Fuel Injection Spark Ignition Engine Research Articles

Experimentally Investigating the Potential of Iso-Stoichiometric GEM Blends as a Drop-in Replacement for E50 in SI Engines

Background: Research on alternative fuels for internal combustion engines is crucial due to climate change and energy security concerns. Ethanol-blended gasoline has been a popular alternative fuel, but biomass limitations restrict its widespread use. Methanol offers a solution as it can be produced from non-food sources, extending ethanol's availability. Objective: This study explores a ternary fuel blend consisting of gasoline, ethanol, and methanol as an alternative to binary gasoline-ethanol blend. The objective is to investigate if the isostoichiometric ternary blend offers equivalent fuel properties to E50 (Ethanol 50%, Gasoline 50% (v/v)) gasohol while potentially enhancing engine performance, reducing emissions, and improving combustion characteristics. Methods: A single-cylinder, four-stroke, port fuel injection spark ignition engine was used. The engine was tested with three fuels: pure gasoline, E50 blend, and an equivalent iso-stoichiometric GEM blends. Engine tests were conducted at constant load with varying engine speeds. Performance, emission, and combustion parameters were experimentally measured and compared across all fuels. Results: E50 and its equivalent blends improved brake thermal efficiency but increased brake specific fuel consumption compared to gasoline. It significantly reduced unburned hydrocarbon and carbon monoxide emissions but slightly increased nitrogen oxide emissions. Conclusion: Formulated E50 equivalent blends have identical air to fuel ratio, lower heating values as conventional binary E50 gasoline-ethanol blends. The study suggests that iso-stoichiometric GEM blends have the potential to be a viable alternative drop-in fuel for E50 in internal combustion engines. The future advancements in GEM blends, particularly in optimizing ratios, could lead to patentable inventions.

Environmental, combustion, and performance investigation of low viscous biofuel in port fuel injection spark-ignition engine

Environmental, combustion, and performance investigation of low viscous biofuel in port fuel injection spark-ignition engine

Study on hydrogen substitution in a compressed natural gas spark-ignition passenger car engine

Hydrogen substitution in applications fueled by compressed natural gas arises as a potential alternative to fossil fuels, and it may be the key to an effective hydrogen economy transition. The reduction of greenhouse gas emissions, especially carbon dioxide and unburned methane, as hydrogen is used in transport and industry applications, makes its use an attractive option for a sustainable future. The purpose of this research is to examine the gradual adoption of hydrogen as a fuel for light-duty transportation. Particularly, the study focuses on evaluating the performance and emissions of a single-cylinder port fuel injection spark-ignition engine as hydrogen is progressively increased in the natural gas-based fuel blend. Results identify the optimal conditions for air dilution and engine operation parameters to achieve the best performance. They corroborate that the dilution rate has to be adjusted to control pollutant emissions as the percentage of hydrogen is increased. Moreover, the study identifies the threshold for hydrogen substitution below which the reduction of carbon dioxide emissions due to efficiency gains is negligible compared to the reduction of the carbon content in the fuel blend. These findings will help reduce the environmental footprint of light-duty transportation not only in the long term but also in the short and medium terms.

Effect of Hydrogen-Rich Syngas Direct Injection on Combustion and Emissions in a Combined Fuel Injection—Spark-Ignition Engine

To utilize the high efficiency of gasoline direct injection (GDI) and solve the high particulate number (PN) issue, hydrogen-rich syngas has been adopted as a favorable sustainable fuel. This paper compares and analyzes the effects of the injection configurations (GDI, gasoline port injection combined with GDI (PGDI), and gasoline port injection combined with hydrogen-rich syngas direct injection (PSDI)) and fuel properties on combustion and emissions in a spark-ignition engine. The operational points were fixed at 1800 rpm with a 15% throttle position, and the excess air ratio was 1.1. The conclusions show that PSDI gained the highest maximum brake thermal efficiency (BTE) at the MBT point, and the maximum BTE for GDI was only 94% of that for PSDI. PSDI’s CoVIMEP decreased by 22% compared with GDI’s CoVIMEP. CO and HC emissions were reduced by approximately 78% and 60% from GDI to PSDI among all the spark timings, respectively, while PSDI emitted the highest NOX emissions. As for particulate emissions, PSDI emitted the highest nucleation-mode PN, while GDI emitted the lowest. However, the accumulation-mode PN emitted from PSDI was approximately 52% of that from PGDI and 5% of that from GDI. This study demonstrates the benefits of PSDI for sustainability in vehicle engineering.

