Diesel Fuel Blends Research Articles

Effects of dimethyl carbonate and 2-ethylhexyl nitrate on energy distribution, combustion and emissions in a diesel engine under different load conditions

Dimethyl carbonate (DMC)/diesel blended fuels are receiving increasing attention due to the advantages of DMC (oxygen content 53.3%) that improved the fuel-rich zone of diesel engines. However, the low cetane number (CN) of DMC/diesel dual-fuel at low loads resulted in a delayed combustion progress. Since the combustion phase had a significant effect on thermal efficiency, exergetic efficiency, energetic and exergetic losses; 2-ethylhexyl nitrate (EHN) was added to the mixed fuel as a CN improver, so that the combustion phase closed to that of diesel to ensure proper combustion characteristics of the DMC/diesel dual-fuel. In this study, a four-cylinder turbocharged diesel engine was used to study performance and emissions. Based on experiments, combustion characteristics including energy balance and exergy balance were focused, in which the EHN was added to the DMC/diesel mixture at different concentrations. The five test fuels included diesel (D100), and a mixture of 20% DMC with 80% diesel (DMC20). In addition, EHN was added to DMC20 at a ratio of 0.5%, 1%, and 2%. The results showed that EHN could shorten the ignition delay time of DMC and reduced maximum pressure rise rate (MPRR). The use of EHN improved brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC), under the same load, using 0.5% and 2% EHN, BTE increased by 0.2% and 1%, relative to DMC20, respectively. The study found that the energy efficiency and exergy efficiency were higher after adding EHN, which made up for the burning problem of DMC. Moreover, the irreversible loss reduced, and the available work and available energy increased. Thermodynamic analysis showed that DMC had better combustion performance than diesel after adding 2% EHN. In this study, the method of EHN/DMC/diesel blended fuel combining with 25% EGR was proposed and confirmed that the trade-off relationships of NOX and soot have been improved noteworthy.

Combustion and emission characteristics of a common rail diesel engine fueled with reformed diesel/palm oil/gasoline blend fuels

ABSTRACTPalm oil is the most abundant plant oil resource in the world. Through fuel reforming, properties of diesel, palm oil, and gasoline blend fuels are superior to those of diesel. With the constraint of major properties, D56Z24G20 (56% D100, 24% palm oil, and 20% gasoline by vol.) and D42Z18G40 (42% D100, 18% palm oil, and 40% gasoline by vol.) are prepared for experimental investigation and comparison with D100 (100% diesel). The combustion and emission results indicate that D56Z24G20 and D42Z18G40 release heat more concentratedly than D100 and thereby have a higher peak combustion temperature (PCT). NOx emission of D56Z24G20 and D42Z18G40 are higher than that of D100. Particle number concentrations (PNC) of D56Z24G20 and D42Z18G40 are higher than that of D100 at low and partial loads and a little lower at medium and high loads. The high PNC of D56Z24G20 and D42Z18G40 particles is mainly attributed to the high PNC of nucleation mode particles and this phenomenon can be eliminated with a 20% ratio of exhaust gas recirculation.

Numerical Investigation on Performance and Emission Characteristics of a Diesel Engine Fired With Methanol Blended Diesel Fuel

The effects of methanol and oleic acid blended diesel fuel on the performance and emissions of the diesel engine are evaluated numerically by commercial software Diesel-RK to simulate a single cylinder, naturally aspirated, direct injection, four-stroke diesel engine. The present study also resolves the problem of the immiscibility of methanol in diesel fuel, as to avoid immiscible nature an optimum percentage of oleic acid and n-butanol is added to make blends stable. The methanol blended diesel fuels are 7%, 12%, and 17% methanol in volume basis (D85M7NB1O7, D75M12NB1O12, and D65M17NB1O17). A drastic reduction in NOx emission is observed due to low combustion temperature however the PM emissions increases which can be controlled by using exhaust after-treatment techniques. The results indicate that: the brake specific fuel consumption increases and brake thermal efficiency decreases with an increase of methanol, oleic acid and n-butanol contents in the blended fuel whereas maximum heat release rate increases and exhaust temperature decreases.

