Decrease In Hc Research Articles

Optimization for waste coconut and fish oil derived biodiesel with MgO nanoparticle blend: Grey relational analysis, grey wolf optimization, driving training based optimization and election based optimization algorithm

The present work aimed at the practical utility of waste hybrid (coconut + fish oil) oil-derived biodiesel with magnesium oxide (MgO) nanoparticles (NPs) fuelled to diesel engines. Central composite design (CCD) experimental matrices with different sets of variables (blend type: 10–40 % vol. of biodiesel; MgO NPs: 60–180 ppm; engine speed: 1000–2000 rpm; engine load: 40–100 %) were used to examine the engine performance (brake specific fuel consumption: BSFC; and brake thermal efficiency: BTE) and emission characteristics (carbon monoxide: CO; unburnt hydrocarbon: UHC; nitrous oxide: NOx). The MgO NPs are characterized by using an X-ray diffractometer: XRD, scanning electron microscope: SEM and transmission electron microscope: TEM and confirm the compositions and the crystallite particle size equal to 132 nm. The models developed for each output showed a better value of coefficient of determination (R2) equal to 0.9843 for BSFC, 0.9859 for BTE, 0.9772 for CO, 0.9777 for NOx, and 0.9368 for UHC. Grey relational analysis (GRA) with quality loss function (QLFs) and principal component analysis (PCA) were used to correlate the multiple responses and transform multiple objective functions to single objective function necessary for optimization. Three population-based search algorithms, such as driving training-based optimization (DTBO) and election-based optimization algorithm (EBOA) and grey wolf optimization (GWO), were applied and evaluated their optimization performances. EBOA, DTBO and GWO determined the same optimal conditions and converged to 1000 iterations with a computational time equal to 2, 5 and 30 s, respectively. The algorithms determined optimal conditions produced better experimental values than GRA-based QLF and PCA with 31.27 % decrease in BSFC, 24.27 % decrease in CO, 4.64 % decrease in HC, 19.82 % decrease in NOx emissions, and 9.82 % decrease in BTE, respectively. MgO NPs addition to biodiesel fuel resulted in better performance and emission characteristics than without MgO NPs.

Effect of using borax decahydrate as nanomaterials additive diesel fuel on diesel engine performance and emissions

Today, the increase in fuel consumption with the increasing number of vehicles has increased the efforts to make the engines more efficient. Diesel engines are subject to severe restrictions due to the emission problem. Although there is an emission problem, it is widely used especially in freight transportation. Many studies on diesel engines emission problems are made by academicians and manufacturers. In this sense, many studies have been carried out by adding nanomaterials to diesel fuel to reduce emissions in diesel engines. In this study, borax decahydrate as a fuel additive was studied in a diesel single-cylinder engine. Borax decahydrate was dissolved in 500 ml of methanol, 5 gr, 15 gr and 25 gr, and methanol was added to 10% diesel. To be 90% Diesel +10% Methanol (D90M10) 90% Diesel 10% Methanol + 1 gr Borax decahydrate (D90M10B1) 90% Diesel 10% Methanol + 3 gr Borax decahydrate (D90M10B2) 90% Diesel 10% Methanol + 5 gr Borax decahydrate (D90M10B3) four different fuel mixtures were tested. The experimental test measured in-cylinder pressure, heat release rate, fuel consumption, power, torque, exhaust gas temperature, smoke opacity, and exhaust emissions. Due to the rich oxygen content of borax decahydrate, it has been observed to reduce emissions, excluding NOx emissions. There was an increase in exhaust temperature, nitrogen oxides (NOx), and carbon dioxide (CO2) emissions and a serious decrease in HC, CO, brake-specific fuel consumption, and smoke opacity values. Studies should be expanded and enriched with different mixing ratios and usage patterns of boron-doped fuels in the future.

