Direct Injection Diesel Research Articles

Fuel efficiency improvement of a dual-fuel engine fuelled with Honge oil methyl ester (HOME)–bioethanol and producer gas

Renewable and alternative fuels have numerous advantages compared with fossil fuels as they are renewable and biodegradable and provide food and energy security and foreign exchange savings besides addressing environmental concerns and socio-economic issues (Yaliwal et al. 2013. International Journal of Sustainable Engineering, doi:10.1080/19397038.2013.801530. Zhu et al. 2011a, Applied Thermal Engineering 31 (14–15): 2271–2278; Zhu et al. 2011b, Fuel 90: 1743-1750; Banapurmath, Tewari, and Hosmath 2008, Renewable Energy 33: 2007-2018; Banapurmath 2009, “Performance, Combustion and Emission Characteristics of a Single Cylinder Direct Injection CI Engine Operated on Dual Fuel Mode Using Honge Oil and Producer Gas.” PhD thesis, 1–195; Banapurmath et al. 2011, Waste and Biomass Valorization 2: 1–11). In this context, the main objective of the present work is to study methods of biofuel production such as Honge oil methyl ester (HOME) using a conventional transesterification process and bioethanol from the Calliandra calothyrsus shrub using a new pretreatment method known as hydrothermal explosion. Further, experimental investigations were carried out on a single-cylinder, four-stroke, direct-injection stationary diesel engine operating in a dual-fuel mode using HOME, bioethanol and producer gas combinations to determine its performance, combustion and emission characteristics. The performance of the dual-fuel engine was analyzed at optimized engine conditions. HOME-Bioethanol (BE) blends such as HOME+ 5% bioethanol (BE5), HOME+ 10% bioethanol (BE10) and HOME+ 15% bioethanol (BE15) were prepared by adding bioethanol to HOME (on volume basis) in different proportions ranging from 5 to 15% with an increment of 5%. In this present work, the effect of different BE blends on the performance of producer gas fuelled dual fuel engine was studied. Experimental investigation on dual fuel engine using BE5-Producer gas operation resulted in up to 4–9% increased brake thermal efficiency with decreased hydrocarbon (HC), carbon monoxide (CO) and marginally increased nitric oxide (NOx) emission levels compared to HOME-Producer gas, BE10-producer gas and BE15-producer gas mode of operation. However, it was observed that, the overall performance of BE-producer gas operation was found to be lower compared to diesel-producer gas operation.

Throttleless and EGR-controlled stoichiometric combustion in a diesel–gasoline dual-fuel compression ignition engine

Stoichiometric Diesel and Gasoline Dual-fuel (Dieseline) Compression Ignition (SDCI) combustion using three-way catalyst (TWC) after-treatment is a promising technology to address the challenge issues of fuel consumption and emissions in future internal combustion engines. The authors use EGR instead of the throttle to control the load of the dual fuel compression ignition combustion engine. In order to investigate the fuel consumption and emission characteristics of SDCI combustion, a series of experiments were conducted in a modified single cylinder diesel engine using gasoline with a small portion of diesel for ignition enhancement. The experimental results show that SDCI combustion can achieve high indicated thermal efficiencies in a relatively wide range of loads (IMEP 4.3–8.0bar) because of a higher compression ratio, shorter combustion and smaller pumping losses. An attractive indicative specific fuel consumption (ISFC) of 190.8g/kWh has been achieved at a medium load without any boosting and the PM emissions are lower than for conventional diesel combustion. Different diesel percentages in the dual fuel supply have shown a significant impact on the ignition process and provide a wider available time range for combustion phase control. Diesel direct injection (DI) timing has a greater effect on PM emissions than the fuel ratio. Late DI timing reduces the thermal efficiency and results in higher PM emissions. Early DI timing and less diesel are preferable in order to reduce or avoid the diffusion combustion stage, which may lead to high PM emissions in the stoichiometric combustion.