Using Blended Diesel Fuels to Reduce CO2 Emissions

Using Blended Diesel Fuels to Reduce CO2 Emissions

Selection of Blends of Diesel Fuel and Advanced Biofuels Based on Their Physical and Thermochemical Properties

Current policies focus on encouraging the use of renewable energy sources in transport to reduce the contribution of this sector to global warming and air pollution. In the short-term, attention is focused on developing renewable fuels. Among them, the so-called advanced biofuels, including non-crop and waste-based biofuels, possess important benefits such as higher greenhouse gas (GHG) emission savings and the capacity not to compete with food markets. Recently, European institutions have agreed on specific targets for the new Renewable Energy Directive (2018/2001), including 14% of renewable energy in rail and road transport by 2030. To achieve this, advanced biofuels will be double-counted, and their contribution must be at least 3.5% in 2030 (with a phase-in calendar from 2020). In this work, the fuel properties of blends of regular diesel fuel with four advanced biofuels derived from different sources and production processes are examined. These biofuels are (1) biobutanol produced by microbial ABE fermentation from renewable material, (2) HVO (hydrotreated vegetable oil) derived from hydrogenation of non-edible oils, (3) biodiesel from waste free fatty acids originated in the oil refining industry, and (4) a novel biofuel that combines fatty acid methyl esters (FAME) and glycerol formal esters (FAGE), which contributes to a decrease in the excess of glycerol from current biodiesel plants. Blending ratios include 5, 10, 15, and 20% (% vol.) of biofuel, covering the range expected for biofuels in future years. Pure fuels and some higher ratios are considered as well to complete and discuss the tendencies. In the case of biodiesel and FAME/FAGE blends in diesel, ratios up to 20% meet all requirements set in current fuel quality standards. Larger blending ratios are possible for HVO blends if HVO is additivated to lubricity improvers. For biobutanol blends, the recommended blending ratio is limited to 10% or lower to avoid high water content and low cetane number.

Effect of Injection Pressure and Air–Fuel Ratio on the Self-Ignition Properties of 1-Butanol–Diesel Fuel Blends: Study Using a Constant-Volume Combustion Chamber

One of the ways to reduce the negative impact of diesel engines on the natural environment is to reduce the smoke opacity and emissions of nitrogen oxides. For this purpose, suitably programmed fue...

Measurement and Prediction of Density and Viscosity of Different Diesel-Vegetable Oil Binary Blends

Abstract Vegetable oils can be considered as an alternative or emergency fuel for diesel engine. However, vegetable oils result in operational and durability problems for the long-term operation because of being much more viscous than diesel fuel. To eliminate this drawback, blending of vegetable oils with diesel fuel or alcohol is one of the most widely used techniques. In the existing literature, many studies are available on the measurement and prediction of density and viscosity of binary blends (especially biodiesel (BD)-diesel fuel (DF) blends), although, there is still the lack of comprehensive studies in which reliable density and viscosity data are presented, new regression models are proposed and compared with other regression models for waste cooking oil (WCO)-DF binary blends. Therefore, in the present study, (1) WCO was blended with DF on the volume basis of 2, 4, 6, 8, 10, 15 and 20 %, (2) the measurements of viscosities and densities of the binary blends were performed at various temperatures (278.15–343.15 K) in accordance with DIN 53015 and ISO 4787 standards, respectively, (3) the variations of viscosity and density values of binary blends vs. temperature were evaluated, (4) the new rational and exponential models as a function of temperature were fitted to the experimental data measured by the authors and Baroutian et al. (regarded as typically different data), and finally (5) the models were also compared to Yoon et al. and linear models, previously proposed by other authors, in order to investigate their reliability. According to results, (i) the best correlation was obtained by the rational model with the lowest maximum relative errors of 2.9679 % and 3.2725 % for the viscosity data measured by the authors (WCO-DF blends) and Baroutian et al. (palm oil (PO)-DF blends), and (ii) for the density data of WCO-DF and PO-DF binary blends, the best correlation was obtained using the exponential model giving the lowest maximum relative errors of 0.0470 % and 0.0581 %, respectively.

Effect of injection timing on performance and emission characteristics of single cylinder diesel engine running on blends of diesel and waste plastic fuels

Abstract Environmental concern, increasing fossil fuel demands and depleting fossil fuel reserves have caused interests in the search for alternate fuels for internal combustion engines. Waste plastics are indispensable materials in the modern world and application in the industrial field is continually increasing. In this context, waste plastic solid is currently receiving renewed interest. the recycling of the waste plastic for renewable energy generation is receiving more attention nowadays. The present study deals with utilization of waste plastic pyrolysed oil in single cylinder diesel engine with varying injection timing. The pyrolysis of mixed waste plastic was carried out at 400oC-550oC in a fixed bed reactor. The physic chemical properties such as calorific value density, viscosity, cloud point, pour point, flash point of the plastic fuel and its blends with diesel (PF10,PF20,PF30) was analysed using standard methods and found under ASTM standards. To see the effect of injection timing on performance and emission, a single cylinder diesel engine was run on plastic fuel blends at the two different angles (10o retard and the 8o advance before the TDC). The results showed that at advanced condition BTE, CO, UHC, CO2 and smoke increased while BSFC and NOx decreased with the increasing load.