Modeling of a port fuel injection spark-ignition engine with different compression ratios using methanol blends with the response surface methodology

In this study, the response surface methodology was applied to verify the optimum compression ratio, methanol percentage, and engine load in order to obtain the best levels of engine response that will occur when using methanol (0, 10, and 20% by vol.) in a spark-ignition engine under different compression ratio (6.0:1, 8.0:1, and 10.0:1) and engine load (8, 10, and 12 kg) conditions. A response surface methodology aided by analysis of variance was created using the three-factor and three-level central composite full design with the results of the experiment. With the created model, optimum methanol percentage, compression ratio, and engine load levels corresponding to the finest brake thermal efficiency, brake-specific fuel consumption, carbon monoxide, carbon dioxide, hydrocarbon, and nitrogen oxide emission levels were determined. According to the optimization results, the optimum methanol percentage, compression ratio, and engine load were found to be 10.5%, 6.0:1, and 12 kg, respectively. Hydrocarbon, nitrogen oxide, carbon monoxide, carbon dioxide, brake thermal efficiency , and brake-specific fuel consumption corresponding to optimum operating conditions were determined as 63.568 ppm, 840.643 ppm, 0.365%, 14.059%, 28.199%, and 0.286 kg/kWh, respectively. To test the reliability of the response surface methodology results, experiments with optimal methanol, compression ratio, and engine load were carried out and compared with the response surface methodology findings. As a result, it can be said that the response surface methodology is a successful application for the optimization of a spark-ignition engine using methanol as an alternative fuel with different engine parameters.

Potential of compression ratio and exhaust gas dilution on improving combustion and nitrogen oxides emission performance on a PFI engine fueled with methanol

Methanol is a promising alternative fuel, and the effects of compression ratio (CR) and exhaust gas recirculation (EGR) of a port fuel injection spark ignition engine modified from a diesel engine fueled with methanol were studied in this paper. The results showed that with the increase of the EGR rate, flame propagation slowed down, heat release rate and the pressure rise rate decreased, and the combustion lag phenomenon was more obvious in the high EGR range. Under light load and high engine speed conditions, the combustion parameters were more sensitive to the variation of EGR rate. Increasing the CR was beneficial to improve combustion stability. Higher CR and introducing exhaust gas into cylinder both can improve break thermal efficiency and fuel economy performance. EGR strategy showed great capacity on reducing NOx emissions. By Taguchi and ANOVA analysis, it was found that higher EGR rate and small CR were benefit for NOx emission, but higher CR was suitable for decreasing BSFC, 17:1 was an optimal CR for this engine. The influence ratio of EGR on NOx emissions reached 88%, and the engine operating condition had the greatest influence on BSFC, followed by EGR rate.

Experimental performance investigation of an electronic fuel injection-SI engine fuelled with HCNG (H2 + CNG) for cleaner transportation

Hydrogen blended CNG (HCNG) is an attractive alternative to existing fossil fuels. In this study, efficacy of the HCNGs blended with various hydrogen proportions (HCNG15, HCNG20, and HCNG30) are determined. To analyze the performance of these fuels, electronic fuel injection spark ignition engine (EFI-SI engine) is considered, as this engine is commercialized, and commonly used in Thailand. A performance study for the proposed HCNGs over a wide engine speed range (1500–6000 rpm) is carried out and is compared to Gasohol-91 (E10) and pure CNG, the conventional fuels used in the country. All tests are performed with the butterfly valve partially opened at 75%. Interestingly, the specific fuel consumptions of HCNGs are less than those of pure CNG, although torque and brake power are significantly diminished. It is found that increasing the proportion of hydrogen (HCNG30) lowered the engine torque and power. It is worth noting that enrichment of hydrogen increased the brake thermal efficiency maximum of 23.75%, 23.20%, 22.31% and 21.59% for HCNG30, HCNG20, HCNG15 and CNG, respectively. For the emission aspects, HCNG fuels greatly reduced the CO, CO2 and NOx as compared to that of conventional fuels. Therefore, using these green fuels can considerably support the greenhouse gases reduction campaign. Finally, HCNG20 is recommended as a compromise alternative fuel for EFI-SI engine which is environmentally friendly.