An Enabling Study of Low Temperature Combustion With Ethanol in a Diesel Engine

Previous research indicates that the low temperature combustion (LTC) is capable of producing ultra-low nitrogen oxides (NOx) and soot emissions. The LTC in diesel engines can be enabled by the use of heavy exhaust gas recirculation (EGR) at moderate engine loads. However, when operating at higher engine loads, elevated demands of both intake boost and EGR levels to ensure ultra-low emissions make engine controllability a challenging task. In this work, a multifuel combustion strategy is implemented to improve the emission performance and engine controllability at higher engine loads. The port fueling of ethanol is ignited by the direct injection of diesel fuel. The ethanol impacts on the engine emissions, ignition delay, heat-release shaping, and cylinder-charge cooling have been empirically analyzed with the sweeps of different ethanol-to-diesel ratios. Zero-dimensional phenomenological engine cycle simulations have been conducted to supplement the empirical work. The multifuel combustion of ethanol and diesel produces lower emissions of NOx and soot while maintaining the engine efficiency. The experimental setup and study cases are described, and the potential for the application of an ethanol-to-diesel multifuel system at higher loads has been proposed and discussed.

Experimental investigation of the effects of diesel injection strategy on gasoline/diesel dual-fuel combustion

This study investigates the effects of diesel injection strategies on combustion, emissions, fuel economy and the operation range with high efficiency and low emissions fuelled with gasoline/diesel dual fuel on a modified single-cylinder diesel engine. This gasoline/diesel dual-fuel combustion mode proposes port fuel injection of gasoline and direct injection of diesel fuel with rapid in-cylinder fuel blending. Single and double injection strategies were employed in the engine experiments at 1500rev/min and 50mg/cycle total equivalent diesel fuelling rate. The experimental results showed that this combustion mode had the capability of achieving high efficiency with near zero NOx and soot emissions by using an early injection timing of single (E-single) strategy with high gasoline ratio (Rg). Parameters were optimized in double injection strategy included the first and second injection timing, injected diesel mass split between the two injections and the premixed gasoline ratio. Based on the optimized results, the comparison between single and double injection strategies was investigated. Compared to other three injection strategies, the early second injection timing (E-SOI2) strategy achieved the lowest indicated specific fuel consumption (ISFC) of 173g/kWh, the NOx and soot emissions were below 0.2, 0.003g/kWh respectively, but the maximum pressure rise rate (MPRR) was penalized, while the late second injection timing (L-SOI2) strategy was most favorable at reducing MPRR because of prolonged combustion duration. E-single and E-SOI2 strategies were difficult at high loads due to the high MPRR. Therefore, L-SOI2 strategy is an effective approach to expand the operation range to higher load. However, the upper load was limited by high soot emissions, which demanded increasing the diesel injection pressure. Under the operating conditions with optimized parameters, the maximum indicated mean effective pressure (IMEP) can be expanded up to 1.391MPa by using L-SOI2 strategy with increased fuel mass while still maintaining good emissions and MPRR within a given criteria.

Dimethyl ether energy ratio effects in a dimethyl ether-diesel dual fuel premixed charge compression ignition engine

The combination of port DME induction and in-cylinder diesel direct-injection compression ignition combustion was studied in a two-cylinder engine. The port DME energy ratio was proved to be one of main variables affecting the combustion. Thus, the main goals of this paper were to investigate the effects of DME energy ratio on combustion and emission characteristics of the diesel engine at this dual-fuel PCCI combustion mode. In order to evaluate the characteristics of this combustion mode, the conventional direct-injection compression ignition engine performance was provided to make a detailed comparison. Furthermore, special concern was focused on the complex combustion process analysis. DME port induction and diesel in-cylinder direct-injection combustion process was composed of the homogeneous charge compression ignition combustion and conventional diffusive combustion. Although DME energy ratio had little impact on the start timing of cool flame, the negative temperature coefficient region shortened and the start timing of HCCI high-temperature reaction advanced as DME energy ratio increased. It could also be discovered that, as DME energy ratio increased, the maximum heat release rate of DME HCCI increased as well as the peak values of cylinder pressure and mass-averaged temperature; however, the maximum heat release rate of diesel combustion decreased. Results also showed the brake thermal efficiency slightly increased with a rise of DME energy ratio. In the case of emission, smoke emissions decreased, NOx emissions decreased first but this decreasing trend was inhibited later, while HC and CO emissions increased with a rise of DME energy ratio.