Experimental Investigation of Waste Vegetable Oil – Diesel Fuel Blends Effects on Performance of Compression Ignition Engine

In this study, energy performance of diesel engine experimentally examined with cooking oil – diesel blends (D95B5, D90B10, D85B15 and D80B20) as retrofit for pure diesel (D100). An assessment of engine performance was investigated at varying engine speeds load conditions for both pure diesel and its blends at both laboratory conditions and under British Standard (BS) conditions. Results of this investigation show that the average engine torque reduction compared to D100 for D95B5, D85B15, D90B10 and D80B20 was found as 9.03%, 10.32%, 13.95% and 23.06% and average engine power reduction was found as 7.09%, 11.48%, 12.43% and 21.12% respectively. In terms of bte, average increase in bte was found as 5.95% and 0.29% for D95B5 and D85B15 but average reduction was found as 3.17% and 9.45% for D90B10 and D80B20 fuel blends, respectively. While, D95B5 was 5.32% lower than D100. From this study, D95B5 produced better performance when compared to D85B15.

Investigation of the Effects of Linseed Oil Biodiesel and Diesel Fuel Blends on Engine Performance and Exhaust Emissions

In this study, linseed oil was obtained with the aid of screw presses and linseed oil biodiesel (B100) (linseed oil methyl ester) production was performed by transesterification method. Linseed biodiesel was blended with regular diesel fuel at different ratios as B2 (98% diesel + 2% biodiesel), B5 (95% diesel + 5% biodiesel), B20 (80% diesel + 20% biodiesel), B50 (50% diesel + 50% biodiesel). Fuel properties tests were performed on all fuels. Results revealed that engine performance values of linseed biodiesel and fuel blends were similar with the standard diesel fuel. With regard to maximum torque, while the highest value was obtained as about 59.6 Nm at 1000 rpm with diesel fuel, the value was observed as about 53.8 Nm at 1200 1/min with B100 fuels. The highest maximum power output was recorded as approximately 10.96 kW at 2100 rpm with diesel fuel and as approximately 10.23 kW at 2000 rpm with B100 fuels. With regard to minimum specific fuel consumption, while the lowest value was measured as about 231.36 g/kWh at 1000 rpm with diesel fuel, the value was measured as about 296.73 g/kWh at 1200 rpm with B100 fuels. Exhaust emissions are generally improved by the addition of linseed biodiesel to diesel fuel.

Performance and Emission Characteristics of a Diesel Engine Fueled with Alcohol–Diesel Fuel Blends Containing Low Ratio of Alcohols

The study is to investigate the effects of diesel–alcohol blends containing low ratio of alcohols on the performance and emissions of a diesel engine. Methanol, ethanol, iso‐propanol, and n‐butanol containing 5% by volume were blended with diesel fuel. Then, these blends and neat diesel fuel were tested in an electronic control high‐pressure common rail turbocharged direct injection (DI) diesel engine working at the speed of 2000 revolutions per minute (rpm) and 2800 rpm at five different loads without any modification in the original engine structure. The results of the blends tests were compared with the results of neat diesel fuel under the same condition. The results revealed that, with the increase of the carbon atom number of alcohol, peak combustion pressure of main injection, cumulative heat release, maximum combustion temperature and brake specific fuel consumption (BSFC) increased for the blends. The combustion duration for the blends became shorter than that of pure diesel. Diesel–alcohol blends containing low ratios of various alcohols can effectively reduce at least 29% of smoke emissions and under one condition the percentage can reach 81%. Additionally, the blends have a slight influence on the oxides of nitrogen (NOx) emissions. The emissions of carbon monoxide (CO) and unburnt hydrocarbon (THC) increased very slightly at low load, but they decreased distinctively at medium and high load. © 2018 American Institute of Chemical Engineers Environ Prog, 38:e13035, 2019

Emissions of automobiles fueled with alternative fuels based on engine technology: A review

