Faculty Publications
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Item Performance Emission and Combustion Characteristics of CRDI Engine Operating on Jatropha Curcas Blend with EGR(Elsevier Ltd, 2018) Bedar, P.; Kumar, G.N.The present experimental study uses dual cylinder common rail direct injection (CRDI) engine fuelled by Jatropha curcas biodiesel blends produced through Transesterification process along with application of water cooled exhaust gas recirculation (EGR) rates. Performance, emissions and combustion properties of an engine at constant speed were measured and analysed. The improvement in brake thermal efficiency (BTE) along with reduction in carbon monoxide (CO), unburned hydrocarbons (UBHC) and smoke opacity were observed for the B20 biodiesel blend with a marginal increase in oxides of nitrogen (NOx). EGR application has reduced the NOx emissions and peak pressure inside the combustion chamber due to lower flame temperature. Combining B20 blend ratio with 15% EGR rate has the potential to achieve ultra-low NOx without affecting other type of diesel engine exhaust emissions by maintaining same efficiency level. © 2018 Elsevier Ltd.Item Performance and emission analysis of a single cylinder CI engine using Simarouba glauca biodiesel(Springer Heidelberg, 2017) Bedar, P.; Chitragar, P.R.; Shivaprasad, K.V.; Kumar, G.N.It is well known fact that diesel engines are commonly used for transportation and power generation due to their high efficiency, low fuel consumption and durability. On contrary these engines churn out harmful and hazardous emissions like particulate matter (PM) and nitrogen oxides (NOx). Recently Bio-origin renewable fuels have taken center stage of discussion because of their ability to replace depleting fossil fuels and capacity to reduce hazardous engine exhausts emissions when used in diesel engines. In the present experimental study Simarouba glauca biodiesel is used in a naturally aspirated four stroke single cylinder air cooled direct injection kirloskar DA10 engine. The main objective is to investigate the effect of biodiesel and exhaust gas recirculation (EGR) on the performance and emission characteristics of a CI engine at 180 bar fuel injection pressure (FIP) with standard injection timing. B20, B40 biodiesel blends with 10, 15 and 20% EGR ratios were used for the study to investigate brake thermal efficiency (BTE), carbon monoxide (CO), unburned hydrocarbons (UBHC), NOx, and smoke opacity. Reduction in CO, HC and smoke opacity is noticed with simarouba biodiesel fuel while increasing NOx compared to diesel. Application of EGR along with biodiesel resulted in simultaneous reduction of nitrogen oxides and smoke without affecting engine performance. It was found from experiment that B20 blend at 15% EGR shown superior performance characteristics compared to other conditions. © Springer India 2017.Item Computational analysis of unsteady flow in turbine part of turbocharger(Springer Heidelberg, 2017) Rao, H.K.S.; Raviteja, S.; Kumar, G.N.Turbocharging technique is widely employed in internal combustion engines to improve the performance and to reduce the exhaust emissions. Flow analysis through the turbocharger has been a guiding method to optimize the turbocharger design. Usually, the turbocharger turbine is analyzed at steady states. But in practical scenario the turbine operates with unsteady flow due to the reciprocating motion of exhaust port and creates unsteady environment in the turbine. In order to increase turbine efficiencies and effective engine turbocharger matching, proper understanding of unsteady flow physics within the turbine is essential. Currently the turbine and compressors maps are obtained by using 1D code which includes extrapolation techniques. These methods neglect heat transfer and windage effects, hence resulting in lower aerodynamic efficiencies. Three dimensional analysis could lead to a better estimation of the flow field, helping the designer to build a high efficiency turbocharger. The present article concentrates on investigating unsteady flow field in the turbine part of a turbocharger. The necessary unsteady conditions at turbine inlet were obtained using commercially available one dimensional engine simulation software AVL Boost. A turbocharged twin cylinder CRDI diesel engine test rig was modelled within the workspace. The exhaust mass flow rate, pressure and temperature were recorded as a function of crank angle. These results were used as the boundary condition for the 3D analysis of the turbine. ANSYS CFX tools were used to solve the unsteady case. The turbine geometry was generated using ANSYS bladegen. The model selected for analysis is k-? turbulence Model. The pulsating performance, effect of secondary flows and entropy generation are discussed in the paper. © Springer India 2017.Item Effect of exhaust gas recirculation on a CRDI engine fueled with waste plastic oil blend(Elsevier Ltd, 2018) Ayodhya, A.S.; Lamani, V.T.; Bedar, P.; Kumar, G.N.The