Combustion, Ecological, and Energetic Indicators for Mixtures of Hydrotreated Vegetable Oil (HVO) with Duck Fat Applied as Fuel in a Compression Ignition Engine

The aim of the present study was to investigate the effects of the application of hydrotreated vegetable oil (HVO) mixed with pure duck fat (F100) as fuel, replacing the conventional fossil diesel fuel (D100). The tests were performed using a four-stroke direct injection CI engine diesel engine. Six fuel samples were used: D100, HVO100, F100, as well as three HVO–fat mixtures F25, F50, and F75. To further study the main characteristics of fuel combustion, the AVL BOOST software (Burn program) was applied. The results of experimental studies showed that with the addition of pure fat to HVO, the ignition delay phase increased with an increase in the amount of heat released during the premix combustion phase and the pressure and temperature rise in the cylinder increased; however, the mentioned parameters were not higher as compared to diesel fuel. It was found that as the concentration of fat in the HVO–fat mixtures increases, the viscosity and density increases, while LHV was decreased, which thereby increases brake specific fuel consumption and slightly decreases brake thermal efficiency in comparison to diesel fuel. A decrease of CO2, HC, NOx emissions, and smoke was established for all HVO–fat mixtures as compared to diesel fuel at all loads; however; under low loads, CO emissions increased.

Pengaruh generator HHO dan etanol terhadap performa dan emisi gas buang mesin bensin

The large number of motorized vehicles in Indonesia cannot be separated from the rapid population growth. Fuel is one of the important components in vehicles, this is because the fuel produces heat energy to be converted into mechanical energy. So far, ordinary people only use fuel oil (BBM) based on the price per liter, assuming all fuel can be used in their vehicles. In fact, to get maximum performance and low exhaust emissions, it requires high octane fuel. The purpose of this study was to determine the effect of adding ethanol and HHO to fuel on engine performance and the resulting exhaust emissions. The test sample consisted of Pertamax fuel which was then mixed with 10% ethanol with the addition of HHO. Furthermore, the process of testing the performance of the vehicle's engine and the resulting exhaust emissions. The test results show that there is an increase in power and torque of 7.77 hp and 7.54 N.m, respectively, in the test of fuel mixing with the addition of HHO. Then the results of the exhaust gas test resulted in a decrease in CO and HC while the CO2 level increased by testing the mixing of fuel with ethanol accompanied by the addition of HHO. The average percentage scores for each test were 15.02%, 17.79%, and 16.72%.

Effect of Fe/Ni ratio on amorphization, crystallization kinetics, and magnetic properties of FeNiSiBCuNb alloys

In this work, the precipitation phase transformation, crystallization kinetics, and soft magnetic properties of (FexNi80-xSi9.5B9.5Cu1)0.97Nb0.03 (x = 36, 38, 40, 42, 44) alloys have been investigated systematically. It was found that the partial substitution of Fe for Ni can enhance the GFA, increasing the Trg from 0.507 to 0.527 for the best-performing alloy. With increasing annealing temperature, less α-Fe(Si), and more (Fe,Ni)Si and (Fe,Ni)B phase precipitates. The crystallization kinetics show that the peak temperature of the secondary phase transformation (α-Fe(Si)→γ(Fe,Ni)Si) is less sensitive to the heating rate. It is also found that structural relaxation of the amorphous system and consequential release of internal stress results in a decrease in Hc and an increase in µe. The minimum Hc values and maximum µe values for the alloys with x = 36, 38, 40, 42, and 44 were 0.14 A/m, 0.11 A/m, 0.23 A/m, 0.08 A/m, and 0.03 A/m, and 17,000, 14,600, 10,800, 12,700, and 16,500, respectively.

Investigation into the Structural, Spectral, Magnetic, and Electrical Properties of Cobalt-Substituted Strontium W-Type Hexaferrites

The solid-state reaction method is used to synthesize W-type Sr hexagonal ferrites Sr0.8Pr0.2(Zn1.0−xCox)2Fe16O27 (x = 0.00, 0.15, 0.30, 0.45, 0.60, 0.75). The results of XRD for the W-type hexagonal ferrites, when Co content (x) is 0.00 ≤ x ≤ 0.75, exhibit that they are in the single W-type hexaferrite phase. As shown by morphological analysis, the particles are hexagonal-shaped platelets. The saturation magnetization (Ms) and magneton number (nB) increases with Co content (x) from 0.00 to 0.60. Ms and nB begins to decrease at Co content (x) ≥ 0.60. With increasing Co content (x) from 0.00 to 0.75, the magnetic anisotropy field (Ha), first anisotropy constant (K1), and coercivity (Hc) decrease gradually. The values of DC electrical resistivity for W-type hexagonal ferrites Sr0.8Pr0.2(Zn1.0−xCox)2Fe16O27 (0.00 ≤ x ≤ 0.75) are in the range of 20.854 × 107 Ω-cm and 22.755 × 107 Ω-cm.

