Standard Diesel Research Articles

Experimental Comparison of Diesel and Crude Rapeseed Oil Combustion in a Swirl Burner

In pursuing maximum energy efficiency, local utilization of various crude fuels came into view. The present paper compares the combustion characteristics of standard diesel oil and crude rapeseed oil; the latter is an excellent model for high-viscosity liquid fuels. The combustion tests were performed in a 15 kW atmospheric turbulent swirl burner; the liquid fuels were atomized by a plain-jet airblast atomizer. Firstly, the acoustic signal is evaluated, since the instabilities of swirl combustion are accompanied by characteristic pressure fluctuations. The spectral analysis was performed by Wavelet transform, which fits excellently to the acoustic spectrum of combustion noise. This multi-scale technique features increased spectral resolution at lower frequencies at the expense of lower temporal resolution, providing excellent performance at both low-frequency, well-localized components and high-frequency, broadband phenomena. The joint probability density function of two characteristic frequencies was plotted with the result that flame acoustics match for the two fuels. Secondly, their pollutant emissions were compared and evaluated under similar conditions with the conclusion that crude rapeseed oil can substitute diesel oil in a limited operating range. Note that the distinct material properties already mean differences in all atomization, evaporation, and mixing characteristics, hence, the latter result is not intuitive.

Experimental investigation on the combustion, performance and exhaust emission characteristics of poppy oil biodiesel-diesel dual fuel combustion in a CI engine

In this study, a single cylinder, four-stroke, naturally aspirated with compression ratio of 18:1 direct injection diesel engine was run with opium poppy oil biodiesel-diesel fuel blends. The effects of diesel and biodiesel-diesel fuel blends were investigated experimentally on combustion, performance and emissions. Experiments were conducted with standard diesel fuel and opium poppy oil biodiesel-diesel fuel blends (OP10 and OP20) at maximum brake torque speed of 2200 rpm and five different engine load including 25%, 50%, 75% and 100%. This study focuses on the detailed performance and combustion analysis with opium poppy biodiesel under different engine load and speeds. Test results showed that in-cylinder presssure and heat release rate increased with the increase of engine load when biodiesel fuel blends were used. ID period increased with the usage of biodiesel. Thermal efficiency decreased by about 5.73% and 13.05% with OP10 and OP20 compared to diesel respectively owing to lower calorific value of opium poppy oil biodiesel at 75% engine load. NOx increased 2.9% and 5.98% with OP10 and OP20 according to diesel at full load. On the contrary, CO decreased 14% and 17.42% with OP10 and OP20 compared to diesel at full load.

Effect of pilot and post fueling on the combustion and emission characteristics of a light-duty diesel engine powered with diesel and waste cooking biodiesel blend

ABSTRACT Biodiesel produced from waste resources provides both environmental and economic benefits. The use of biodiesel blends in tandem with advanced fuel injection strategies enables effective control over engine-out emissions. The current study investigates the effect of the pilot and post fuel injection on combustion and emission characteristics of a light-duty diesel engine fueled with standard diesel and waste cooking biodiesel blend. The engine adopted for this study is an automotive common rail direct injection (CRDI) diesel engine, wherein the electronically controlled fuel injection system provides flexibility to control single and multiple injection schedules along with the provision for change in fuel injection pressure. A blend of 80% diesel and 20% waste cooking biodiesel (B20) was tested at four-part loads and three fuel injection pressures. The test results indicated a considerable reduction in smoke (84.4%), hydrocarbon (71.8%), and carbon monoxide (46.8%), compared to the base diesel (D100) operating at a single injection and lower fuel injection pressure. Also, Brake thermal efficiency was improved by 4.46%. However, nitric oxide emission was found to be 15% higher due to the higher fuel injection pressure. The experimental results affirm that the usage of pilot and post-injection along with higher fuel injection pressure for waste cooking biodiesel blend yielded a significant reduction in emissions at part-load condition.