Individual Cylinder Combustion Optimization to Improve Performance and Fuel Consumption of a Small Turbocharged SI Engine

Stringent exhaust emission and fuel consumption regulations impose the need for new solutions for further development of internal combustion engines. With this in mind, a refined control of the combustion process in each cylinder can represent a useful and affordable way to limit cycle-to-cycle and cylinder-to-cylinder variation reducing CO2 emission. In this paper, a twin-cylinder turbocharged Port Fuel Injection–Spark Ignition engine is experimentally and numerically characterized under different operating conditions in order to investigate the influence of cycle-to-cycle variation and cylinder-to-cylinder variability on the combustion and performance. Significant differences in the combustion behavior between cylinders were found, mainly due to a non-uniform effective in-cylinder air/fuel (A/F) ratio. For each cylinder, the coefficients of variation (CoVs) of selected combustion parameters are used to quantify the cyclic dispersion. Experimental-derived CoV correlations representative of the engine behavior are developed, validated against the measurements in various speed/load points and then coupled to an advanced 1D model of the whole engine. The latter is employed to reproduce the experimental findings, taking into account the effects of cycle-to-cycle variation. Once validated, the whole model is applied to optimize single cylinder operation, mainly acting on the spark timing and fuel injection, with the aim to reduce the specific fuel consumption and cyclic dispersion.

Soot contamination of engine oil – the case of a small turbocharged spark-ignition engine

The paper presents the results of thermogravimetric tests of engine oil used in a small turbocharged spark-ignition engine. The main observation from the research was a significant soot contamination of engine oil, that appears even at its low mileage. This indicates that also in the case of port fuel injection spark-ignition engine, high particulate matter emissions may occur. It may therefore turn out that the small city car can be more harmful to the environment than much larger vehicles. A rapid soot contamination of the oil in this engine indicates as well that the oil change interval should be shortened.

Effects of knocking on the performance and emissions of a single cylinder SI engine fueled with a fuel blend of iso-octane and aromatic hydrocarbons

This study investigated the effects of knocking on the performance and emissions of a single cylinder port fuel injection spark-ignition engine. Three types of hydrocarbon compounds were used as fuels in this study: iso-octane, aromatic hydrocarbons, and a mixed fuel composed of iso-octane and aromatic hydrocarbons. The ignition timing was varied to investigate the effects of fuel composition and knocking from 10° to 40° before top dead center. The experimental results indicated that as the fuel evaporation improved, the ignition delay and combustion duration were shortened. Additionally, the knocking of fuels with these characteristics occurred earlier than the other fuels, and the knocking intensity of these fuels was stronger. A fuel with a greater iso-octane content improved the engine performance, including the brake mean effective pressure (BMEP) and brake thermal efficiency (BTE), better than a fuel containing a greater content of aromatic hydrocarbons. The intensity of the knocking increased as the ignition timing was advanced, thereby causing a decrease in the BMEP and BTE. Additionally, the knocking intensities of fuels with high iso-octane contents were weaker than the other examined fuels. There were no significant changes in gaseous emissions, including the total hydrocarbon and NOx emissions when knocking occurred. However, particulate emissions sharply increased as the knocking intensity increased.