Effects of compression ratio, blending ratio and engine speed on fuel cost, performance and exhaust emissions of a diesel engine fueled with bio-derived alternative fuels

There are numerous studies on the effects of biodiesel-diesel fuel blends on the performance and emission characteristics of diesel engines at constant engine speeds and/or constant compression ratios. However, there is lack of studies on the investigation of the combined effects of engine speed, compression ratio and biodiesel content on both performance and exhaust emissions as well as fuel cost. Thislackhasmotivatedthe present study. Corn oil biodiesel (methyl ester) was produced by the transesterification method. Performance and emission characteristics of a single-cylinder water cooled diesel engine fueled with blends of diesel fuel (DF) and corn oil biodiesel were investigated by changing engine speed (1000–1600 rpm) at each compression ratio (ε = 17, 19 and 21). The test fuels were prepared on volume basis by the blending method and named B20, B40, and B60. Economic analysis was performed for each test fuel at different engine speeds and compression ratios. Firstly, it is found that the use of B20 and B40 at ε = 17 on average leads to an improvement in brake effective power, brake specific energy consumption and brake effective efficiency, compared to DF. However, on average, the use of B20, B40 and B60 at ε = 19 and 21 causes a decrease in brake effective power (by 6.5026 %) and brake effective efficiency (by 8.4650 %) while an increase in brake specific fuel consumption (by 18.2373 %) and brake specific energy consumption (by 9.4340 %), compared to DF. At each compression ratio, the biodiesel-diesel fuel blends producelower CO, HC and smoke but higher CO2and NOx emissions. As compression ratio is increased,brake effective power, brake effective efficiency, NOXand CO2increase while brake specific fuel consumption, brake specific energy consumption, CO, HC and smoke decrease for all test fuels. Moreover, the biodiesel-diesel fuel blends increasefuel cost in the range of 51.2862 %-213.8935 % on average, compared to DF. Finally, it is concluded that the increasing compression ratio is an effective method to reduce emissions and to improve performance.

A prototype method to evaluate the inner wall defects of ferromagnetic materials based on a two-stage magnetic combined detection

As the ferromagnetic materials have been more and more widely used in engineering, the detection requirements of the inner wall defects on structural components such as pressure vessels and pipes become urgent. Under the effect of high temperature, high pressure and corrosive media, the inner wall defects of ferromagnetic materials including crack, pore and corrosion tend to appear. In order to improve the detection efficiency, it is wise to evaluate the inner wall defects from the outside of ferromagnetic materials in a nondestructive way. Considering the rapid detection capability of metal magnetic memory (MMM) and the high sensitivity of magnetic needle probe (MNP), we combine these two magnetic nondestructive testing (NDT) techniques together and use them at two different detection stages, respectively, to help to better evaluate the inner wall defects of ferromagnetic materials. During the first stage of MMM detection, the weak magnetic signals measured from the outside of samples show that both the amplitude of MMM signal tangential component HP(x) and the gradient of MMM signal normal component HP(y) change obviously at the location of inner wall defect. However, they cannot quantify the size of inner wall defect at the backside of samples due to the serious fluctuation of signal characteristics under the interference of environment. Next, during the second stage of MNP detection, the hysteresis loop obtained by MNP can be used to quantitative evaluation because the remanence Br and the coercivity Hc decrease sharply near the inner wall defect. Furthermore, the overall average values of remanence Br¯ and coercivity Hc¯ are proposed as the characteristic thresholds to accurately determine the location and the size of inner wall defect and the evaluation accuracy can reach up to 90%. In this paper, the two-stage MMM and MNP combined detection can provide a convenient and accurate prototype method to evaluate the inner wall defects of ferromagnetic materials from the outside.