Exergy analysis of a diesel engine operated with koroch seed oil methyl ester and its diesel fuel blends

This study focuses on exergy analysis of a single cylinder four stroke direct injection (DI) diesel engine using 10% (B10), 20% (B20), 30% (B30) and 40% (B40) blending of Koroch seed oil methyl ester (KSOME) with conventional diesel fuel. The analysis corresponds to steady state engine operations under variable load conditions. For each fuel operation at various loads, exergetic performance parameters are evaluated. It was found that the exergy destruction was more with the KSOME fuel blends compared to diesel fuel operation at all the engine loads. Exergy destruction also increases with increasing biodiesel content in the blend and it was significantly higher for fuel operation with B40 at various loads. Results also show that the engine exergetic efficiency is less in case of fuel operation with the biodiesel blends. The analysis indicates the scope of further improvement in engine operation with biodiesel fuel blends particularly with B40 and the higher percentage blends.

The Effect of Ethanol Addition in a Biodiesel Operated DI Diesel Engine on Combustion, Performance, and Emission Characteristics

In this study, diesel fuel, biodiesel, and biodiesel–ethanol blends (BEBs) were tested in a single cylinder direct-injection (DI) diesel engine to investigate the combustion, performance, and emission characteristics of the engine at the maximum torque and an engine speed of 1500 rpm. The results indicate that when compared with biodiesel, the combustion characteristics of BE blends changed; the engine performance has improved slightly with 5% ethanol in biodiesel (BEB5). The brake thermal efficiency increases slightly with lower blends and no significant improvement with higher ethanol blends. The effectiveness of NOx and smoke density increases with increasing ethanol in the blends. With a high percentage of ethanol in the BE blends, the hydrocarbon (HC) and carbon monoxide (CO) emissions could increase. But the use of BEB5 could reduce the HC and CO emissions as well. In general, the BE blends have lower NOx emissions, compared with biodiesel and diesel fuel. The smoke density decreases for lower ethanol blends compared with diesel and biodiesel fuel. On the whole, the BE blends give lower HC, CO, smoke density, and NOx emission compared with diesel fuel. But the additions of more ethanol with biodiesel have no significant improvement in the emission levels.

Comparative study on Gasoline Homogeneous Charge Induced Ignition (HCII) by diesel and Gasoline/Diesel Blend Fuels (GDBF) combustion

Gasoline Homogeneous Charge Induced Ignition (HCII) by diesel uses port fuel injection of gasoline to form a homogeneous charge and direct injection of diesel fuel as an ignition source. Gasoline/Diesel Blend Fuels (GDBFs) uses a premixed blend of diesel and gasoline which is directly injected into the cylinder for combustion. Exploratory studies show that these two ways may integrate the advantages of gasoline and diesel fuels to achieve high thermal efficiency and low emission targets. Combustion characteristics, emission characteristics, thermal efficiency and adaptability of low-temperature combustion in these two combustion modes have been comparatively investigated on a high-pressure common rail single-cylinder diesel engine. The results show that both HCII and GDBF modes can achieve higher thermal efficiency than gasoline SI combustion and a similar or even higher thermal efficiency than diesel CI combustion because the combustion was closer to constant volume combustion. As gasoline ratio increases, the fuel–air mixing is improved in both HCII and GDBF modes, and thus soot emissions reduced dramatically, with a biggest reduction of 90%. The ignition delay in HCII mode remained almost the same, while the ignition delay in GDBF mode increased significantly with the increase of gasoline ratio. As gasoline ratio increases, the combustion duration in both HCII and GDBF modes shortened significantly. Both HCII and GDBF modes can achieve low temperature combustion with extremely low soot and NO emissions when combined with large amounts of EGR. These modes demonstrate an advantage over the diesel CI combustion mode, where the NO emissions decreased and soot emissions increased with the increase of EGR, exhibiting the classical NO-soot trade-off.

