Faculty Publications
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Item An Experimental Study on Combustion and Emission Analysis of Four Cylinder 4-Stroke Gasoline Engine Using Pure Hydrogen and LPG at Idle Condition(Elsevier Ltd, 2016) Chitragar, P.R.; Shivaprasad, K.V.; Nayak, V.; Bedar, P.; Kumar, G.N.Fluctuation in oil prices and stricter exhaust emission norms were the main reasons wakening every researcher to search for suitable and feasible alternative fuels for automotive use. Among the available option gaseous fuels find their best position because of their compatible physical-chemical properties and ecofriendly nature than present fossil fuels. Hydrogen's combustion properties like high energy content, high heating value, wide range of flammability and low ignition energy with almost least toxic emissions are favorable to use in an IC engine as an alternative fuel. Liquid petroleum gas (LPG) has lower carbon content, higher calorific value, octane number and flame propagation speed will improve the emission results compared to gasoline fuel. This paper describes an experimental results carried out to evaluate the combustion and emission performance of a Maruti Suzuki make, spark ignited four cylinders, four stroke engines at idle condition by using pure hydrogen, LPG and gasoline. The engine was adjoined with Electronic Control Unit (ECU) assisting hydrogen and LPG injector system keeping gasoline line unchanged. Tests were carried out by using compressed hydrogen gas regulated by two stage pressure reduction from cylinder to atmospheric value and by using vaporizer pressure for LPG. For comparison engine was run first by gasoline and then by pure hydrogen and LPG. Study revealed that there was increment of 13% cylinder pressure for pure hydrogen and decrement of 4.5% cylinder pressure for LPG when compared to gasoline. The burn duration for pure hydrogen, LPG and gasoline were found to be increasing respectively which infers that hydrogen has very short combustion duration and gasoline higher. It was observed that toxic emissions like Carbon monoxide (CO), Hydrocarbons (HC) and Oxides of Nitrogen (NOx) were improved for pure hydrogen than LPG and gasoline. © 2016 The Authors.Item Effect of hydrogen addition on the performance and emission parameters of an SI engine fueled with butanol blends at stoichiometric conditions(Elsevier Ltd, 2015) Raviteja, S.; Kumar, G.N.Hydrogen is considered as the best fuel due to its excellent combustion properties. But its use as a fuel is confined by its low energy density. In the present investigation an attempt has been made to utilize some of the benefits of hydrogen by using it as an additive in a butanol fueled engine. The experimental study has been carried out on a 4 stroke, single cylinder, manifold electronic fuel injected (EFI) engine mapped to run at stoichiometric conditions. Butanol blends were chosen as the base fuel due to their higher energy density compared to ethanol. A small fraction of hydrogen was injected into the air stream. The engine was run at 3000 RPM at full load condition. The performance, emission and combustion parameters are compared for four concentrations of butanol (10%, 20%, 30%, and 100% by volume of fuel) and two concentrations of hydrogen (5%, and 10% by volume of air) with gasoline. The results indicated that the efficiency of the engine improved upon hydrogen enrichment. An average of 60% reduction was observed in HC and CO emissions with 10% enrichment of hydrogen, whereas the NO emissions almost doubled itself. The combustion analysis showed reduced delay periods, shorter combustion durations, higher cylinder pressures, higher temperatures and improved combustion. © 2015 Hydrogen Energy Publications, LLC.Item Experimental Investigation of Variations in Spark Timing using a Spark-Ignition Engine with Hydrogen-Blended Gasoline(Wiley-VCH Verlag info@wiley-vch.de, 2015) Shivaprasad, K.V.; Chitragar, P.R.; Kumar, G.N.This study describes an experiment conducted using an electronically controllable single-cylinder high-speed gasoline engine to analyze the performance and emissions characteristics of various hydrogen-gasoline blends. The experiments have been conducted for various engine speeds and spark timings at the wide open throttle position. The experimental results revealed that the engine brake thermal efficiency and brake mean effective pressure first increase and then decrease with the increase engine speed at all spark timings. The minimum amount of brake specific energy consumption was observed for 20% hydrogen addition in the total fuel blend at 3000rpm engine speed and 14°crank angle (CA) before top dead center (BTDC) spark timing. Hydrocarbon and carbon monoxide emissions were reduced with the retardation of spark timings. Nitrogen oxide emissions were continuously increased with the addition of hydrogen in the fuel blend as well as spark timing advance. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Item Influence of spark timing on the performance and emission characteristics of gasoline–hydrogen-blended high-speed spark-ignition engine(Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2017) Shivaprasad, K.V.; Chitragar, P.R.; Nayak, V.; Kumar, G.N.This article experimentally investigates the effect of spark timing on performance and emission characteristics of high-speed spark-ignition (SI) engine operated with different hydrogen–gasoline fuel blends. For this purpose, the conventional carbureted SI engine is modified into an electronically controllable engine, wherein an electronically controllable unit was used to control the ignition timings and injection duration of gasoline. The tests were conducted with different spark timings at the wide open throttle position and 3000 rpm engine speed. The experimental results demonstrated that brake