Prabhakar Sekar’s research while affiliated with Wollo University and other places

The world's biggest problems are global warming and fossil fuel depletion. Most fast‐developing countries are facing problems. Most engines that burn crude oil–based products discharge smoke, carbon monoxide, nitric oxide, unburnt hydrocarbon, and lower‐concentration particulate matter into the environment. In this study, good planning and emissions rules are reducing crude oil use. Juliflora oil biodiesel is derived from Juliflora seeds and tested in a single‐cylinder direct injection diesel engine. If you use biodiesel in your engine without changes, you may encounter gum formation in the cylinder, knocking, and carbon deposits. The blends approach is one of many techniques to change biodiesel's attributes, but our present intention is to employ it. B20 blend outperforms the other sample fuels and is closest to diesel. The produced aluminum oxide was tested for parameters using X‐ray diffractometer and scanning electron microscope. Aluminum oxide was blended with biodiesel using an ultrasonicated to mix 25, 50, and 75 parts per million (PPM) aluminum oxides, designated B20AO25 PPM, B20AO50 PPM, and B20AO75 PPM. For typical engine running and optimal engine operating parameters, biodiesel with aluminum oxide nanoadditives was investigated. Optimized characteristics are 80% diesel and 20% Juliflora seed oil with 75 PPM aluminum oxide nanoadditives (B20AO75 PPM) at 200 bar injection pressure and 21° before top dead center injection time.

Existing ecofriendly apprehensions about climate change have directed scientists to discover plant-based vegetable oils for use as fuels, such as straight vegetable oils and their biodiesels, because of their renewability, nontoxic nature, biodegradability, and environmental friendliness. This experimental study intended to reveal the tribological aspects of 90 °C preheated Jatropha curcas straight vegetable oil (PHSVO90) used in a 7.35 kW, 1000 rpm constant speed indirect injection (IDI) diesel engine and likened to conventional diesel operation by conducting an elongated term durability examination for 512 h as per IS:10000 standards. Tests were performed under encoded loading cycles in two segments: one with PHSVO90 and the second one with conventional diesel operation (CDO). Following the completion of these tests, all essential engine components were disassembled to assess physical deterioration and the accumulation of carbon deposits. Due to their different chemical compositions, PHSVO90 and diesel showed noticeable differences in their properties. PHSVO90 had a higher amount of carbon deposits, measuring 6.3 g. It also had a total acid number (TAN) of 9.11 mg KOH/g, a density of 986 kg/m³, and a viscosity of 381 cSt. In addition, an inductive plasma-based atomic emission spectroscope detected a greater amount of metal wear debris from spectrum metals with PHSVO90. The elements Fe, Cr, Al, Cu, Mg, and Pb exhibited concentrations 1.49×, 1.37×, 1.19×, 1.37×, 1.2×, and 1.18× higher, respectively, than those recorded during typical diesel operation. Wear of PHSVO90 fuel engine components like the cylinder head, cylinder bore/liner, piston, Gudgeon pin, small end bush of the connecting rod, big end bearing, crankshaft bearing, connecting rod bearing, and inlet and exhaust valves, along with guides, was detected to be marginally advanced compared to CDO. As per identified results, an appropriate maintenance protocol was developed for the PHSVO90 application. It is observed that, without any extensive modifications, PHSVO90 oil has proven to be a good substitute for IDI engines.

The study intends to calibrate the compression ignition (CI) engine split injection parameters as efficiently. The goal of the study is to find the best split injection parameters for a dual-fuel engine that runs on 40% ammonia and 60% biodiesel at 80% load and a constant speed of 1500 rpm with the CRDi system. To optimize and forecast split injection settings, the RSM and an ANN model are created. Based on the experimental findings, the RSM optimization research recommends a per-injection timing of 54 °CA bTDC, a main injection angle of 19 °CA bTDC, and a pilot mass of 42%. As a result, in comparison to the unoptimized map, the split injection optimized calibration map increases BTE by 12.33% and decreases BSEC by 6.60%, and the optimized map reduces HC, CO, smoke, and EGT emissions by 15.68%, 21.40%, 18.82, and 17.24%, while increasing NOx emissions by 15.62%. RSM optimization with the most desirable level was selected for map development, and three trials were carried out to predict the calibrated map using ANN. According to the findings, the ANN predicted all responses with R > 0.99, demonstrating the real-time reproducibility of engine variables in contrast to the RSM responses. The experimental validation of the predicted data has an error range of 1.03–2.86%, which is acceptable.