Numerical and experimental study of combustion and emission characteristics in gasoline direct-injection compression ignition engines using intake preheating

This paper presents a numerical and experimental study of the combustion and emission characteristics of a gasoline direct-injection compression ignition engine using intake preheating. The gasoline direct-injection compression ignition engine was predicted to reduce emissions compared with the emissions from a conventional diesel engine. To compare the combustion and emission characteristics of the gasoline direct-injection compression ignition and diesel engines, numerical modelling was conducted using the KIVA-3V release 2 code, which is integrated with the Chemkin chemistry solver II. Numerical simulations were performed under a variety of conditions to determine the optimal conditions for gasoline direct-injection compression ignition engine operation. In order to achieve the gas pressure in the cylinder and the emission characteristics, experiments were performed using a single-cylinder engine. The simulation results agreed well with the experimental data. The gasoline autoignition was in the parcels with a lower equivalence ratio of 0.6–0.8 as opposed to the diesel autoignition parcels with a high equivalence ratio of greater than 1. The ignition delay of gasoline was longer than that of diesel; therefore, the gasoline direct-injection compression ignition engine could reduce the soot emissions. The nitrogen oxide emission levels for gasoline direct-injection compression ignition were increased because of the intake preheating.

Empirical Study of Simultaneously Low NOx and Soot Combustion With Diesel and Ethanol Fuels in Diesel Engine

Diesel low temperature combustion (LTC) is capable of producing diesel-like efficiency while emitting ultra-low nitrogen oxides (NOx) and soot emissions. Previous work indicates that well-controlled single-shot injection with exhaust gas recirculation (EGR) is an operative way of achieving diesel LTC from low to mid engine loads. However, as the engine load is increased, demanding intake boost and injection pressure are necessary to suppress high soot emissions during the transition to LTC. The use of volatile fuels such as ethanol is deemed capable of promoting the cylinder charge homogeneity, which helps to overcome the high soot challenge and, thus, potentially expand the engine LTC load range. In this work, LTC investigations were carried out on a high compression ratio (18.2:1) engine. Engine tests were first conducted with diesel and LTC operation at 8 bar indicated mean effective pressure (IMEP) was enabled by sophisticated control of the injection pressure, injection timing, intake boost, and EGR application. The engine performance was characterized as the baseline, and the challenges were identified. Further tests were aimed to improve the engine performance against these baseline results. Experiments were, hence, conducted on the same engine with secondary ethanol port fuelling (PF). Single-shot diesel direct injection (DI) was applied close to top dead center (TDC) to ignite the ethanol and control the combustion phasing. The control sensitivity was studied through injection timing sweeps and EGR sweeps. Additional tests were performed to investigate the ethanol-to-diesel ratio effects on the mixture reactivity and the engine emissions. Engine load was also raised to 16.4 bar IMEP while keeping the simultaneously low NOx and soot emissions. Significant improvement of engine control and emissions was achieved by the DI+PF strategy.