mean effective pressure and engine brake thermal efficiency increased first and then decreased with the increase in spark advance. Peak cylinder pressure, temperature and heat release rate were increased until 20% hydrogen addition and with increased spark timings. NOx emissions were continuously increased with the increment in both spark timings and hydrogen addition, whereas hydrocarbon emissions were increased with spark timings but decreased with hydrogen addition. CO emissions were reduced with the increase in spark timing and hydrogen addition. © 2016 Informa UK Limited, trading as Taylor & Francis Group.Item 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 Effects of hydrogen assisted combustion of EBNOL IN SI engines under variable compression ratio and ignition timing(Elsevier Ltd, 2022) Pandey, J.K.; Kumar, G.N.Alcohols are oxygenated fuels, holding a good reputation among alternatives, but single alcohol does not possess all qualities. Besides, the high latent heat and low vapor pressure limit their uses in SI engines. Hence, an energy enhancing and combustion promoting fuel helps overcome the drawbacks, among all available hydrogen fits the race most. Hence, hydrogen-assisted combustion of equivolume blend of ethanol/butanol (ENBOL) is experimentally tested under various compression ratios (CR) (11–15), ignition timing (16°CA-24°CA BTDC) for three hydrogen fractions (5%–15%) at three speeds (1400RPM-1800RPM). The experimental outcome notices an increase in brake power (BP), brake thermal efficiency (BTE), peak pressure (Pmax), heat release rate (HRRmax), and NOx emissions with increasing CR and Hydrogen addition. The combustion duration, CO, and UBHC emissions reduce while CO2 emissions reduce with hydrogen; increasing CR notices a drop in CO2 at a much advanced or much-delayed ignition. Hydrogen improves combustion but reduces volumetric efficiency; increasing CR improves it, and hydrogen effect reduces with increasing CR. BP, BTE, and CA10-90 improve with retarding ignition from 24°CA, while CA10, Pmax, and HRRmax reduce continuously. UBHC and CO emissions increase while NOx reduces with retarding ignition. The ignition timing of 20°CA at CR15 and 15% hydrogen performed better than gasoline. © 2022 Elsevier LtdItem A comparative study of NOx mitigating techniques EGR and spark delay on combustion and NOx emission of ammonia/hydrogen and hydrogen fuelled SI engine(Elsevier Ltd, 2023) Pandey, J.K.; Dinesh, M.H.; Kumar, G.N.IC engines, the backbone of the transportation sector is facing energy insecurity and stringent environmental norms motivating researchers to look for alternate ways of revival. In pursuit hydrogen and its careers are seen as promising option. Aiming the same comparative-study is performed on NH3/H2 (7:3) and hydrogen under varying ignition (from −24°CA to −12°CA) and EGR rates (till 25%). Results indicate improved combustion for NH3/H2 for a small range of ignition than hydrogen, ∂P/∂θ and ∂Q/∂θ is improved before TDC and deteriorates after it. Cycle-by-cycle variations increase for a longer ignition range for NH3/H2, but NOx drops more rapidly. At −24°CA, NH3/H2 has observed a minimal gap in peak pressure, CoV and performance from hydrogen. Though a small EGR helps reduce NOx, cycle-by-cycle variations and CA90 reduce due to improved combustion for NH3/H2. ∂P/∂θ and ∂Q/∂θ improve for the same range too. However, hydrogen suffers adverse effects due to EGR that intensify with increasing EGR-rate. At higher EGR, unstable combustion and heterogeneity prevail, resulting in increased cycle-by-cycle variations and a rapid drop in peak pressure. The prolonged combustion witnesses a massive decline in NOx for both fuels; however, the gap between NH3/H2 and hydrogen entities reduces. NH3/H2 shows better efficiency than hydrogen for an efficient NOx control. However, higher fuel NOx maintains a significant difference for NH3/H2 than hydrogen. The study limits quantitative analysis of it and also NH3 emissions, which is another primary concern. © 2023 Elsevier LtdItem Study of combustion and emission of a SI engine at various CR fuelled with different ratios of biobutanol/hydrogen fuel(Elsevier Ltd, 2023) Pandey, J.K.; Kumar, G.N.The global requirement is shifting to territorial independence of energy sources, and the introduction of alcohols and biofuels are the primary sectors. Recently agriculture products-based ethanol has replaced a larger portion of gasoline. Butanol is another impressive fuel in the same chain, much better than ethanol in many parameters. Butanol has certain limitations, too, such as higher latent heat and low heating value. Therefore, biobutanol/hydrogen is tested experimentally at various compression ratios (CR) in the present study. Brake thermal efficiency was not significantly changed by CR at 90% butanol, while CR is more impressive with increasing hydrogen. The flame development period was reduced by 34%, while the flame propagation phase was reduced by 29% by increasing CR to 15 and hydrogen to 25%. Peak pressure and heat release rate surged by 12.89% and 12.32% and advanced by 6°CA. The coefficient of variations is also reduced by 21% by increasing CR to 15 and hydrogen to 30%. Higher hydrogen faced combustion difficulties due to increasing stratification and heterogeneity during combustion. Unlikely to trend, Tmax (peak cylinder temperature) and NOx were continuously increased with CR and hydrogen due to increased fuel quantity and larger mass burning before TDC. However, CO and HC emissions were reduced by CR due to increased BTE (brake thermal efficiency) and reduced by hydrogen due to less HC supply. A slight increase in HC and CO was noticed for higher hydrogen due to local heterogeneity and disassociation at high temperatures. © 2023 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 LLC