an improvement of 6.45% over diesel. v  The minimum brake specific energy consumption (BSEC) values for diesel, B20, and B40 were 9.04811 MJ/kWh, 8.35475 MJ/kWh, and 8.499496 MJ/kWh, respectively. Among these, B20 demonstrated the lowest BSEC, followed by B40 and diesel. Increased viscosity of higher blends, without modifying injection pressure, causes larger droplet formation and altered spray characteristics compared to diesel. v  The reduced BSEC observed for B20 and B40 can be attributed to their inherent oxygen content, higher cetane number, moderate viscosity, and shorter combustion duration relative to diesel. The lowest BSEC for B60 was 9.31528 MJ/kWh, which is about 3% higher than the minimum value obtained with diesel. v  The high exhaust gas temperature (EGT) recorded was 364°C for B60 at a brake power of 25.42 kW, while the minimum EGT of 238°C was observed for B20 at 5.08 kW. Compared to B60, B20 showed nearly a 34% reduction in EGT. At 25.42 kW, diesel and B40 produced maximum EGT values of 350°C and 342°C, respectively. Except for B20, all other blends exhibited higher EGT than diesel. Elevated EGT generally indicates increased heat carried away by exhaust gases and may correspond to reduced thermal efficiency. A compact combustion chamber design may also limit heat transfer to cylinder walls, contributing to higher exhaust temperatures. v  Carbon monoxide (CO) emissions at 25.42 kW were 0.0212% (Vol.) for diesel, 0.02098% for B20, 0.02066% for B40, and 0.02024% for B60. Diesel produced the highest CO emissions at this load. As the proportion of Neem biodiesel increased in the blend, CO emissions decreased, primarily Thanks to the oxygen content of biodiesel, which promotes more complete combustion, lower CO emissions are achieved for diesel, B20, B40, and B60 were 0.01696%, 0.0159%, 0.01643%, and 0.01402% (Vol.), respectively, at 15.25 kW. v  Hydrocarbon (HC) emissions were highest at idle and decreased continuously as braking performance improved for all fuels. Blending neem biodiesel with diesel reduced HC emissions across the entire load range, and a higher biodiesel content further lowered HC levels. Among all fuels, B60 exhibited the lowest HC emissions. The maximum HC emissions at no load were 11 ppm for diesel, 10 ppm for B20, 9 ppm for B40, and 8 ppm for B60. Using B60 reduced HC emissions to nearly half of those observed with diesel, mainly due to the oxygen content in Neem biodiesel, which enhances oxidation of unburned hydrocarbons.

1)               Vara Prasad Anumukonda, Prof. Navdeep Sharma Dugala (2023) “Preparation of biodiesel and experimental investigation of biodiesel blends on diesel engine at varying speed”. ICASF-2022 IOP Conf. Series: Earth and Environmental Science 1110 (2023) 012007 IOP Publishing doi:10.1088/1755-1315/1110/1/012007 2)               Duraisamy Sakthivadivel,Poongavanam GaneshKumar,Rajendran Prabakaran, V.S Vigneswaran, Kamaraj Nithyanandhan, Sung Chul Kim (2022) “A neem oil-based biodiesel with DEE enriched ethanol and Al2O3 nano additive: An experimental investigation on the diesel engine performance” Volume 34, June 2022, 102021,  https://doi.org/10.1016/j.csite.2022.102021 3)               M. Mathiyazhagan, K. Meenakshi Sundaram, G. Bupesh (2022) “Production and emission evaluation of neem biodiesel blends in a single cylinder diesel engine”,  Volume 62, Part 4, 2022, Pages 2124-2132 https://doi.org/10.1016/j.matpr.2022.03.047. 4)               Md Modassir Khan, Arun Kumar Kadian, Rabindra Prasad Sharma, S M Mozammil Hasnain, Ahmed Mohamed, Adham E. Ragab, Ali Zare (2023) “Emission Reduction and Performance Enhancement of CI Engine Propelled by Neem Biodiesel-Neem Oil-Decanol-Diesel Blends at High Injection Pressure” Sustainability 2023, 15(11), 9084; https://doi.org/10.3390/su15119084 Original submission received: 6 April 2023 / Revised: 19 May 2023 / Accepted: 26 May 2023 / Published: 5 June 2023. 5)               B. Prbakaran *, Dinoop Viswanathan (2016) “Effect of Blending Various Biodiesels with Diesel on Performance and Emissions of Diesel Engine: A Review”. 6)               S V Channapattanaa*,Kantharaj Cb,(2015) “Emissions and performance evaluation of di ci - vcr engine fuelled with honne oil methyl ester /diesel blends”. 7)               Al_Dawodya*, S.K. Bhattib (2014) “Experimental and Computational Investigations for Combustion, Performance and Emission Parameters of a Diesel Engine Fueled with Soybean Biodiesel-Diesel Blends”. 8)               S. M. Ameer Uddina*, A. K. Azadb,(2015) “Performance of a Diesel Engine run with Mustard-Kerosene blends”. 9)               T. Pushparaja*, S. Ramabalanb,(2013) “Green fuel design for diesel engine, combustion, performance and emission analysis”. 10)            Gaurav Dwivedi *, Mahendra Pal Sharma (2015) “Experimental Investigation of metals and Antioxidants on Oxidation Stability and Cold flow properties of Pongamia Biodiesel and its blends”.