inevitable rise in the usage of plastic poses a serious threat to the environment owing to their non-biodegradable nature. The lack of proper infrastructure for treating and recycling plastic wastes give rise to the disposal problem. However, the oil synthesized from these waste plastics can be used as an alternative fuel for C.I engines which not only helps to tackle the disposal problem but also aids in recovering precious energy from these wastes. This experimental investigation aims to study the effects of plastic-diesel blend(P30) fuel on the performance, emission and combustion characteristics of a twin cylinder CRDI engine operating at different EGR rates (0%, 10% and 20%). The experimental results showed a slight drop in the engine performance while operating with plastic blend, mainly overall due to its higher viscosity and lower heating value. The vast upsurge of NOX emissions with plastic blend was mitigated by the aid of EGR methodology. Marginal increase in the discharge of regulated emissions like HC, CO and soot were noticed for both plastic blend as well as EGR operations. The experiments were carried out for five different loading conditions varying from 0% to 80% in steps of 20% each and found out that waste plastic-diesel blend can be successfully used as an alternative fuel in diesel vehicles without any prior modifications in the engine. © 2018 Elsevier LtdItem Effect of hydrogen enrichment on performance, combustion, and emission of a methanol fueled SI engine(Elsevier Ltd, 2021) Nuthan Prasad, B.S.; Pandey, J.K.; Kumar, G.N.The study of potentially high rated alternative fuel (Methanol) for the IC engines is an exciting topic in the recent research advancement. However, the study of combination of methanol and hydrogen is considered to address both economic and environmental needs. Hydrogen with best combustion characteristics will compensate for the drawbacks of methanol as a fuel. In the present investigation hydrogen enrichment to methanol has shown a significant enhancement in performance and combustion; the overall emission has reduced substantially. The experiments for a different set of trials, including hydrogen enrichment ranging between 5% and 20% with 2.5% increment, the engine is operated with wide-open throttle (WOT) condition for different speeds. The increase in enrichment of hydrogen has shown a rise in BTE, BP, and a reduced BSEC value. The percentage increase in BTE is between 20 and 30%, and an increase in hydrogen beyond 12.5% would affect the volumetric efficiency, and thus performance declines after that. The exhaust emissions have a huge impact on hydrogen enrichment; CO, HC, and CO2 emission are reduced by 30–40%; however, an increase in cylinder temperature due to rapid combustion slightly increases the NOx emission. Thus hydrogen enriched methanol operating at higher compression ratio can improve the overall engine characteristics significantly. © 2021 Hydrogen Energy Publications LLCItem Effect of variable compression ratio and equivalence ratio on performance, combustion and emission of hydrogen port injection SI engine(Elsevier Ltd, 2022) Pandey, J.K.; Kumar, G.N.The present study includes an experimental investigation of the performance, combustion, and emission parameters of a hydrogen port fueled SI engine under wide-open throttle. The compression ratio (CR) is varied from 10 to 15, equivalence ratio (φ) from 0.4 to 1.0, and speed from 1400RPM to 1800RPM. The ignition timing is maintained at 20° before the top dead center. The brake thermal efficiency increases by nearly 10% from CR10 to CR15, and it also increased by 13.7% by changing φ from 0.4 to 0.9. Similarly, BP increases in the same fashion. The combustion enhances with an increase in peak pressure by increasing CR from 10 to 15 and φ from 0.4 to 0.9; however, φ 1.0 exhibits a negative trend. However, the NOX emission increases continuously with CR and φ, and so as the exhaust gas temperature. The carbon-based emissions are negligible, and volumetric efficiency decreases with φ and increases with CR. © 2021 Elsevier LtdItem Effect of parallel LPG fuelling in a methanol fuelled SI engine under variable compression ratio(Elsevier Ltd, 2022) Dinesh, M.H.; Pandey, J.K.; Kumar, G.N.In the present experimental study, five LPG fractions from 25% to 45% based on total energy are tested in a methanol fuelled SI engine at compression ratios (CR) varying from 12 to 15. Results are affirmative towards methanol/LPG dual fuel. The brake power, brake thermal efficiency, and volumetric efficiency are found to increase by 51%, 21.2%, and 13% respectively by changing from 25% LPG fraction at CR12 to 45% LPG fraction at CR15. The flame development period is found to decrease with CR and LPG, while the flame propagation period and total combustion duration are found to decrease with CR but increase with LPG. The maximum cylinder pressure and net heat release rate are found to increase by 101% and 27.8% respectively and