An assessment on production and engine characterization of a novel environment-friendly fuel

An organized approach has been made in this research to assess the diesel enginebehaviourby fuelling novel biofuel. The unique and non-toxic, renewable citronella biofuelis extractedby steam distillation process. Moreover, extracted citronella oil exhibits similar viscosity to diesel. In this analysis, gas chromatography-mass spectrograph (GC–MS) and Fourier infrared (FT-IR) techniques were employed tocharacterizethe chemical composition of citronella oil. The test fuel was prepared by mixing several blend ratios of citronellaoil, whichhas been intermixed with diesel by volume basis, namely B20, B40, and B60. Its properties were appraised according to material standards. The test fuels were examined on a mono-cylinder conventional diesel engine. From the experimental exploration, it has been observed that citronella oil can succeed up to 20% at the top load condition in that order. Appreciably,the tailpipe Smoke emissionhas been reducedby 31% thana standard diesel operating mode, with a minor increase in oxides of nitrogen (NOX) and carbon dioxide (CO2) emission by 12.5% and 7.1%. Besides that, carbon monoxide (CO) andhydrocarbon (HC) are 16.34% and 22.2% lesser than regular diesel fuel mode at the peak load condition. The BTE of citronella oil, along with its blend, exhibits minimal values when correlated with diesel fuel along with several combinations B20 blend, had better efficiency. The B20 (20% Citronella oil + 80% Diesel) claimed 1.47% lower in engine BTE and 2.7% higher fuel consumption than a diesel engine. The combustion analysis reported that citronella fuel had significant improvement in-cylinder pressure (CP), exhaust gas temperature (EGT), and heat release rate (HRR) with considerable reduction in ignition delay (ID).

Char-diesel slurry fuels for microgeneration: Emission characteristics and engine performance

Abstract Diesel engine generators are one of the major methods for off-grid and on-demand electricity generation, particularly in the remote areas of some developing countries. However, access to fossil diesel is often limited by supply or price. In many regions, biomass is an abundant source of energy, but many types are not suitable for producing traditional liquid biofuels such as biodiesel. This paper explores the use of so called ‘slurry fuels’ produced by the blending of micron sized particles of carbonaceous material in diesel and assesses whether these ‘slurry fuels’ can be used in a standard diesel engine generator with minimal modification. Two types of micronized carbon chars were added to diesel, produced by either pyrolysis or hydrothermal carbonization of biomass. The results indicated that at high engine power, the micronized carbon slurry fuels can be run at a similar efficiency as pure diesel. The major issues identified included high engine wear and the blockage of the fuel injector. Hydrothermal carbonization was found to be the best thermal conversion route for producing micronized carbon in terms of emissions when blended with diesel.

High-pressure direct injection of methanol and pilot diesel: A non-premixed dual-fuel engine concept

In order to reduce the climate impacts, methanol produced from carbon-neutral methods plays an important role. Due to its oxygen content and high latent heat, methanol combustion can achieve low soot and NOx emissions. In the present study, direct injection (DI) of methanol is investigated in a non-premixed dual-fuel (DF) setup with diesel pilot. The present DF engine study is carried out via a specially-designed new cylinder head operating with a centrally located methanol injector and with an off-centered diesel pilot injector. The target is to inject methanol close to top dead center (TDC) in a similar fashion as in standard diesel combustion enabling robust operation with high efficiency. The ignition of the DI methanol is achieved with an almost simultaneously injected diesel pilot. The experiments were conducted in a single-cylinder heavy-duty research engine at a constant engine speed of 1500 rpm with a compression ratio of 16.5. The indicated mean effective pressure (IMEP) varied between 4.2 and 13.8 bar while the methanol substitution ratio was swept between 45 and 95%. In addition, the diesel pilot and methanol injection timings were varied for optimum efficiency and emissions. The introduced non-premixed DF concept using methanol as the main fuel showed robust ignition characteristics, stable combustion, and low CO and HC emissions. The results indicate that increasing both the load and the methanol substitution ratio can increase the thermal efficiency and the stability of combustion (lower COV) together with decreased CO and HC emissions.

Data on combustion chamber measurements of a diesel engine fuelled with biodiesel of jatropha curcas and fatty acid distillates.

Data in this paper covers in-cylinder pressure and volume, crank angle degrees as time magnitude, first derivate of in-cylinder pressure, admission pressure and injection pressure in a diesel engine fuelled with biodiesel. This data brings additional information such as ignition delay and rate of heat released. As condensed information, some graphs were obtained and are into the database such as in-cylinder vs. CAD, first derivate of in-cylinder pressure vs. CAD and ROHR vs. CAD. The data shows the measurements of the cylinder pressure behaviour of biodiesel from two different sources, which are both of interest of bioenergy industry at local scenarios (Jatropha curcas and Fatty Acid Distillates). Data in the paper are shown in Tables and Graphs. Through this data, a more accurate approach to engines performance and combustion can be reach, enhancing combustion efficiency and understanding of differences with standard diesel fuel.