Particle Number Emissions of Nonroad Diesel Engines of Various Ages

Over the last two decades, gaseous and particle mass emissions of new diesel engines have been reduced effectively and progressively in response to the emissions legislation and due to the applied new technologies. There is, however, increasing concern about whether the engine modifications, while improving combustion and reducing emissions, have increased the number emissions of ultrafine and nanoparticles. So far, emissions regulations have solely been based on particulate matter (PM) mass measurements, not on particle number. Nanoparticles, however, form a major part of the PM emissions, but they do not considerably contribute to the PM mass and cannot be seen as a problem, if only PM mass is determined. Therefore, there is increasing interest in expanding the scope of the regulations to also include particle number emissions, e.g., Euro VI for on-road engines. The PM number limit will also be enforced for nonroad engines slightly later. Thus, more information is required about the particle number emissions themselves, but also about the effects of the engine technology on them. Wall-flow diesel particulate filters reduce the particle number very effectively within the entire particle size range. Nevertheless, in order to keep the filter as small as possible and to lessen the need for regeneration, the engine-out PM number should also be minimized. If the diesel particulate filters (DPFs) could be left out or replaced by a simpler filter, there would be greater freedom of space utilization or cost savings in many nonroad applications. This might be realized in installations where the engine is tuned at high raw NOx and a selective catalytic reduction (SCR) system is adopted for NOx reduction. However, it is not self-evident that new engine technologies would reduce the PM number emissions sufficiently. In this study, particle number emissions were analyzed in several nonroad diesel engines, representing different engine generations and exploiting different emissions reduction technologies: four- or two-valve heads, exhaust gas recirculation, different injection pressures and strategies, etc. All engines were turbocharged, intercooled, direct-injection nonroad diesel engines. Most engines used common-rail fuel injection technology. Comparisons were, however, also performed with engines utilizing either a distributor-type or an in-line fuel injection pump to see the long-term development of the particle number emissions. In this paper, the PM number emissions of nine nonroad diesel engines are presented and compared. Gaseous exhaust emissions and fuel consumption figures are also provided.

Stochastic reactor modelling of multi modes combustion with diesel direct injection or hydrogen jet ignition start of combustion

Recent papers [1–5] have proposed two different systems to more efficiently and more rapidly burn the fuel in highly boosted, high compression ratio, directly injected internal combustion engines permitting multi-mode combustion operation. In a first system, a second direct injector is coupled with the standard Diesel direct injector and glow plug. The second direct injector introduces the most of the fuel while the Diesel direct injector only introduces a minimum amount of fuel to control the start of the combustion about top dead centre. The fuel injected before the Diesel ignition injection burns premixed, the fuel injected after the Diesel ignition injection burns diffusion. This design permits combustion premixed gasoline-like if all the fuel is injected before the Diesel ignition injection, diffusion Diesel-like if all the fuel is injected after the Diesel ignition injection (as done in the Westport High Pressure Direct Injection concept [12]), and mixed gasoline/Diesel like injecting the fuel before and after the Diesel ignition injection. The premixed gasoline-like mode is actually a homogeneous charge compression ignition (HCCI)-like mode, where an amount of fuel smaller than the threshold value producing top dead centre auto ignition is then ignited at top dead centre by the Diesel ignition injection in a more robust, stable and repeatable operation unaffected by small changes in properties and composition of the fuel and air mixture. In an alternative design, the glow plug is replaced by a jet ignition devices feed preferably with H2. In this case, a spark ignition ignites the stoichiometric H2-air mixture within the jet ignition pre-chamber. The jets of hot reacting H2-air combusting gases then ignite the main chamber premixed mixture in the gasoline-like operation or create suitable conditions for the fuel subsequently injected to burn diffusion in the Diesel-like operation or perform both duties in the mixed gasoline/Diesel-like operation. A single main chamber direct injector is generally needed (for example with H2, CH4 or C3H8 fuels). With NH3, a second main chamber direct injector with H2 is also used to limit the volume of the jet ignition pre-chamber. In this short communications, the results of detailed chemistry simulations with the SRM (Stochastic Reactor Model) suite, a sophisticated engineering tool combining conventional 1D or 3D fluid dynamics approaches are presented to further support these two engine concepts working with fuels H2, CH4, C3H8, NH3, I-C8H18 and N-C7H16 and adopting two different mechanisms for chemical kinetics. Within the limits of the present simulations (a very accurate chemical kinetic for combustion of I-C8H18 and N-C7H16 but a much less accurate chemical kinetic for the other fuels and especially for NH3, unavailability of variable composition and variable properties multiple injections), the Diesel injection ignition and the hydrogen jet ignition are proved to permit combustion modes leading to indicated thermal efficiencies up to 10% better than the latest Diesels at high loads within the same peak pressure and peak temperature constraints.