Abstract Diversification of alternative fuels for automobiles is not only an actual situation, but also a development trend. Whether the alternative fuels are clean is an important issue. Emissions of automobiles fueled with natural gas (NG), methanol, ethanol, biodiesel, dimethyl ether (DME) and polyoxymethylene dimethyl ethers (PODEn) are investigated and reviewed based on engine technology and fuel properties. Compared to gasoline, NG/gasoline bi-fuel and NG automobiles have higher brake thermal efficiencies (BTE) and produce less HC, CO and PM emissions, while more NOx emission. Compared to diesel, NG/diesel dual fuel automobiles have lower BTE and emit lower soot and NOx emissions, but higher HC and CO emissions. Methanol and ethanol blending in gasoline can obviously reduce the HC, CO and PM emissions of spark ignition (SI) automobiles. Methanol or ethanol blending in diesel may prolong the ignition delay, shorten the combustion duration and improve the BTE, resulting in lower soot emissions. However, the HC, CO and NOx emissions of methanol or ethanol diesel blend fuels are uncertain due to low cetane number, high latent heat of vaporization. Most biodiesel has higher viscosity, distillation temperature, cetane number and oxygen content than diesel. Soot emission of biodiesel is lower than that of diesel, while NOx emission is higher. Both DME and PODEn do not contain C C bonds and their blend with diesel can prohibit the formation of soot. PODEn has high cetane number and low viscosity, resulting in better ignitability and spray quality respectively. PODEn blending shortens both the ignition delay and the combustion duration, improves the BTE, and increases the temperature in the diffusion combustion phase, leading to a higher NOx emission.

Analysis on Tribological Characteristics of Waste Ayurvedic Oil Biodiesel Blends using Four Ball Tribometer

Tribology related problems in an engine give challenges to the automobile sector. To minimize the issues raised by diesel fuel, the biodiesel gains a vertical attention by the researchers. Especially, the waste oils will lead a high pollutant material to the environment and it needs a proper procedure to disposal. In this present study it is aimed to investigate the friction and wear characteristics of Waste Ayurvedic Oil (WAO) biodiesel blends by varying the applied load in a four ball wear test Tribotester. The investigations of fuels were WAO biodiesel blends (B10, B15 and B20) and diesel fuel was analysed with test conditions viz: load 40Kg and 80Kg, constant temperature 75°C, duration: 300 sec, sliding speed: 1200rpm for all the tested fuels. For the given experimental conditions more wear scar diameter were observed for diesel than WAO biodiesel blends for both the loads. The coefficient of friction and frictional torque were absorbed less with WAO15 for both the loads than other blended fuels and diesel fuels. The worn surfaces of the steel balls were examined by a Scanning Electron Microscope (SEM). The morphology image results showed that minimal friction, wear and smoother surface were absorbed for all the biodiesel concentrations than the diesel fuel.

Autoignition reactivity of blends of diesel and biodiesel fuels with butanol isomers

The effect of n-butanol replacement by iso, sec or tert-butanol on the autoignition reactivity of diesel and biodiesel/butanol blends (the total alcohol content being 40% by vol.) was analysed. The study was performed in a constant volume combustion chamber under different initial temperatures (535 °C, ∼600 °C and 650 °C) and n-butanol substitutions. Results show that the effect of the alcohol in both pseudo-binary (diesel fuel/normal, sec, iso or tert-butanol) and pseudo-ternary (diesel fuel/n-butanol/iso, sec or tert-butanol) blends is not that expected from the autoignition properties of the pure isomers. When blended either with diesel or biodiesel fuels, tert-butanol increases the autoignition reactivity of the blend while the other two isomers reduce it. The partial substitution of n-butanol by tert-butanol could be an attractive method for increasing the alcohol content while keeping safe engine operation. Partial substitutions with iso or sec-butanol would promote partially premixed combustion conditions with limited pressure gradient peaks. Chemical kinetics simulations corroborate that the different consumption rates of active radicals from the butanol isomers are responsible for the observed trends. Biodiesel blends are less sensitive to the isomer replacing n-butanol due to its higher number of secondary CH bonds when compared to diesel fuel.

Effect of In-Cylinder Conditions on Spray Characteristics of Diesel, Biodiesel, and Biodiesel-Ethanol Blended Fuels

The analysis result of liquid fuel combustion performance shows that the factors affecting chamber combustion are the vaporization and atomization of liquid fuel. At the same time, the combustion chamber conditions and the property of liquid fuel, in turn, affect the heat transfer process and atomization quality. The present work aims to study the effect of in-cylinder conditions on spray characteristics of diesel, biodiesel, and biodiesel-ethanol blended fuels. Besides, research of the addition of ethanol in biodiesel blends compared with diesel is also discussed in this paper. Meanwhile, for the sake of contrastive analysis, two prediction models are adopted, and the corresponding research is conducted. With the experimental results and theoretical analysis approach, the extent and main influencing factors of droplet vaporization and breakup in the spray process are reached. The liquid-fuel penetration and spray tip penetration all present a decreasing tendency with the increase of in-cylinder pressure and percentage of ethanol in blended fuel, and these parameters are affected slightly by the change of in-cylinder temperature in certain range.