Journal Vol – 15 No -7, July 2020 Journal > Journal > Journal Vol – 15 No -7, July 2020 > Page 6 PERFORMANCE AND EMISSION CHARACTERISTICS OF GASOLINE-ETHANOL BLENDS ON PFI-SI ENGINE Authors: D.Vinay Kumar ,G.Samhita Priyadarsini,V.Jagadeesh Babu,Y.Sai Varun Teja, DOI NO: https://doi.org/10.26782/jmcms.2020.07.00051 admin July 26, 2020 Abstract: Alcohol based fuels can be produced from renewable energy sources and

Journal Vol – 15 No -7, July 2020 Journal > Journal > Journal Vol – 15 No -7, July 2020 > Page 6 PERFORMANCE AND EMISSION CHARACTERISTICS OF GASOLINE-ETHANOL BLENDS ON PFI-SI ENGINE Authors: D.Vinay Kumar ,G.Samhita Priyadarsini,V.Jagadeesh Babu,Y.Sai Varun Teja, DOI NO: https://doi.org/10.26782/jmcms.2020.07.00051 admin July 26, 2020 Abstract: Alcohol based fuels can be produced from renewable energy sources and

A Comparison Study on Emission Characteristics of Using Higher Alcohol Oxygenates with Gasoline in a Multipoint Fuel Injection Spark-Ignition Engine

Abstract Usage of oxygenates has become common practice for improving gasoline properties. In this study, two oxygenates, one from the ether family (diisopropyl ether (DIPE)) and one from the alcohol family (n-butanol), were mixed with gasoline at 5, 15, and 25 % by volume to get D5, D15, D25, N5, N15, and N25 blends. Blends of DIPE (D5, D15, and D25) and n-butanol (N5, N15, and N25) were tested in a four-stroke four-cylinder multipoint fuel injection spark-ignition engine at 0.33 MPa (brake mean effective pressure) over a speed range of 1,400 to 2,800 r/min with 200 r/min increments. The performance and emission behavior obtained from blends of DIPE and n-butanol were compared with base gasoline. Lower hydrocarbon and carbon monoxide emissions are observed for oxygenate blends than for gasoline. However, blends of DIPE and butanol emitted higher nitrogen oxide (NOx) than gasoline. The retarded spark timing from 14° before top-dead-center (bTDC) to 12° bTDC reduced NOx emissions from blends. The study also concludes that DIPE is a suitable and comparable oxygenate additive to n-butanol and offers high knock resistance equal to n-butanol.

Emission Experiment of Intake air Humidification of a Port Fuel Injected Spark Ignition engine

In this study, experimental analysis was carried out to investigate the effect of humidified air induction on emissions of a single cylinder, four stroke, air cooled, Royal Enfield Bullet engine 350cc, with modifications made to assist port fuel injection. Tests have been performed on test engine fuelled with gasoline over a range of engine loads and at rated speed for 75 % and 95 % relative humidity with water injection. The outcomes of the experimental analysis reveal that increasing the intake air humidity from 75 % to 95 % decreased the exhaust emissions of NOx, CO, HC and CO2 at 95% rated load of the engine without much or less impact on the thermal brake efficiency.

Performance and emission characteristics of a port fuel injected, spark ignition engine fueled by compressed natural gas

This paper presents an experimental study of the performance and emission characteristics of a port fuel injection spark ignition engine modified to fuel by compressed natural gas (CNG). Consequently, the original fuel supply system of the test engine was modified to flexibly run on either gasoline or CNG. The experiment was conducted to compare operating parameters of the test engine fueled by gasoline and CNG with the same air excess ratio (λ). The study results showed that when fueled by CNG, the brake power of the test engine decreases up to 19% and the brake specific energy consumption (BSEC) increases 14%. However, the exhaust emissions of the test engine fueled by CNG are enhanced dramatically. Indeed, CO2 emissions decrease up to 50%, NOx emissions decrease 20%, especially, CO and HC emissions reduce up to 90% and 96%, respectively. For the application of CNG in real-world conditions for in used vehicles, it is recommended that we have to concentrate to solve the problem related to the low power and high fuel consumption of the original engines fueled by CNG.