Reactivity Controlled Compression Ignition Using Premixed Hydrated Ethanol and Direct Injection Diesel

The present study uses numerical simulations to explore the use of hydrated (wet) ethanol for reactivity controlled compression ignition (RCCI) operation in a heavy duty diesel engine. RCCI uses in-cylinder blending of a low reactivity fuel with a high reactivity fuel and has demonstrated significant fuel efficiency and emissions benefits using a variety of fuels, including gasoline and diesel. Combustion timing is controlled by the local blended fuel reactivity (i.e., octane number), and the combustion duration can be controlled by establishing optimized gradients in fuel reactivity in the combustion chamber. In the present study, the low reactivity fuel was hydrated ethanol while the higher reactivity fuel was diesel. First, the effect of water on ethanol/water/diesel mixtures in completely premixed HCCI combustion was investigated using GT-Power and single-zone CHEMKIN simulations. The results showed that the main impact of the water in the ethanol is to reduce the initial in-cylinder temperature due to vaporization cooling. Next, multi-dimensional engine modeling was performed using the KIVA code at engine loads from 5 to 17 bars IMEP at 1300 rev/min with various grades of hydrated ethanol and a fixed diesel fraction of the total fuel. The results show that hydrated ethanol can be used in RCCI combustion with gross indicated thermal efficiencies up to 55% and very low emissions. A 70/30 ethanol/water mixture (by mass) was found to yield the best results across the entire load range without the need for EGR.

Influence of static injection timing on combustion, emission and performance characteristics of DI diesel engine fuelled with honne oil methyl ester

This study is aimed to investigate experimentally the combustion, exhaust emissions and performance characteristics of a direct injection (DI) diesel engine, typically used in the agricultural sector, when fuelled with neat diesel (ND), and abundantly available but untapped honne oil methyl ester (HOME) is used in diesel engines. The static injection timing (SIT) is varied from 23 crank angle (CA) (manufacturer's specified value) to 28 CA. The combustion parameters of HOME improved as SIT increased. The brake thermal efficiency (BTE) of HOME (SIT 27–28 CA before top dead centre (bTDC)) is the highest; however, still it is less than ND. The emissions (smoke opacity (SO), CO, HC and NO x ) of HOME (SIT 23–28 CA bTDC), through out the entire load range, are dropped compared to ND. The reductions in exhaust emissions (SIT 27–28 CA bTDC) together with increase in BTE made the HOME (SIT 27–28 CA bTDC) a suitable alternative fuel for diesel fuel and thus could help in controlling air pollution.

Performances and Emissions of a DI Supercharged Diesel Engine Fuelled with Soybean Biodiesel and its Blends

Biodiesel is one kind of renewable fuel produced from biomass oil. To optimize the application of biodiesel on vehicle diesel engines, we conducted the tests on a four cylinder turbocharged direct injection (DI) diesel engine fuelled with biodiesel-diesel blends of different ratios, measured their power outputs, fuel consumption and emissions, and compared with those of diesel fuel. Experimental results show that fuelled with biodiesel, at external characteristics (speed characteristics of full load), the power performance is almost the same, brake specific energy consumption (BSEC) decreases, smoke and HC emissions decrease, and NOx and CO emissions increase; at load characteristics, BSEC decreases, smoke emission decreases at high loads and keeps almost no change at low and middle loads, NOx emission increases, HC emission decreases at low and middle loads and keeps the same at high loads, and CO emission maintains the same. B20 (biodiesel content of 20%) is an optimum solution for vehicle engines under comprehensive analysis of performances and emissions.