Optimization and modelling of mahua oil biodiesel using RSM and genetic algorithm techniques

In this present investigation, four important process parameters of catalyst concentration, molar ratio, reaction time, and reaction temperature were studied and optimized using Box Behnken assisted response surface method (RSM) and Genetic Algorithm (GA) to achieve the maximum mahua oil biodiesel yield. For this purpose, 27 experiments were conducted randomly based on the design matrix using statistical software MiniTab®2019. A maximum yield of 91.32 % is achieved in RSM, catalyst concentration and reaction time are identified as influence parameters in biodiesel yield. GA modelling show an improvement of 4.96 % in biodiesel yield compared to RSM approach. Both techniques are successfully tested in prediction and modelling the biodiesel yield from mahua oil. The obtained biodiesel from the transesterification process is blended with standard diesel fuel at various proportions (B10 to B90) and tested for different fuel properties. All the biodiesel blends are observed within the limits of international standards of ASTMD-6751 and EN-14214. The results indicate that the chosen models are highly accurate in achieving maximum biodiesel yield and mahua biodiesel is recommended as the best alternative fuel to diesel engines without any major modifications in the engine design.

Evaluation of performance and emission characteristics of a diesel engine using split injection

Society at large today is deeply concerned with environmental pollution which is primarily contributed by vehicular pollution. Diesel engines are mainly responsible for creating much of the air pollution. A large number of analyses have revealed numerous fuel alternatives with a view to mitigate emission, specially NOx and soot, and improve engine performance. This paper offers to explore the adequate balance between NOx and soot along with performance. The combined effect of split injection and piston bowl geometry on engine performance and emission has been investigated numerically. Numerical simulations were performed using three-dimensional AVL-FIRE commercial code on a single-cylinder DI Diesel engine taking standard diesel as fuel. Six different geometrical configurations of piston bowl along with three injection ratios were considered. The piston bowl geometry is modified by varying the depth and bowl radius keeping bowl volume, compression ratio, engine speed and mass injected invariant. It was noted that mass of fuel injected as pilot injection got mixed with the air, and the mixture became ready for burning prior to the occurrence of the main injection. In addition to this, the role of increasing the pilot injection mass up to 15% along with variation in piston bowl geometry on the in-cylinder mean pressure, temperature, rate of heat release and emission parameter is explored. Numerical data, computed for single injection, were validated against experimental results available in the literature. Further, an optimization study was undertaken for selected eighteen cases and results were evaluated for different injection ratios and piston geometries. Piston bowl geometry having 100 mm diameter and 2.48 mm depth and mass of fuel injected 5% in pilot and 95% in main injection (Case D4R1) was found to have optimum NOx and soot emission. The optimum NOx and soot were found to reduce by 10% and 16% by volume, respectively, as compared to those with single injection.

Assessing the biofuel – transport nexus. The case of the sugar industry in Cuba

Cuba currently faces a limited availability of transportation to support the development needs of the country. Transport availability is mostly limited because of fuel shortage. Moreover, Cuba has an important production of sugarcane, with a significant potential to further increase its production. Using sugarcane-based bioethanol is a significant opportunity for sugarcane producer countries. There are different raw materials available in the sugar industry to produce bioethanol. Therefore, there are different scenarios to increase the production of sugarcane and energy cane, to increase bioethanol production. In this study, two scenarios of sugarcane and energy cane production were considered, from which there are eight possible scenarios of bioethanol production. These bioethanol production scenarios were matched with three transport scenarios, including a business-as-usual scenario, a scenario considering the use of bioethanol blends in standard gasoline and diesel engines, and the and introduction of vehicles running on high ethanol blends or pure bioethanol (i.e flexible fuel vehicles, and ethanol buses and trucks). In total, the production of sugarcane-based bioethanol might support from 4 to 58% of the yearly demand for transport energy in the transport scenarios. Additionally, the use of bioethanol as a transport fuel can potentially reduce transport-related greenhouse gas emissions by an estimated 3–30%.

