Faculty Publications
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Item Investigation of preheated Dhupa seed oil biodiesel as an alternative fuel on the performance, emission and combustion in a CI engine(Elsevier Ltd, 2021) Kodate, S.V.; Satyanarayana Raju, P.; Yadav, A.K.; Kumar, G.N.The present study investigates the suitability of preheated Vateria indica methyl ester (VIME) as an alternative fuel for a diesel engine. VIME is a renewable, non-toxic and sustainable alternative biodiesel obtained from Dhupa fat by transesterification. This study aims to evaluate the combustion, performance, and emission characteristics of four different blends such as B0 (0% VIME and 100% mineral diesel), B30, B50 and B100 at elevated fuel inlet temperatures ranging from 35 °C to 95 °C. The tests are carried out in a single cylinder diesel engine at optimum loading condition and fixed speed. Results are obtained in terms of brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), in-cylinder pressure, heat release rate and exhaust emissions (CO, HC, NOX, CO2 and soot). It is observed that the preheating of blends decreases the viscosity which enhances fuel spray characteristics, leading to higher engine performance, lower CO and HC emissions with a slight increase in NOX and CO2 emissions. BTE and peak in-cylinder pressure for B100 at 95 °C and 75% load are increased by 7.44%, 2.97% respectively compared to unheated B100 biodiesel. BSFC, CO, HC emissions at 75% load for B100 at 95 °C are reduced by 26.73%, 28.08%, 42.7% respectively compared to unheated B100. © 2021 Elsevier LtdItem Extraction and characterization of coffee husk biodiesel and investigation of its effect on performance, combustion, and emission characteristics in a diesel engine(Elsevier Ltd, 2022) Emma, A.F.; Sathyabhama, A.; Yadav, A.K.Biodiesel and its blends with diesel are used in engines to overcome the problems of environmental pollution and fast depletion of conventional fuels. The purpose of this research is to extract oil from coffee husk, convert it into coffee husk oil methyl ester (CHOME) by transesterification, and test the suitability of this biodiesel as an alternate, renewable, sustainable fuel for a diesel engine. The physicochemical characteristics of the developed biodiesel are studied and compared with regular diesel. The results showed that the fundamental properties of the produced fuel are comparable to that of diesel. The performance, combustion, and emission characteristics of a diesel engine fueled with CHOME biodiesel are investigated. The experiments are conducted in a single-cylinder direct injection diesel engine at a constant speed by varying the loads (0, 25, 50, 75, and 100%) for different biodiesel-diesel blends (B10, B20, B30, B40, B50, and B80), and the results are compared with the baseline diesel. The brake thermal efficiency (BTE) of the blends, B10, B20, B30, and B50 dropped by 0.6, 0.7, 1.29, and 3%, respectively compared with the neat diesel. Similarly the brake specific energy consumption (BSEC) is reduced by 0.1, 0.3, 0.44, and 0.77% for B10, B20, B30, and B50, respectively. Exhaust gas emissions are reduced for all biodiesel-diesel blends. Compared to regular diesel, at full load, CO, HC, and smoke opacity of B30 reduced by 13.2%, 4%, and 12%, respectively. CO2 of B30 at full load is increased by 8.63%. In general, it can be stated that CHOME biodiesel is a promising alternate biodiesel that can be used in an internal combustion engine without major modifications. © 2022 The AuthorsItem Effect of DEE added Karanja biodiesel fuel on the performance, combustion and emission characteristics of CI engine under variable injection timing and engine load(Taylor and Francis Ltd., 2023) Wogasso Wodajo, A.; Yadav, A.K.; Gottekere Narayanappa, K.The higher density and viscosity of biodiesel reduce the engine's performance due to poor atomisation. The present study aims to investigate the effect of DEE and injection time on engine characteristics fueled with KME-diesel blends. For this purpose, single cylinder CI engine is used. The injection timing is advanced and retarded by 2° from the base injection timing (27° bTDC), and the load is varied from 0% to 100%. The addition of DEE to the blends results in a reduction of density and viscosity. At 29° bTDC, the brake thermal efficiency for 5% DEE is increased by 3.1% compared to a blend without DEE at full load. For 5% DEE, compared to 27° bTDC, 29° bTDC reduces the HC and CO emission by 4.5% and 42.8%, respectively at full load. It is concluded that the 5% DEE operating at 29° bTDC improves the engine's performance with a small rise in NOX emission. Highlights: DEE added biodiesel blend has lower viscosity and density than biodiesel. 