Density and Viscosity Measurements for Olive Oil Biodiesel, Diesel Fuel and n-Butyl Alcohol Ternary Blends

Density and Viscosity Measurements for Olive Oil Biodiesel, Diesel Fuel and n-Butyl Alcohol Ternary Blends

On the assessment of autoignition delay for Diesel fuel and Biodiesel B20

The use of bio-fuels is a necessity nowadays, regulated by European legislation, which imposes to the EU-countries an increase in the substitution rate of classic fossil Diesel fuel. Biodiesel (B) fuel proves to be a reliable agent to fulfil this requirement, but a certain number of aspects have to be ameliorated regarding the compatibility of this kind of fuel with the existent compression ignition engines. One of these problems relies on the autoignition delay, on which the research results are still dispersed. The paper proposes an analysis of this autoignition delay when using a compression ignition (CI) engine fuelled with Diesel fuel and with blends of Diesel and Biodiesel fuels (B20 – 20% volumetric fraction of Biodiesel), starting from several correlations given by the literature, which are based on single-cycle analysis and application of the integral Livengood-Wu method. The obtained results offer an image of the in-cylinder processes complexity and of the B20 fuel behaviour related to the tested engine operation.

Performance, Combustion Characteristics and Emission Tests of Single Cylinder Engine Running on Fusel Oil - Diesel Blended (F20) Fuel

Alcohols produced from a renewable source are amongst the important alternative fuels for internal combustion engines. Investigations on alternative fuels for compression ignition engines regarded as one of the major research areas. This paper details an experimental examination of the performance and emissions in single cylinder compression ignition engines operating with fusel oil F20 and pure diesel F0 at five engine speeds and 50% engine load. The test results indicated that the engine power and torque slightly decrease with the F20 at low speeds compared with pure diesel. Further, the in-cylinder pressure was decreased at all engine speed for F20 in comparison with pure diesel. The volumetric efficiency and fuel consumption were increased for F20 due the low heating value of fusel oil. The results showed that CO2 and CO emissions were increased because of the water content, low heating value and low cetane number for fusel oil. The maximum reduction in NOx emissions was 18% for F20 at 1500 rpm.

Reactive Oxidative Species and Speciated Particulate Light-Duty Engine Emissions from Diesel and Biodiesel Fuel Blends

It is well established that particulate matter (PM) continues to be a major air pollutant challenge for human health globally, and vehicle exhaust PM emissions have been linked to many adverse health effects. However, the relative toxicity of biodiesel emissions compared to petroleum diesel remains unclear. Given the legislated mandates to increase biodiesel fuel use in response to energy security and climate concerns, in this study we examined the relationships between biodiesel fuel blend, exhaust particle oxidative potential (OP), and PM composition. Mechanistically, there is a growing consensus that the formation of reactive oxygen species (ROS) due to PM exposure leads to subsequent oxidative stress and inflammation at the cellular level. Here, dithiothreitol (DTT) assays were performed on impinger samples of PM obtained from light-duty diesel engine transient cycle emission tests with two biodiesel feedstocks, soybean (SOY) and waste vegetable oil (WVO), blended with ultralow sulfur petrodiesel at f...

Impact of gasoline and Diesel blends on combustion noise and pollutant emissions in Premixed Charge Compression Ignition engines

Research efforts in the automotive sector focus on developing new combustion concepts for mitigating the emissions of nitrous oxides and soot of conventional Diesel combustion. One of the most promising concept is the Premixed Charge Compression Ignition. In this, the fuel burns in premixed conditions, avoiding the formation of soot whereas nitrous oxides are controlled using large amounts of exhaust gas recirculation. Because of the premixed combustion, high fuel-burning velocities are produced, whence combustion noise is deteriorated. In order to mitigate this drawback, different blends of gasoline and Diesel fuels are being considered due to their suitability for this combustion characteristics. The effect of these fuel blends on emissions, performance and engine noise is analysed in this paper with the aim to provide additional knowledge of the fundamental issues of this particular combustion mode. The study also includes sweeps of both the start of injection and the amount of exhaust gas recirculation, in order to evaluate further degrees of freedom in the optimisation of the engine settings. Results show that the consideration of the engine noise together with both performance and emissions, reduces dramatically the margin of variation of the combustion settings, limiting therefore the operation range of the engine.