Tailored Ir–In/CeO₂ nanocatalyst for diesel emissions: A multiscale study from synthesis to engine deployment

The present study intends to explore the effect of the addition of fuel additives with camphor oil (CMO) on the characteristics of a twin-cylinder compression ignition (CI) engine. The lower viscosity and boiling point of CMO when compared to diesel could improve the fuel atomization, evaporation, and air/fuel mixing process. However, thelower cetane index of CMO limits its use as a drop in fuel for diesel in CI engine. In general, NOX emission increases for less viscous and low cetane (LVLC) fuels due to pronounced premixed combustion phase. To improve the ignition characteristics and decrease NOX emissions, fuel additives such as diglyme (DGE)-a cetane enhancer, cumene (CU)-an antioxidant, and eugenol (EU) and acetone (A)-bio-additives, are added 10% by volume with CMO. The engine used for the experimentation is a twin-cylinder tractor engine that runs at a constant speed of 1500rpm. The engine was operated with diesel initially to attain warm-up condition, which facilitates the operation of neat CMO. At full load condition, brake thermal efficiency (BTE) for CMO is higher (29.6%) than that of diesel (28.1%), while NOX emission is increased by 9.4%. With DGE10 (10% DGE + 90% CMO), the ignition characteristics of CMO are improved and BTE is increased to 31.7% at full load condition. With EU10 (10% EU + 90% CMO) and A10 (10% A + 90% CMO), NOX emission is decreased by 24.6 and 17.8% when compared to diesel, while BTE is comparable to diesel. While HC and CO emission decreased for DGE10 and CU10, they increased for EU10 and A10 when compared to baseline diesel and CMO.

Addition of two kerosene-based fuels to diesel–biodiesel fuel: Effect on combustion, performance and emissions characteristics of CI engine

The demands on future energy conversion technologies are becoming increasingly stringent. Biofuels, which are considered to have a critical role in meeting growing energy needs, must find increasing avenues for compliance. Accordingly, ternary fuel blends have received significant attention because their physiochemical properties can be very similar to diesel, while overcoming some challenges associated with traditional biofuel use. Consequently, this work assesses the use of alcohol-biodiesel-vegetable oil blends in Compression Ignition (CI) engines. Three ethanol-biodiesel- vegetable oil blends were developed using 10%, 20% and 30% alcohol and their performances were compared to diesel and neat coconut oil. These blends were tested in a single cylinder diesel engine and their performances assessed using energy, emissions and exergy analyses. The results indicated that the blends had better brake thermal efficiency (BTE) values than diesel at high to medium loads, with the E30 blend having the highest BTE value of 31% at full load conditions as compared to 28.9% for diesel. The blends were also found to be comparable to diesel based on a First Law energy analysis. Additionally, it was found that the blends had better nitric oxides (NO) emission levels than diesel; at full load conditions, the E30 blend had the lowest value of 281 ppm as compared to diesel having a value of 299 ppm. However, they were found to have comparable levels for the other emissions characteristics that were examined. Further, the Second Law analyses indicated that the blends made better use of their fuel energy potential and thus, can be considered as a more suitable fuel for CI engine combustion. Collectively, the results suggest that the ternary blends are a viable candidate for future energy conversion via CI engines

ABSTRACTAchieving the new emission norms is a difficult task to today’s compression ignition (CI) engine without any exhaust gas after-treatment technologies. It is necessary to find the practical method which reduces the unsafe emission, with minor modifications of the CI engine. Dual fuel homogeneous charge compression ignition (HCCI) engine has been recognised as one of the solutions to minimise the emissions and achieve higher performance. In the present study the dual fuel HCCI engine mode of operation carried out by supply of ethanol fuel-air mixture to the engine cylinder through the carburetor and diesel fuel is directly injected at the end of compression for the initiation of ignition. Dual fuel HCCI engine is one of the most promising engines suitable for alternative fuels and lower NOX emissions. An experimental investigation is carried out on dual fuel HCCI engine. Fuel consumption and exhaust emissions such as NOX, CO2, CO, HC are measured and compared with conventional CI engine. The results show that NOX emission tends to decrease at low and moderate loads of the engine, but at full load condition it is slightly higher. Further, thermal efficiency is calculated and compared in CI engine; it is observed that there is a slight improvement in thermal efficiency at high load operation. In the dual fuel HCCI engine mode, there is a provision to use of ethanol or any other alternate fuel for better energy efficiencies and low NOX emission.