Piston Bowl Optimization for RCCI Combustion in a Light-Duty Multi-Cylinder Engine

Reactivity Controlled Compression Ignition (RCCI) is an engine combustion strategy that that produces low NO{sub x} and PM emissions with high thermal efficiency. Previous RCCI research has been investigated in single-cylinder heavy-duty engines. The current study investigates RCCI operation in a light-duty multi-cylinder engine at 3 operating points. These operating points were chosen to cover a range of conditions seen in the US EPA light-duty FTP test. The operating points were chosen by the Ad Hoc working group to simulate operation in the FTP test. The fueling strategy for the engine experiments consisted of in-cylinder fuel blending using port fuel-injection (PFI) of gasoline and early-cycle, direct-injection (DI) of diesel fuel. At these 3 points, the stock engine configuration is compared to operation with both the original equipment manufacturer (OEM) and custom machined pistons designed for RCCI operation. The pistons were designed with assistance from the KIVA 3V computational fluid dynamics (CFD) code. By using a genetic algorithm optimization, in conjunction with KIVA, the piston bowl profile was optimized for dedicated RCCI operation to reduce unburned fuel emissions and piston bowl surface area. By reducing these parameters, the thermal efficiency of the engine was improved while maintaining low NOx and PMmore » emissions. Results show that with the new piston bowl profile and an optimized injection schedule, RCCI brake thermal efficiency was increased from 37%, with the stock EURO IV configuration, to 40% at the 2,600 rev/min, 6.9 bar BMEP condition, and NOx and PM emissions targets were met without the need for exhaust after-treatment.« less

Numerical Simulation on Effect of Nozzle-Hole Layout on Spray Characteristics and Combustion in a DI Diesel Engine

Diesel spray characteristics are closely related to the combustion of the engine where the spray tip penetration and the fuel atomization play a key role especially for direct injection (DI) diesel engine. With different nozzles, the fuel atomization and evaporation will be different thereby affecting the combustion and emission characteristics. A three-dimensional model is built based on the parameters of a DI diesel engine, and its validation is also validated. Three nozzle-hole layouts are designed in this research, including the conventional hole, multi-hole, and group-hole. The spray characteristics and combustion process are studied with three different nozzle-hole layouts by the way of numerical simulation. Further more, the effect of inter-hole spacing of group-hole nozzle on the evaporation rate and combustion process is researched here.

Effect of injection timings on the performance, emission and combustion characteristics of DI diesel engine running on Calophyllum inophyllum linn oil (honne oil)

The present work examines the use of a non-edible vegetable oil namely honne oil, a new possible alternative fuel for diesel engine. A direct injection (DI) diesel engine typically used in agricultural sector was operated on neat diesel (ND) and neat honne oil (H100). Static injection timing (start of static injection timing) was changed to study the performance, emission and combustion characteristics. It was observed that advancing the injection timing with H100 from the rated static injection timing (23° bTDC) increased the brake thermal efficiency and reduced CO, HC emissions and smoke opacity; however, NOx emission was increased. The ignition delay with H100 was higher than that with ND for all static injection timing under consideration. Improved premixed heat release rate was observed with H100 when the static injection timing is advanced however, for 28° bTDC premixed heat release rates decreased. The best static injection timing was found to be 27° bTDC for H100 based on brake thermal efficiency.

Simulation Research on Post-Injection of Electronically Controlled Heavy-Duty Diesel Engine

GT-Suite software is used to establish the simulation model of electronic fuel injection system for 16V280ZJ diesel engine. Combustion process simulation calculation is conducted to the direct injection (DI) diesel engine based on a main-post double injection scheme. Simulation parameters are modified based on the comparison with given experimental results. The calculation results effectively reflect the influence of fuel ratio and the interval angle between main and post injection over emission and fuel economy. Finally, in order to improve the engine emissions and reduce the pressure rise rate, we get the optimal injection solution for the main-post injection mode.

Performance and emission characteristics of a diesel engine using esters of palm olein/soybean oil blends

In this experimental study, the engine performance and exhaust emissions of a diesel direct injection engine using mixed palm olein?soybean vegetable oil ethyl ester (POSEE) and methyl ester (POSME) have been examined. The results of experimental studies have shown that the torque and brake power output of an engine, which uses biodiesels, is slightly lower and specific fuel consumption is higher than in an engine using conventional diesel fuel. It has also been observed that there is a decrease in both carbon monoxide and hydrocarbon (HC) emissions, which indicates an advantage of exhaust emissions. Although methyl ester's CO2 emissions decreased compared with those of diesel fuel, NO and NOX emissions were higher with the biodiesels.