Characterization of flame front propagation during early and late combustion for methane-hydrogen fueling of an optically accessible SI engine

In recent years, hybrid and fully electric vehicles have received significant consideration since they represent an alternative sustainable transport to the conventional fossil-fuel powered vehicles. However, a worldwide implementation of this alternative propulsion can induce large and undesirable peak demands in distributed power systems. In this context, natural gas spark ignition engines are a promising form of technology to supply part of the energy demand. The main limitations related to low laminar flame propagation speed and poor lean-burn capabilities of natural gas can be overcome by using hydrogen as additional fuel. In this paper, a comparison was carried out between methane and different CH4/H2 mixtures. Specifically, low levels of hydrogen addition were used (5%, 10%, 20% volumetric basis) in stoichiometric and lean burn conditions. The measurements were carried out in an optically accessible single-cylinder port fuel injection spark ignition engine. Optical measurements were performed to analyze the combustion process with high spatial and temporal resolution. In particular, optical techniques based on 2D-digital imaging with two different combustion chamber views were used. Macroscopic (global) and microscopic (local) post-processing tools were implemented to provide a detailed analysis of the flame front propagation process. Moreover, an in-depth analysis was performed to study the flame penetration in the piston top-land crevice. Exhaust gas emissions were also characterized and linked with thermodynamic and optical data. In order to evaluate the combustion process in similar fluid-dynamic conditions, all measurements were performed under steady-state conditions at fixed engine speed, load and spark advance. All the results highlight fast combustion promotion due to the hydrogen addition. In addition, hydrogen reduces the preferential propagation of the flame in a certain direction and increases the flame front wrinkling. Flame propagation in the top-land crevice region was measured for methane and its blends with hydrogen, which represents an original contribution to the literature. An inverse trend was seen between flame penetration in the crevice and unburned hydrocarbon emissions. Lastly, tests in lean conditions demonstrate the potential to decrease nitrogen oxides emissions when methane and methane-hydrogen blends are used.

Effect of intake swirl on combustion performance in an unthrottled spark ignition engine

A Fully Hydraulic Variable Valve System is described in this article which can achieve continuous variation in valve lift, duration, and timing. The system was installed in a four-cylinder port fuel injection spark ignition engine and achieved unthrottled load control through early intake valve closing. The in-cylinder pressure measured experimentally showed that pumping losses of the unthrottled spark ignition engine at 2000 r/min and 0.189 MPa brake mean effective pressure was reduced by 85.4% compared with the throttled spark ignition engine. However, its slow and unstable combustion reduced the indicated thermal efficiency. Compared with the throttled spark ignition engine, the amount of residual exhaust flowing back into the intake port was greatly reduced at the early stage of the intake process. Consequently, it negatively influenced fuel evaporation and fuel–air mixing processes in the intake port of the port fuel injection spark ignition engine and decreased the flow of in-cylinder gases, which resulted in a low combustion rate. A new centrosymmetric helical valve is proposed in this article to improve the fuel–air mixing and combustion rate of the unthrottled spark ignition engine. The experiments demonstrate that the helical valve can generate a strong intake swirl at small intake valve lift. It helps to increase combustion rate and lower cycle-to-cycle variation, which improves indicated thermal efficiency and fuel economy of the unthrottled spark ignition engine at low load.

An artificial neural network developed for predicting of performance and emissions of a spark ignition engine fueled with butanol–gasoline blends

The engine experiments require multiple tests that are hard, time-consuming, and high cost. Therefore, an artificial neural network model was developed in this study to successfully predict the engine performance and exhaust emissions when a port fuel injection spark ignition engine fueled with n-butanol–gasoline blends (0–60 vol.% n-butanol blended with gasoline referred as G100-B60) under various equivalence ratio. In the artificial neural network model, compression ratio, equivalence ratio, blend percentage, and engine load were used as the input parameters, while engine performance and emissions like brake thermal efficiency, brake-specific fuel consumption, carbon monoxide, unburned hydrocarbons, and nitrogen oxides were used as the output parameters. In comparison between experimental data and predicted results, a correlation coefficient ranging from 0.9929 to 0.9996 and a mean relative error ranging from 0.1943% to 9.9528% were obtained. It is indicated that the developed artificial neural network model was capable of predicting the combustion of n-butanol–gasoline blends due to a commendable accuracy.