This paper describes the conceptual design and aerothermal approach of the ABB ALSTOM POWER UK Limited (ABB ALSTOM POWER) dry low emission (DLE) combustion system directed towards all current and future power ranges. A set of parameters was employed as a common criterion to design the company's combustion system across the product range. The parameters made it possible to scale the combustion system to operate at any required firing temperature without the penalty of achieving the low emission targets. The logic and sensible air mass mapping and testing management based on a basic knowledge of the aerothermodynamics of the combustion system and its integral parts produced reliable operation and engine results. The combustion system aerothermodynamic design considers the constraints of maintaining combustor specifications while introducing a reliable ultra-low NO x concept with minimal structural change to engine design. Furthermore, the ignition loop, piloting and stability margins were issues continuously assessed through a defined application programme to examine their impact on engine operability at various load conditions. A main radial swirler injector is utilized for both gas and liquid to produce a fuel lean mixture for combustion at full-load operating conditions, while a pilot fuel injector guarantees a local fuel-rich zone to sustain stability at low power conditions. The carefully planned switch-over between the pilot and main swirler provides smooth operation and low emission across the load range conditions. The company combustion system relies upon the principle of aerodynamic variable mixing with a single vortex generator burner. The partial premixing process takes place at the radial inflow swirler slots before the fuel—air mixture is introduced into a prechamber and thereafter into the combustion chamber. For vane passage injection the liquid liquid fuel atomization should be at an optimum and the vane passage and prechamber length set to provide the vaporization period. The impingement cooling scheme aided by a thin layer of thermal barrier coating (TBC) achieved an excellent combustor wall temperature at all operating conditions and across the DLE engines product range. The scheme made it possible to direct a large amount of air towards the swirler to achieve the lean premix combustion. Substantial CO emission reduction at part load was achieved by variable guide vanes (VGV) modulation for the single-shaft engines. This action inhibits NO formation without slowing the CO oxidation process to a frozen condition. The variable mixing regime approach and accurate air management has demonstrated an ultra-low NO x emission of 12–15 and 32–35 ppmv (corrected to 15% O2) at the full-load condition while operating on gas and distillate-2 fuel respectively. Moreover, the system exhibited low CO and dynamics oscillation capability for both gas and liquid fuel operation. At the present time, the one-dimensional analysis has been proved to be a reliable tool for combustion system designers to produce a preliminary design configuration. The particular choice for a commercial computational fluid dynamics (CFD) code to satisfy various criteria of the swirling combusting flow is proving to be difficult due to constraints regarding slover and/or methods limitation. The results obtained from the high-pressure air facilities, engine beds and field trials represent a true technological achievement through collective engineering design efforts towards emission and pollution control for small- and medium-range gas turbine engines.

Energy scarcity and pollution problems have prompted researchers to search for renewable and clean energy sources for compression ignition (CI) engines. Two C8 biofuels, i.e., n-octanol and di-n-butylether (DnBE), are both promising to be the diesel fuel candidates because of their good ignition ability. However, their physical and chemical properties are different from each other. Thus, the combustion process of a CI engine could be optimized by manipulating the blending ratio of n-octanol and DnBE. In this work, to investigate the effects of n-octanol and DnBE blends on the combustion characteristics and emissions formation in a CI engine, the numerical investigation was carried out by the coupled KIVA4-CHEMKIN code. A multi-component reaction mechanism was implemented in the code to mimic the combustion of the fuels. Different DnBE/n-octanol blends were designed by varying the DnBE from 10% to 90% with an interval of 10% on an energy basis. Then the CI engine fueled with pure n-octanol, pure DnBE, and their blends was simulated at the engine speeds of 1500 rpm and 2280 rpm, respectively. Results suggest that blending more DnBE in octanol can shorten the ignition delay, increase peak pressure, mitigate pressure rise rate, and prolong the combustion duration. The emitted CO of the n-octanol fueled CI engine is high at both speeds. Blending DnBE in n-octanol can reduce CO emissions but inevitably leads to a rise in NO. More importantly, soot-free combustion can be achieved by fueling either n-octanol or DnBE. Finally, the optimal DnBE blending ratio is selected at 50%, of which IMEP can be improved by 6.12% and 6.9%, and CO can be reduced by 69.91% and 65.98% with acceptable increases in NO at 1500 and 2280 rpm, respectively. This implies that the optimization of CI engines can be achieved by adjusting the blending ratio of n-octanol and DnBE.