Ultra-low emission combustion of diesel-coconut biodiesel fuels by a mixture temperature-controlled combustion mode

Liquid fuels are likely to remain the main energy source in long-range transportation and aviation for several decades. To reduce our dependence on fossil fuels, liquid biofuels can be blended to fossil fuels – or used purely. In this paper, coconut methyl ester, standard diesel fuel (EN590:2017), and their blends were investigated in 25 V/V% steps. A novel turbulent combustion chamber was developed to facilitate combustion in a large volume that leads to ultra-low emissions. The combustion power of the swirl burner was 13.3 kW, and the air-to-fuel equivalence ratio was 1.25. Two parameters, combustion air preheating temperature and atomizing air pressure were adjusted in the range of 150–350 °C and 0.3–0.9 bar, respectively. Both straight and lifted flames were observed. The closed, atmospheric combustion chamber resulted in CO emission below 10 ppm in the majority of the cases. NO emission varied between 60 and 183 ppm at straight flame cases and decreased below 20 ppm when the flame was lifted since the combustion occurred in a large volume. This operation mode fulfills the 2015/2193/EU directive for gas combustion by 25%, which is twice as strict as liquid fuel combustion regulations. The 90% NO emission reduction was also concluded when compared to a lean premixed prevaporized burner under similar conditions. This favorable operation mode was named as Mixture Temperature-Controlled (MTC) Combustion. The chemiluminescent emission of lifted flames was also low, however, the OH* emission of straight flames was clearly observable and followed the trends of NO emission. The MTC mode may lead to significantly decreased pollutant emission of steady-operating devices like boilers, furnaces, and both aviation and industrial gas turbines, meaning an outstanding contribution to more environmentally friendly technologies.

Evaluation of engine efficiency, emissions and load range of a PPC concept engine, with higher octane and alkylate gasoline

Gasoline Compression Ignition research has shown that it can provide diesel like engine efficiency while maintaining gasoline like exhaust emissions. While research has shown that lower octane fuels might be good for that, they are also not available now. A good compromise for that would be the use of higher octane gasoline which is available in most places.For this study, experiments were performed under Partially Premixed Combustion (PPC) conditions with RON 90 gasoline, in a 2 L multi-cylinder diesel engine which complies with Euro 6 emissions standards. The aim is to evaluate the efficiency, the emissions and the achievable load in terms of minimum and maximum at three different speeds, 1200, 1800 2400 rpm and with two different RON 90 gasolines and the standard diesel engine hardware. The two fuels were a regular pump gasoline and an alkylate gasoline, which was chosen to represent a pathway to a renewable fuel. Results show that the minimum load is around 5 bar IMEPg, limited by high COV (coefficient of variation) values and high air intake temperature, while the maximum load reaches 18 bar IMEPg, limited by lambda value, pressure and mechanical limitations. While efficiency is similar between the two fuels with a brake value of around 40%, at higher loads the alkylate fuel produces higher amounts of soot while the regular gasoline has higher carbon monoxide at low loads. Finally, an energy balance comparison between the two gasolines and diesel is made, showing improved efficiency and soot emissions under PPC.

Combustion, performance, and emissions of safflower biodiesel with dimethyl ether addition in a power generator diesel engine

ABSTRACT In this study, the effect of dimethyl ether (DME) addition to diesel (ultralow sulfur diesel fuel) and biodiesel fuels on the combustion, performance, and emissions of a diesel-powered generator was investigated. For this purpose, fuel samples of the ternary blend that volumetrically composed of 10% safflower biodiesel–10% dimethyl ether–80% ultralow sulfur diesel fuel (B10DME10), the ternary blend that volumetrically composed of 25% safflower biodiesel–25% dimethyl ether–50% ultralow sulfur diesel fuel (B25DME25), the binary blend that volumetrically composed of 25% safflower biodiesel–75% ultralow sulfur diesel fuel (B10DME10) B25, and pure safflower oil biodiesel (B100) and standard ultralow sulfur diesel (D2) were prepared. The test engine was loaded by power drawing from the generator by the usage of equivalent powered electrical heating resistances. Generally, using DME with biodiesel improved the combustion properties of biodiesel blends that can be attributed to the lower viscosity of DME. The maximum cylinder pressure was obtained for B10DME10 in general and sometimes for B25DME25. When test fuels are compared, DME blends showed higher and earlier peaks of heat release compared to diesel and biodiesel blend fuels especially. It was found that combustion is more efficient from mass fuel consumption (MFC) and brake specific fuel consumption (BSFC) values in the use of DME than biodiesel. BSEC values of using DME in the blends considerably decreased that it is the proof of improved combustion and energy efficiency. The highest average efficiency values were obtained for B25DME25 as 28.3% although it has a lower calorific value than D2 due to the considerably improved combustion properties of DME, while the average efficiency values were 23.1%, 23.3%, and 20.7% for D2, B25, and B100 fuels, respectively. Highest carbon monoxide (CO) emissions were obtained in the use of pure biodiesel, while the lowest CO emissions were obtained in the use of DME. The addition of DME is seen to increase the nitrogen oxides (NOx) and CO emissions.