Cycle by cycle variations of LPG-gasoline dual fuel on a multi-cylinder MPFI gasoline engine

ABSTRACTCombustion stability of a multipoint port fuel injection spark ignition engine working on liquefied petroleum gas (LPG)-gasoline dual fuel mode of operation was analysed. LPG-gasoline ratio was varied from 0 to 100% by controlling the injector signals at wide open throttle condition and 3000 RPM. Increasing LPG ratio will give higher peak pressure and higher indicated mean effective pressure (IMEP) because of the higher flame propagation speed of LPG. The experiment showed that maximum pressure will occur nearer to top dead centre when compared to gasoline. Fluctuation in maximum pressure is higher for LPG and is minimum for 50% LPG. Time return map showed that combustion instabilibity will be more for 100% LPG and is less for 50% LPG. Coefficient of variation of IMEP and maximum pressure for gasoline is higher than LPG. With 100% LPG, NOx emission is almost three times that of gasoline. Hence it can be concluded that 50% LPG will give the better combustion characteristics when compared to other fuel blends.

Experimental investigation on combustion, performance, and emissions characteristics of butanol as an oxygenate in a spark ignition engine

Ethanol is known as the most widely used alternative fuel for spark-ignition engines. Compared to it, butanol has proved to be a very promising renewable fuel in recent years for desirable properties. The conjoint analysis on combustion, performance, and emissions characteristics of a port fuel injection spark-ignition engine fueled with butanol–gasoline blends was carried out. In comparison with butanol–gasoline blends with various butanol ratio (0–60 vol% referred as G100~B60) and conventional alcohol alternative fuels (methanol, ethanol, and butanol)–gasoline blends, it shows that B30 performs well in engine performance and emissions, including brake thermal efficiency, brake-specific fuel consumption, carbon monoxide, unburned hydrocarbons, and nitrogen oxides. Then, B30 was compared with G100 under various equivalence ratios ( Φ = 0.83–1.25) and engine loads (3 and 5-bar brake mean effective pressure). In summary, B30 presents an advanced combustion phasing, which leads to a 0.3%–2.8% lower brake thermal efficiency than G100 as the engine was running at the spark timing of gasoline’s maximum brake torque (MBT). Therefore, the sparking timing should be postponed when fueled with butanol–gasoline blends. For emissions, the lower carbon monoxide (2.3%–8.7%), unburned hydrocarbons (12.4%–27.5%), and nitrogen oxides (2.8%–19.6%) were shown for B30 compared with G100. Therefore, butanol could be a good alternative fuel to gasoline for its potential to improve combustion efficiency and reduce pollutant emissions.

Investigation of emissions characteristics of secondary butyl alcohol-gasoline blends in a port fuel injection spark ignition engine

Exhaust emissions especially from light duty gasoline engine are a major contributor to air pollution due to the large number of vehicles on the road. The purpose of this study is to experimentally analyse the exhaust pollutant emissions of a four-stroke port fuel spark ignition engines operating using secondary butyl alcohol–gasoline blends by percentage volume of 5% (GBu5), 10% (GBu10) and 15% (GBu15) of secondary butyl- alcohol (2-butanol) additives in gasoline fuels at 50% of wide throttle open. The exhaust emissions characteristics of the engine using blended fuels was compared to the exhaust emissions of the engine with gasoline fuels (G100) as a reference fuels. Exhaust emissions analysis results show that all of the blended fuels produced lower CO by 8.6%, 11.6% and 24.8% for GBu5, GBu10 and GBu15 respectively from 2500 to 4000 RPM, while for HC, both GBu10 and GBu15 were lower than that G100 fuels at all engine speeds. In general, when the engine was operated using blended fuels, the engine produced lower CO and HC, but higher CO2.