Performance and emission of a diesel engine using different water/waste fish oil (WFO) biodiesel/diesel emulsion fuels: Optimization of fuel formulation via response surface methodology (RSM)

This article aims to study the impact of camphor oil premixing with intake air on compression ignition (CI) engine characteristics powered with jatropha oil and cottonseed oil. The experiment is conducted on the direct injection compression engine attached to the premixing setup. The investigation reveals that premixing of camphor oil with cottonseed oil and jatropha oil escalates the thermal brake efficiency to 35.02% and 33.62% and brings down the brake‐specific energy consumption to 10.27 and 10.70 kJ kWh−1. At all loading conditions, the premixing of camphor oil and the rise of camphor oil in premixing proportions increase the volumetric efficiency and cut the exhaust gas temperature. 20% premixing of camphor oil with cottonseed oil and jatropha oil drops the smoke opacity emissions by 22.23% and 11.86% and NO emission by 23.27% and 14.59%, respectively, at full load conditions. Further, it shows a 27.60% and 21.14% hike in CO emissions and a 31.34% and 31.87% hike in HC emissions at full load conditions. The in‐cylinder pressure, heat release rate, and mean gas temperature increase with increasing the energy share of camphor oil in premixing. Overall, the premixing of camphor oil shows better CI engine attributes except HC and CO emissions.

The present investigation is to study the effect of Nano-fuel additives [Magnalium (Al-Mg) and cobalt oxide (Co <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> )] on the performance and emission characteristics of Jatropha biodiesel (B100) in a single cylinder, air cooled, direct injection diesel engine. Ball mill (Magnalium) and Sol-Gel (Cobalt oxide) processes were adopted for Nano-particle preparation. The obtained particle size range is from 38-70 nm. The particle size is characterised using scanning electron microscope (SEM). The Nano particles (100 mg/l) were dispersed in the fuel by an ultrasonicator with the assistance of optimised surfactant concentration. It was noticed that the addition of Nano cobalt oxide additive reduced specific energy consumption at part load and full load conditions. Cobalt oxide acts as an oxygen buffer which improves the combustion and reduces the emissions. The introduction of Nano-fuel additive resulted in maximum reduction of about 60% in unburnt hydrocarbon (UBHC) and 50% reduction in carbon monoxide at full load and 75% load respectively for neat biodiesel operation. It was observed that NO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> emission were higher at neat biodiesel operation compared with neat diesel operation and it was countered by introduction of Nano-fuel additive which resulted in 45% reduction in NO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> emission at the same biodiesel operation. Magnalium particles are highly energetic materials and it reduces the energy consumption and improves the thermal efficiency, the reason is that, the additive releases energy during combustion, in addition to the liquid fuel. Magnalium improves the atomisation by means of micro explosion phenomena and hence it reduces the pollution formation. Due to micro explosion, the air/fuel mixing will be proper and hence it results in 70% reduction in HC emission and 41% reduction in CO emission for B100 with additive at part load and full load conditions respectively. It was also noticed that, additive act as a heat sink and reduces the in-cylinder temperature which results in 30% reduction in NO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> emission at 75% load for B100 with additive.

Catalytic performance of NO oxidation over LaMeO3 (Me = Mn, Fe, Co) perovskite prepared by the sol–gel method