Influence of Palm Oil Biodiesel Blend Preheating on Performance Parameters, Emissions and Combustion Characteristics in a Stationary Diesel Engine

This research evaluates the effect of preheating in different blends of palm oil biodiesel in a stationary diesel engine. For the research development, the characteristics of performance, emissions (CO, CO2, NOx, HC, and smoke opacity), combustion chamber pressure, and heat release rates are evaluated. Experimental tests were conducted at three load conditions (50%, 75%, and 100%) and three biodiesel blends (BP5%, BP10%, and BP15%). To study the effect of preheating, a fuel injection temperature of 30 °C to 70 °C was set. The results obtained show a 6.40% increase in BSFC and a 4.41% reduction in engine BTE when running with biodiesel blends. However, preheating in biodiesel blends led to lower BSFC and higher BTE by 2.08% and 2.12%. The preheating of palm oil biodiesel (BP5%, BP10%, and BP15%) favored the decrease in CO, HC, and engine smoke opacity emission levels by 29%, 37.31%, and 7.84%. The additional presence of oxygen molecules and the increase in fuel injection temperature contribute to the formation of NOx emissions. The increase in injection temperature causes an increase in peak combustion pressure levels and heat release rate by 2.53% and 2.41%. In general, preheating palm oil biodiesel is a promising strategy to minimize the negative effects caused by the high density and viscosity of this type of fuel.

High sensitivity of nickel doping upon magnetism in the ″114″ magnetoelectric CaBaCo4O7

Here, we report a systematic investigation in the sensitivity of tiny Ni-doping on magnetic properties of magnetoelectric CaBaCo4O7. Interestingly, just 0.5% Ni-doping results in noticeable change in the magnetic properties of CaBaCo4-xNixO7 (0 ≤ x ≤ 0.07). The ferrimagnetic state of CaBaCo4O7 is drastically suppressed above 1% Ni-doping. This result suggests high sensitivity of Ni-doping on magnetic properties of CaBaCo4O7. We have compared our observation with reported non-magnetic and magnetic doping in CaBaCo4O7 and provided a plausible explanation of exceptional sensitivity of Ni-doping. We observed a decrease in ferrimagnetic TC and coercive field HC along with a dramatic suppression of remanent magnetization Mr in CaBaCo4-xNixO7 (0 ≤ x ≤ 0.07). Ni-doping results in competing magnetic interaction between ferrimagnetic and antiferromagnetic phases. Unlike, the nonmagnetic doping replacement of Co2+ by magnetic Ni2+ in the ferromagnetic chain in kagome layer induces antiferromagnetic exchange with the adjacent cobalt spins following Goodenough-Kanamori rules. This results in reorientation of spin that modifies the ferrimagnetic ground state resulting in competing magnetic states. Ni substitution leads to disorder and disturbs the exchange interactions which could be responsible for competing magnetic state and broadening of magnetic transition in the doped samples.

Experimental evaluation of hydrogen enrichment in a dual-fueled CRDI diesel engine

The influence of hydrogen enrichment on the dieselengine fueled with diesel and palm biodiesel blend (P20) is investigated in this study. The hydrogen is injected into the intake manifold at different flow rates of 7 lpm and 10 lpm for each loading condition of 30%, 60%, 80%, 90%, and 100%, respectively. Hydrogen enrichment improves the BTE and BSEC due to its high calorific value and decreases emissions like HC, CO, and CO 2 due to its carbon-free structure. However, due to a rise in EGT, NO x emission has increased. With the addition of hydrogen, combustion properties such as in-cylinder pressure (ICP), heat release rate (HRR), and ignition delay (ID) improve while the combustion duration (CD) drops. Compared to P20 fuel,P20 + 10H 2 has a 28% increase in BTE and a 20% decrease in BSEC at 90% load. Similarly, HC, CO, and CO 2 emissions decrease by 16%, 35%, and 12%, while NO x emission increases by 13% compared to P20. At full load, P20 + 10H 2 increasesin-cylinder pressureand heat release ratebyupto 1–5%, while CD decreases by 12.5% compared to the P20 blend. • Locally available Palm oil is used to produce biodiesel. • Hydrogen is introduced at the rate of 7 lpm and 10 lpm with both diesel and biodiesel. • Hydrogen enrichment improves BTE and BSEC by 28% and 20%, respectively. • Higher peak pressure and HRR is obtained with the induction of hydrogen. • Decrease in CO, HC, and increase in NO x emissions by 35%, 16%, and 13% are observed.