Designing the shape of the combustion chambers for gas engines converted on the basis of the diesel engines

This paper describes the advantages of using gas motor fuels by vehicles, in particular liquefied petroleum gas, co MPared to conventional diesel fuel. The expediency of converting the diesel-based vehicles to gas internal combustion engines with spark ignition has been substantiated. The ways to reduce the degree of compression of the diesel engines when they are converted into gas internal combustion engines with spark ignition have been analyzed. It has been shown it is expedient, in order to convert the diesel engines into gas internal combustion engines with spark ignition, to use the Otto thermodynamic cycle with a decrease in the geometric degree of compression. Techniques to increase the combustion chamber volume have been analyzed, as well as the expediency of applying each of them to reduce the compression degree of the diesel engines with different types of non-separated combustion chambers. An open combustion chamber has been substantiated and designed in the form of an inverted axisymmetric «truncated cone», which made it possible to reduce the geometric compression degree only by increasing the volume of the combustion chamber in the piston. The designed shape of the combustion chamber allows the use and refinement of standard diesel pistons instead of producing special new gas pistons. The gas internal combustion engine of model D-240-LPG has been designed and fabricated, in which the liquefied petroleum gas is fed to the inlet pipeline. The engine is equipped with a contactless electronic ignition system with a movable voltage distributor, as well as pistons with the newly designed shape of the combustion chamber. The engine has been converted based on the D-240 diesel engine. The bench testing of the model D-240-LPG diesel engine has confirmed the expediency of converting the diesel engines to gas internal combustion engines using the Otto cycle. The tests have shown that the energy and economic parameters of the gas engine with the proposed shape of a combustion chamber correspond to the parameters of modern internal combustion engines with spark ignition. The results obtained make it possible to optimize the technology of re-equipping the diesel engines with gas ICEs and thus reduce its cost

Taguchi method for investigation of the effect of TBC coatings on NiCr bond-coated diesel engine on exhaust gas emissions

The NiCr bond coated piston and valve surfaces were coated with Cr2O3, Cr2O3 + 50% Al2O3, Cr2O3 + 75% Al2O3 powders by thermal barrier coating (TBC). The influence of the coating layers on CO, CO2, HC and NOx was examined both statistically and experimentally. The statistical investigation was carried out by using Taguchi analysis. According to the experimental test results obtained at different engine speeds, the sample with the highest CO2 value was found at 2600 rpm in the Cr2O3 + 75% Al2O3 coated diesel engine and the sample with the lowest CO value was found at 2600 rpm in the Cr2O3 + 75% Al2O3 coated diesel engine. Also, the sample with the lowest NOx value was found at 1400 rpm in the standard diesel engine and the sample with the lowest HC value was found at 2600 rpm in the Cr2O3 + 75% Al2O3 coated diesel engine. Experimental results were analyzed by Taguchi optimization method according to L16 (42) orthogonal array. According to the statistical results obtained from ANOVA test, factor levels affecting the exhaust emission values best ​​were found. In general, better emission values ​​have been determined in diesel engines with bond coated ceramic layers.