China originally planned to use fuel ethanol gasoline nationwide in 2020, and taking corn as an important raw material of ethanol gasoline, this paper analyzed the life cycle cost model of corn fuel ethanol gasoline and traditional gasoline from production to consumption, including internal and external cost calculations. The internal cost is the actual cost of the industry chain, while the external cost is converted into the cost value by examining the environmental impact of pollutant emission levels in each stage of the life cycle of ethanol gasoline production. Based on this model, by selecting the project data of specific regions and manufacturers in China, it can be calculated as follows: The main links affecting the internal cost of ethanol gasoline production are crude oil procurement cost, refinery and ethanol plant construction cost; The main influencing link of external cost is the emission of ethanol gasoline combustion, including the fuel, power and other energy consumption factors in the production of ethanol and gasoline; The cost can be optimized from the perspective of production technology, technological process, energy material consumption and various labor costs. Assuming E10 is used in the whole Chinese market, the empirical results are as follows: among the pollutants produced by the use of ethanol-added gasoline in the whole region, CO2 emission reduction is the largest, exceeding 53 million tons, followed by CO and wastewater emission reduction of 1.78 million tons and 1.58 million tons respectively. In terms of the conventional gasoline, the CO emission reduction of about 20% is the largest, followed by about 17% reduction of HC, about 15% reduction of SO2 and about 9% reduction of CO2 respectively. These results show that the promotion of ethanol gasoline (E10) usage in China has a considerable reduction effect of emission if the availability of raw materials are sufficient. The life cycle external cost of ethanol gasoline is 11.45%, lower than that of conventional gasoline. In 2019, China’s fuel ethanol production capacity was 4.15 million tons, and the actual production was about 3 million tons. Assuming that all of it were used to produce E10 ethanol gasoline, compared with traditional gasoline consumption, the emission reduction benefit of E10 gasoline would be nearly $84.7 million.

The two main issues at present are environmental pollution and the depletion of fossil fuels. To solve these issues, researchers have experimented with several biofuels for compression ignition (CI) engines. Waste cooking oil (WCO) was discovered to be an excellent alternative fuel for CI engines due to its widespread availability, biofuel, cost-effectiveness and renewable nature. Unfortunately, WCO's low fuel qualities caused CI engines' performance was low and exhaust emissions were high as a result of poor combustion. A single cylinder, four stroke, direct injection, water cooled CI engine was used for this study. In the first phase of work, experiments were conducted using diesel and one-time used waste cooking oil (OTWCO) as fuels. Then in the second phase, OTWCO was converted into one time used waste cooking oil biodiesel (OTWCOB) through transesterification process and experiments were repeated. In the third phase of work, titanium dioxide Nano-fluids were prepared by solgel method, and blended with OTWCOB and experiments were conducted. Finally, all the experimental outputs from various techniques were compared and analysed. It was observed that OTWCO produced lower brake thermal efficiency (BTE) with higher exhaust emissions than diesel. BTE was improved while using OTWCOB as compared to OTWCO. HC, CO emissions and smoke opacity were reduced. But Nitric Oxide (NOx) emission was increased as compared to diesel. Further, it was found that BTE was improved while using titanium dioxide Nano fluids blended with OTWCOB. Exhaust emissions and smoke were drastically reduced while using OT-WCOB-N.

Dimethyl ether fuel injection system development for a compression ignition engine for increasing the thermal efficiency and reducing emissions

Fuel composition impact on heavy duty diesel engine combustion & emissions

Transport facility is the key parameter for development of any country. Worldwide countries are facing the green house effect and environmental pollution problem. The limited and quickly depleting fossils fuel resources have promoted research for second generation fuels for their use in Compression Ignition (CI) engines. Biodiesel [Jatropha Methyl Ester] is the second generation fuel which can be used as an alternative fuel in CI engine. Jatropha Methyl Ester extracted from Jatropha Curcas which can be grown on degraded and forest land with small irrigating maintenance. In this work, the experiments are conducted on CI engine for various operating parameters viz, Compression Ratio, Fuel Injection Pressure, Fuel Fraction, and Injection Timing with four levels each under full load condition. This study aims to find the optimum level of operating parameters as well as develop regression model of the output variables viz, vibration (RMS value of acceleration) of engine head in linear and lateral directions under full load condition as a function of operating parameters. Taguchi’s L 16 orthogonal array is applied for reducing the number of runs and time for experiment. Vibration characteristics in linear direction and lateral direction are measured under different levels of operating parameters with full load condition. It was found that the acceleration in linear direction is more as compared to acceleration in lateral direction for each experimental run. Compression Ratio and Fuel Fraction are the significant parameters for corresponding linear and lateral vibration. For linear vibration, optimum levels of operating parameters are; 16.5 Compression Ratio, Pure diesel, 250 bar Injection Pressure and 23 0 bTDC Injection Timing are found. Similarly, 17.5 Compression Ratio, 30% Fuel Fraction, 270bar Injection Pressure and 25 0 bTDC Injection Timing are found for lateral vibration.