Comparisons of Cocoa Pod Husks and other Biomass Wastes for Syngas Production

In this study, the characteristics of sawdust, switch grass, cocoa pod husks, and bagasse were investigated and compared, as well as the effects of blended nickel and silicon dioxide catalysts on syngas production by gasification utilising a fluidised bed reactor. Because of their high volatile matter and cellulose content as well as low moisture content, sawdust, switch grass, cocoa pod husks, and bagasse were found to be appropriate for generating syngas. Experimental analysis was conducted on the sawdust, switch grass, cocoa pod husks and bagasse samples with and without catalyst. The grains in the samples were comparable in size, ranging from 2mm to 6mm. The catalysts were revealed to have a distinct influence on the gasification process. The efficiency of the processes improves with catalysts, while the generation of CO, CO2, HC, and NO decreases. Cocoa pod husks produced the highest HC value of 7928 ppm without catalysts while bagasse produced 1679 ppm that is the lowest HC value.

A study of oxygen-enriched reactivity-controlled compression ignition combustion in a diesel research engine under varying loadings and premixed ratios

ABSTRACT High-Efficiency Reactivity-Controlled Compression Ignition (RCCI) with ultra-low NOx and Soot emissions still needs to be investigated in terms of its operating conditions such as high load range and increasing CO and unburnt HC emissions, which are critical issues to be addressed before implementation for practical engines. Therefore, as the main factors affecting the RCCI combustion are the engine load and premixed ratio of low reactivity-fuel, in the present study, the effect of these parameters in a modified single-cylinder research engine equipped with common-rail direct injection (CRDI) on RCCI combustion are experimentally studied in detail along with oxygen-enrichment environment at two stages. At first, the effect of engine load (20%, 40%, and 60% of max.torque at 2400 rpm) and premixed ratio (Rp, 15% to 60% in increments of 15%) in enriched O2 environment to 29% was investigated while in second stage, increasing oxygen amount in intake air under low-mid load range (40% of max.torque) and premixed ratio (Rp, 30% replacement of total energy given to engine) was investigated, and compared with atmospheric air conditions. Following results were noted in the first part of the study when the engine load was increased at all premixed ratios; in-cylinder pressure and rate of heat release increased with shortening the ignition delay, IMEP increased up to 12% along with decrease in CO (by 38%), unburned HC (by 32%) and smoke opacity (by 24%) with the cost of increasing NOx emissions by 162% when compared to atmospheric air. In the second stage, increase in oxygen ratio resulted in decrease of ignition delay period and prolong combustion duration that have led to RCCI engine performance to be better and sharp reductions in the incomplete combustion emissions up to 36%. It was concluded that enriched oxygen is a beneficial way for reducing exhaust emissions during RCCI combustion at wider operating conditions.

Influence of iron oxide nanoparticles with different injection pressures using lotus seed methyl ester biodiesel: an experimental investigation

ABSTRACT The present research work explores the utilization of lotus seed methyl ester in a Common rail direct injection diesel engine. It evaluates the performance, combustion aspects, emission features at different injection pressures 210 bar to 240 bar intervals of 10 bar, along with 120 ppm of iron oxide nanoparticle. For this investigation, the B20 blend used as fuel contains 80% diesel and 20% biodiesel (Lotus seed Methyl Ester). The iron oxide nanoparticles were mixed with the fuel using a mechanical homogenizer and ultrasonication. The present work results revealed a reduction in FC by 12.5%, decreased CO by 50%, a decrease in HC by 16.88%, and the reduction of smoke density by 16.51% compared to that of baseline fuel maximum load (5.2 kW). The combined effect of 240 bar injection pressure and 120 ppm of iron oxide nanoparticle gives the best result. Abbreviation: MS; Motor Sprit (Petrol): HSD; High Speed Diesel: AFT; Transportation fuels: ICRA; Investment Information and Credit Rating Agency of India Limited: IONP; Iron Oxide Nano Particles: SFC; Specific Fuel Consumption: LSME; Lotus Seed Methyl Ester: MT; Metric Ton: BTE; Brake Thermal Efficiency: HC; Hydrocarbon: CO; Carbon monoxide: NOx; Nitrogen Oxides: HRR; Rate of Heat Release: BP; Brake Power