The Flex-OeCoS—a Novel Optically Accessible Test Rig for the Investigation of Advanced Combustion Processes under Engine-Like Conditions

A new test rig has been designed, built and commissioned, and is now jointly pursued to facilitate experimental investigations into advanced combustion processes (i.e., dual fuel, multi-mode) under turbulent conditions at high, engine-like temperature and pressure levels. Based on a standard diesel engine block, it offers much improved optical access to the in-cylinder processes due to its separated and rotated arrangement of the compression volume and combustion chamber, respectively. A fully variable pneumatic valve train and the appropriate preconditioning of the intake air allows it to represent a wide range of engine-like in-cylinder conditions regarding pressures, temperatures and turbulence levels. The modular design of the test rig facilitates easy optimizations of the combustion chamber/cylinder head design regarding different experimental requirements. The name of the new test rig, Flex-OeCoS, denotes its Flexibility regarding Optical engine Combustion diagnostics and/or the development of corresponding Sensing devices and applications. Measurements regarding in-cylinder gas pressures, temperatures and the flow field under typical operating conditions are presented to complete the description and assessment of the new test rig.

Analysis of Fuel from LDPE Plastic

Plastics are perhaps the most important invention of mankind. Finding a solution to sustainably balance the usage to its environmental threat is now more important than ever. One possible solution, to make value added fuels by pyrolysis of waste plastics are discussed. Manufacturing of such fuels on a commercial scale can reduce the burgeoning plastic waste and meeting the ever-increasing fuel demand. A simple prototype to depict the pyrolysis and condensation process was constructed, and fuels samples from waste polythene bags and LDPE pellets obtained. Common physical and chemical parameters of the fuels were analysed with standard diesel as reference. The fuel obtained had some properties similar to that of diesel, and could easily be used as blends with diesel, without affecting its application.

Performance Analysis of Diesel Engine using Copper Oxide Nano Additive

This experimental study focuses on investigation of performance and utterance attributes of a normal diesel engine with biodiesel prepared from pongamia. This study aims to reduce the emission of nitrogen oxide by adding an oxidation inhibitor Tert-Butylhydroquinone (TBHQ). The analysis for each sample is to be carried out in compression ignition engine (standard diesel engine). The engine is tested with standard diesel, pongamia methyl ester biodiesel without any additives. Then the analysis is to be carried by adding nano additive copper oxide for about 50 ppm in the above mentioned fuels. From this the best combination is found out and test is again carried out by adding the oxidation inhibitor.

Spray, combustion, performance and emission characteristics of a common rail diesel engine fueled by fish-oil biodiesel blends

Considered as the alternative and less polluting fuel, biodiesel deriving from vegetable, animal or waste oils, potentially decreases atmospheric pollutants and greenhouse gases. This study contributes to the nuanced understanding of the effects of fish oil biodiesel fuel blends on spray, combustion, performance and emission characteristics. The purpose of this study is testing the effects of various concentrations of fish-oil biodiesel blends (B10, B20, B30) and standard diesel fuel (B0) on single cylinder common rail diesel engine at maximum brake torque speed of 1400 rpm and minimum brake fuel consumption speed of 2200 with different engine loads of 25%, 50% and 75% conditions. The results show that running engines with B30 at 75% load condition, the average values of engine powers, carbon monoxide (CO), unburned hydrocarbons (HC) and soot emissions decreased by 3.00%, 14.3%, 26.2% and 17.5%, respectively, while BSFC and NOx emissions increased by 3.4%, 5.1%, respectively compared to using B0. The result implies that despite testing with varying concentrations of fish oil, the performance and emission engine are not credibly different. Therefore, fish oil biodiesel-diesel fuel blends can be used efficiently as fuels for diesel engine without any major modification in the engines.

Application of biodiesel for 12-cylinder, supercharged military combat vehicle

During wartime and disaster management military logistics such as combat vehicles, heavy-duty trucks must be capable of any transportation fuel available in forward area. In present work potential use of biodiesel derived from Karanja and Jatropha oil was investigated for a heavy-duty military vehicle. Performance and emissions of 12 cylinders, supercharged diesel engine was evaluated using JP-8, Karanja Oil Methyl Ester (KOME) and Jatropha Oil Methyl Ester (JOME) and compared with baseline standard diesel at variable speed range. Engine performance was slightly reduced with KOME and JOME. However from emission point of view, both the biodiesels contributed to reduction in CO and HC emissions as well as smoke opacity, with penalty in NO x emissions. Reduction in exhaust sound was seen for biodiesel fuels which is of upmost important during wartime. Thus, biodiesels can be used for military combat vehicles without any modifications in existing engine configurations.