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 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 Experimental studies on the influence of axial and radial fields of sintered neo-delta magnets in reforming the energy utilization combustion and emission properties of a hydrocarbon fuel(Taylor and Francis Ltd., 2024) Oommen, L.P.; Kumar, G.N.Permanent magnets based on rare earth components have been increasingly finding their applications in modern technologies. Although the magnetic properties tend to deteriorate rapidly at temperatures in excess of 150ºC, sintered NdFeB magnets can be employed in reforming the physical and combustion properties of hydrocarbon fuels. In the present investigation, two different magnetization patterns of high-grade NdFeB magnets are applied in varying intensities on a multicylinder MPFI engine fueled by gasoline and the alteration in combustion and emission properties of the fuel are studied. The magnetic field restructures the hydrocarbon molecules and causes the pseudo clusters to break away thus reducing the inherent viscosity and enhancing the association of hydrocarbon molecules with the oxidizer. The effectiveness of two different magnetization patterns of sintered NdFeB magnetic material in reforming the combustion characteristics is studied and compared. The study shows a maximum increase of 9.2% in power output and 7.74% in thermal efficiency of the test engine along with a significant reduction in the generation of toxic emissions that are the byproducts of combustion. The study also concludes that radial magnetic fields are more effective in conditioning the fuel and reducing the emission of CO, HC, and NOx by 8.57%, 5.52%, and 1.25% compared to the same intensity fields under axial magnetization. The combustion behavior of gasoline is studied under both field patterns. The statistical analysis of mean effective pressures through radar plots is conclusive of the reduction in cycle by cycle variations under magnetic field-assisted combustion. Abbreviations: NdFeB:Neodymium Iron Boron permanent magnet; SmCo:Samarium Cobalt permanent magnet; MPFI:Multipoint Port Fuel injection; BP:Brake Power; BTE:Brake Thermal Efficiency; BSFC:Brake Specific Fuel Consumption; NHRR:Net Heat Release Rate; IMEP:Indicated Mean Effective Pressure; COV:Coefficient of Variation; CO:Carbon Monoxide; CO2:Carbon dioxide; HC: hydrocarbon; NOxOxides of Nitrogen. © 2020 Taylor & Francis Group, LLC.