Effect of post-annealing on microstructural and magnetic properties of CoFe2O4:MgO nanocomposite films on MgAl2O4(0 0 1) substrates

Heteroepitaxial CoFe2O4:MgO nanocomposite films were grown on single-crystalline MgAl2O4(001) substrates by the pulsed laser deposition technique. The effect of post-annealing on microstructural and magnetic properties of the nanocomposite films has been systematically investigated. In the heterosystems, misfit dislocations bounding anti-phase domain boundaries release the epitaxial strain between the nanocomposite films and the substrates. Compared with the as-grown films, the Co distribution and the epitaxial strain state change in the post-annealed nanocomposite films. Additionally, the in-plane saturation magnetization (Ms) and coercivity (Hc) decrease, while Ms decreases but Hc increases along the out-of-plane direction of the post-annealed nanocomposite films. Our findings indicate that a feasible strategy to change the physical properties of the single-phase film by post-annealing can be applied to the nanocomposite films containing spinel ferrites.

Development of Ferromagnetic Materials Containing Co2P, Fe2P Phases from Organometallic Dendrimers Precursors.

The development of synthesis methods to access advanced materials, such as magnetic materials that combine multimetallic phosphide phases, remains a worthy research challenge. The most widely used strategies for the synthesis of magnetic transition metal phosphides (TMPs) are organometallic approaches. In this study, Fe-containing homometallic dendrimers and Fe/Co-containing heterometallic dendrimers were used to synthesize magnetic materials containing multimetallic phosphide phases. The crystalline nature of the nearly aggregated particles was indicated for both designed magnetic samples. In contrast to heterometallic samples, homometallic samples showed dendritic effects on their magnetic properties. Specifically, saturation magnetization (Ms) and coercivity (Hc) decrease as dendritic generation increases. Incorporating cobalt into the homometallic dendrimers to prepare the heterometallic dendrimers markedly increases the magnetic properties of the magnetic materials from 60 to 75 emu/g. Ferromagnetism in homometallic and heterometallic particles shows different responses to temperature changes. For example, heterometallic samples were less sensitive to temperature changes due to the presence of Co2P in contrast to the homometallic ones, which show an abrupt change in their slopes at a temperature close to 209 K, which appears to be related to the Fe2P ratios. This study presents dendrimers as a new type of precursor for the assembly of magnetic materials containing a mixture of iron- and cobalt-phosphides phases with tunable magnetism, and provides an opportunity to understand magnetism in such materials.

Effect of ternary fuel blends on performance and emission characteristics of single cylinder diesel engine

The higher alcohol such as hexanol was added at various concentrations with diesel in this current research work while retaining the neem biodiesel at 20% concentration to form the ternary fuel blend. In a single cylinder diesel engine, three distinct ternary blends (B20HB10, B20HB20, B20HB30) were taken and all the blends were tested and the results were contrasted with a binary blend (D80:B20, namely B20) and pure diesel fuel. The experiment showed that when the alcohol concentration rises from 10 % to 30 % because of the decrease in calorific value, the brake thermal efficiency decreases slightly. In addition, owing to the availability of intrinsic oxygen in it, all the ternary blend contributes to a decrease in HC and CO emissions, which leads to more complete combustion. It was also found that there was a substantial reduction in NOx emissions for all ternary blend due to the high latent heat of vaporization.