advanced. CO emissions are found to decrease with CR while increase with LPG fraction. HC is found to decrease with LPG as well as CR. CO2 emissions are found to increase continuously with increasing LPG fractions and CR. The NOx emissions are also found to increase explicitly with LPG and CR, a net 209% increase in it is found 25% LPG at CR 12–45% LPG at CR15. © 2021 Elsevier LtdItem Study of performance, combustion, and NOx emission behavior of an SI engine fuelled with ammonia/hydrogen blends at various compression ratio(Elsevier Ltd, 2022) Dinesh, M.H.; Pandey, J.K.; Kumar, G.N.In the present paper, an experimental investigation has been performed under variable CR and 1400&1800RPM speed at a fixed spark timing of 24ºCA BTDC under wide-open throttle conditions. The hydrogen blending is performed based on energy fractions from 5% to 21% of the total fuel energy. With increasing compression ratio (CR), the flame development gets faster, and the flame propagation speed improves, leading to a short combustion period. Similarly, increasing hydrogen fraction improves combustion, resulting in a rapid rise in pressure and temperature. Despite a 13.64% decrease in volumetric efficiency from 5% to 21% hydrogen fraction at 1400 and 1800 RPM, BP and BTE increased by 16.89% and 33%, respectively. The slow-burning properties of NH3 extend the combustion period, resulting in a long-delayed burning period. As a result, the temperature of the low-hydrogen fraction of the exhaust gas is higher. As the hydrogen fraction and CR increase, this effect decreases, resulting in lower EGT. The hydrogen addition increases the peak temperature; therefore, NOx increases continuously with increasing hydrogen despite reducing ammonia. Ammonia is a key element used to reduce NOx from vehicles. A practical solution for controlling the NOx due to the ammonia/hydrogen blend is selective catalytic reduction (SCR). © 2022 Hydrogen Energy Publications LLCItem Experimental investigation of variable compression ratio and ignition timing effects on performance, combustion, and Nox emission of an ammonia/hydrogen-fuelled Si engine(Elsevier Ltd, 2023) Dinesh, M.H.; Kumar, G.N.In the present experimental study hydrogen-assisted ammonia combustion strategy is used in a SI engine with variable ignition timings (18ºCA bTDC to 32ºCA bTDC) and wide-open throttle conditions, CR changes (14–16) at 1400RPM and 1800RPM. This article aims to optimize ignition timing to boost efficiency and power without knocking. It has been established that ammonia/hydrogen fuels are a clean energy source capable of reducing pollution caused by undesirable emissions. The results revealed that increasing the CR from 14 to 16 increased brake power, brake thermal efficiency, NOX, cylinder pressure, and net heat release rate by 36.82%, 25.11%, 30.21%, 10.35%, and 9.53%, respectively. CA10-90 and EGT, on the other hand, are reduced. Increased speed reduces volumetric efficiency by 9.5% at 1800 RPM. In each CR, 28ºCA bTDC ignition timing and 21% hydrogen energy fraction performed well, which can be observed. Hence, the experiment results indicate hydrogen can be used as a combustion promoter, establishing a new standard for developing ammonia-fuelled engines. © 2023 Hydrogen Energy Publications LLCItem Experimental investigation and optimization of performance, emission, and vibro-acoustic parameters of SI engine fueled with n-propanol and gasoline blends using ANN-GA coupled with NSGA3-modified TOPSIS hybrid approach(Elsevier Ltd, 2024) Kirankumar, K.R.; Kumar, G.N.; Kamath, N.; Gangadharan, K.V.In the present study, performance, emission, and vibro-acoustic studies were conducted on a spark ignition (SI) engine fueled with gasoline and an n-propanol blend at variable compression ratio (CR), speed, and propanol blend fraction (PBF). Experimental data were used to model an artificial neural network (ANN) trained with a genetic algorithm (GA). ANN predictive responses were employed to establish regression relationships between brake power (BP), brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), oxides of nitrogen (NOx), carbon monoxide (CO), hydrocarbon (HC), resultant vibration acceleration (RVA), and sound pressure level (SPL) with operating parameters using response surface methodology (RSM). These models served as objective functions in the non-dominated sorting genetic algorithm-3 (NSGA3), a multi-objective optimization (MOO) technique, to optimize responses and obtain non-dominated solutions. These solutions were filtered using a modified technique for order preference by similarity to the ideal solution (TOPSIS) to obtain a compromised optimal solution. ANN-GA model outcomes showed high accuracy, with coefficient of determination (R2) and root mean square error (RMSE) values ranging from 0.979 to 0.993 and 0.0381 to 0.0643, respectively. NSGA3 coupled with modified TOPSIS identified optimal operating conditions at 1271.77 RPM, a CR of 11.96, and a PBF of 33.26 %. © 2024 Elsevier Ltd