The ongoing depletion of the world's fossil fuel sources and environmental damage has compelled the quest for alternative energy. Excellent characteristics of biodiesel include its renewable nature, safety, absence of sulfur, environmental advantages, and biodegradability, which can eradicate the above problems. In this study, algal oil was characterized to obtain the fatty acid profile, and the free fatty acid value of algal oil suggested a two-step process of esterification and transesterification for efficient biodiesel production. The performance and emission results of biodiesel and its blends (B10, B20, and B30) were investigated in a constant speed, single-cylinder, 4-stroke, 3.5 kW compression ignition engine at different loads for arriving at an appropriate fuel blend ratio. The response surface methodology technique is used to predict the ideal composition of microalgae-diesel using the experimental data with due weightage for the optimization criterion. The predicted blend ratio of B25 was tested on the engine and authenticated. The findings recorded an improvement in brake thermal efficiency to 31.42% and reduction in brake specific energy consumption to 9.82 MJ/kW h, unburned hydrocarbon to 85 ppm, carbon monoxide to 0.164% v/v, carbon dioxide to 4.115% v/v, nitrogen oxides to 691 ppm, and smoke opacity to 16.93%.

Fossil fuel depletion and environmental pollution are paramount problems the world faces. Despite several measures, the transportation industry is still battling to manage these issues. A combined approach of fuel modification for low-temperature combustion with combustion enhancers could offer a breakthrough. Due to their properties and chemical structure, biodiesels have piqued the interest of scientists. Studies have asserted that microalgal biodiesel might be a viable alternative. Premixed charge compression ignition (PCCI) is an easily adoptable promising low-temperature combustion strategy in compression ignition engines. The objective of this study is to identify the optimal blend and catalyst measure for improved performance and reduced emissions. Microalgae biodiesel at various proportions (B10, B20, B30, and B40) was amalgamated with CuO nanocatalyst and tested to arrive at the right concoction of biodiesel with nanoparticles in a 5.2 kW CI engine for different load conditions. The PCCI function warrants that about 20% of the fuel supplied is vaporized for premixing. Finally, the interplay factors of the independent variables of the PCCI engine were then explored by response surface methodology (RSM) to determine the optimal level of desired dependent and independent variables. The RSM experiment findings suggest that the best biodiesel and nanoparticle concoctions at 20%, 40%, 60%, and 80% loads were B20CuO76, B20Cu60, B18CuO61, and B18CuO65, respectively. These findings were experimentally validated.

The present experiment deals with the study of the effect of addition of diethyl ether (DEE) on the performance and emission characteristics of a thermal-barrier-coated (TBC) engine run on papaw (Carica papaya) and eucalyptus oil blends. The fuels studied were test blends, CPME30Eu70 (papaw methyl ester 30% and eucalyptus oil 70%) and CPME30Eu70 + 10% DEE, and diesel. Optimum results were obtained for CPME30Eu70 with DEE in a TBC engine. The addition of DEE creates a lean mixture, and its low viscosity, high cetane number, and volatility improve the performance of biofuel-powered engines. The investigation shows that the addition of 10% DEE gives the best results in brake-specific energy consumption (BSEC), brake-specific fuel consumption (BSFC), and brake thermal efficiency (BTE). The BTE of the DEE-adapted CPME30Eu70 blend was 32.2%, whereas for diesel it was 31.8%, which was 1.2% higher than that of CPME30Eu70 at normal mode of operation. The addition of DEE to CPME30Eu70 reduced BSEC and BSFC by 8.9 and 7.2%, respectively, compared to a non-coated engine powered by CPME30Eu70. The combination of DEE and CPME30Eu70 nominally decreased nitrogen oxide emissions. The carbon monoxide and hydrocarbon emissions of CPME30Eu70 after DEE addition were 0.195% vol. and 38 ppm, respectively, which were 13.3 and 5.1% lower than those for CPME30Eu70 powered by a compression ignition engine. The experiment found that adding DEE to CPME30Eu70 could improve its atomization and spray characteristics. Moreover, the performance and emission characteristics of the CPME30Eu70-powered engine were enhanced.