Studies on the performance and exhaust emission characteristics of a plastic oil fueled CRDI engine with variable compression ratio

In the modern days, the entire world is experiencing the sudden rise in energy needs. Strict emission rules and exhaust of oil reserves have led the scientists around the world to look into different fuels for IC engines. On other context, plastic wastes are currently the biggest problem across the globe for their indispensable nature and the alarming increase in the use of plastic for industrial applications. In this context, plastic oil has been considered as an alternative to the fossil fuels, as the properties of the oil extracted from waste Polyethylene are at par with those of diesel. Literature review reveals the fact that automobile sector ranks highest in polluting the environment through the emission of CO, CO2, NOx and unburnt hydrocarbon. In the present work, an investigation has been carried out to convert the waste plastic into a combustible oil and use of this oil blended with diesel to run a 4- stroke, 3.5kW, single cylinder, CRDI engine. Plastic oil has been prepared by pyrolysis process and subjected to fractional distillation. A blend consisting of 10% of this oil and 90% of diesel has been used as the fuel to run the engine at three different compression ratios. The performance and emission characteristics of the engine have been analyzed and reported. The results reveal a marginal increase in BTE, CO2, NOx and decrease in BSFC, CO, HC and smoke emissions.

Evaluation of biodiesel on speciated PM2.5, organic compound, ultrafine particle and gaseous emissions from a low-speed EPA Tier II marine diesel engine coupled with DPF, DEP and SCR filter at various loads

Most of marine vessels spent longer time during shipping because their routes are not closer to seashore, and emit a wide range of pollutants. These significantly contributes to regional and global pollutant inventories of fine particles (PM2.5) and gaseous emissions, which affects the local air quality. For this, the present work aimed to investigates the effect of biodiesel-diesel oil (B0, B25, and B50) ratios on regulated emissions from EPA Tier II marine propulsion engine at different loads. Experiments were carried out at low engine speed and the corresponding observations were recorded on idling in gear and loads in the ISO 8178–4 E3 duty cycle. PM2.5 emission factors for elemental and organic carbons (EC and OC), organic and inorganic species, gaseous emissions and particle size distribution were also determined. Results showed that EC, OC and rate of aliphatic compounds to polycyclic aromatic hydrocarbons (PAHs) were decrease with increase in loads. At 25% and high loads, much significant decrease in HC and CO emissions were observed with B50, whereas higher NOx emissions were acquired across all biodiesel blend fuels. This was due to the occurrence of bonded oxygen with the absence of aromatics in the biofuels. The size distribution of particles emitted from B25 and B50 evident significant number of ultrafine nuclei at 25% and 50% as compared to other engine loads. With an increase in biodiesel fuel, emissions of metals trace in the fuel were embraced with other metal oxides catalyst to develop multi-metal oxide catalyst. This enhance the catalyst activity to withstand poisoning and improve thermal stability. The emission results were within the EPA certification norms and across biodiesel ratios.

Study on combustion control of a methanol SICI engine

Spark induced compression ignition (SICI) combined mode combustion can effectively solve the problems existing in homogeneous charge compression ignition (HCCI) combustion, and expand its operation range. The SICI combined combustion of methanol is divided into two combustion stages and has the characteristics of spark ignition (SI) and compression ignition (CI) combustion modes at the same time. This paper studies the SICI combustion mode of methanol from two aspects: simulation and experiment. The simulation results show that with the increase of the wall temperature, it indirectly affected the SICI combined mode combustion by affecting the hot atmosphere in the cylinder, which shortened the whole combustion duration, the SI and CI duration, it had little effect on the combustion ratio of SI and CI. The bench test results show that the methanol engine can obtain stable SICI combined mode combustion mode under the conditions of appropriate intake temperature and suitable ignition timing. From the comparison of three combustion modes of methanol, the results show that the cyclic variability of SICI combustion is the smallest. With the increase of inlet air temperature and the delay of ignition, the BP of SICI combustion at methanol starting point moves backward, the CI combustion rate decreases, but the SI combustion duration changes slightly, and the compression ignition ratio decreases. In the SICI combustion mode of methanol engine, with the increase of intake temperature, NOx emission increases, HC and CO emission decreases. With the advance of ignition timing, CO emission decreases, HC and NOx emission increases.