5% DEE addition in biodiesel blend at advanced injection timing improves BTE and reduces emission. Lower in-cylinder temperature is achieved due to higher latent heat of evaporation. The CO and HC emissions for B25DE5 at 29° bTDC are reduced by 4.5% and 42.8% than 27° bTDC at full load. At advanced injection timing NOX emission for 5% DEE addition increased by 2.7% than 27° bTDC. © 2022 Informa UK Limited, trading as Taylor & Francis Group.Item EXTRACTION AND CHARACTERIZATION OF BIODIESEL DERIVED FROM THE COFFEE HUSK AND ITS EFFECT ON DIESEL ENGINE PERFORMANCE AND EMISSION CHARACTERISTICS(Begell House Inc., 2023) Emma, A.F.; Sathyabhama, A.; Yadav, A.K.This study investigates the suitability of coffee husk (CH) and spent coffee ground (SCG) as the biomass energy source to produce biodiesel. The chemical composition was determined using the field emission gun scanning electron microscope (FEG-SEM). The carbon and oxygen concentration in CH was 49.84% and 48.06%, respectively, by weight. The SCG had 67.72% of carbon and 26.18% of oxygen by weight. The oil extracted from CH was converted into biodiesel using the transesterification process. The properties of the biodiesel, such as flashpoint, fire point, viscosity, calorific value, and density, were measured. The engine's performance and emission characteristics were investigated by blending the produced biodiesel with regular diesel. It was found that by using CHOME biodiesel-diesel blends, exhaust gas emissions such as HC, CO, and smoke opacity were considerably reduced, while CO2 and NOx emissions increased. The brake thermal efficiency (BTE) of the engine was slightly reduced, and brake specific energy consumption (BSFC ) was increased. © 2023 by Begell House, Inc.Item Computational fluid dynamic analysis of the effect of inlet valve closing timing on common rail diesel engines fueled with butanol–diesel blends(Frontiers Media SA, 2024) Lamani, V.T.; Shivaprasad, K.V.; Roy, D.; Yadav, A.K.; Kumar, G.N.The inlet valve closing (IVC) timing plays a crucial role in engine combustion, which impacts engine performance and emissions. This study attempts to measure the potential to use n-butanol (Bu) and its blends with the neat diesel in a common rail direct injection (CRDI) engine. The computational fluid dynamics (CFD) simulation is carried out to estimate the performance, combustion, and exhaust emission characteristics of n-butanol–diesel blends (0%–30% by volume) for variable valve timings. An experimental study is carried out using standard valve timing and blends to validate the CFD model (ESE AVL FIRE). After validation, the CFD model is employed to study the effect of variable valve timings for different n-butanol–diesel blends. Extended coherent flame model-3 zone (ECFM-3Z) is implemented to conduct combustion analysis, and the kappa–zeta–f (k–ζ–f) model is employed for turbulence modeling. The inlet valve closing (IVC) time is varied (advanced and retarded) from standard conditions, and optimized valve timing is obtained. Advancing IVC time leads to lower cylinder pressure during compression due to reduced trapped air mass. The brake thermal efficiency (BTE) is increased by 4.5%, 6%, and 8% for Bu10, Bu20, and Bu30, respectively, compared to Bu0. Based on BTE, optimum injection timings are obtained at 12° before the top dead center (BTDC) for Bu0 and 15° BTDC for Bu10, Bu20, and Bu30. Nitrogen oxide (NOx) emissions increase due to complete combustion. Due to IVC timing, further carbon monoxide and soot formation decreased with blends and had an insignificant effect. © © 2024 Lamani, Shivaprasad, Roy, Yadav and Kumar.