Showing papers on "Spark-ignition engine published in 2017"

Alcohol based automotive fuels from first four alcohol family in compression and spark ignition engine: A review on engine performance and exhaust emissions

Abstract: Alcohol fuels have some significant advantages over other alternative fuels, including the ability to work in existing engines as well as the capability to reduce greenhouse gas emissions. This paper analyses the performance and emissions of compression and spark ignition engine using of alcohol fuels from the first aliphatic alcohol family; methanol, ethanol, propanol and butanol. The literature relevant to methanol, ethanol, propanol and butanol was reviewed and summarized to demonstrate its viability as an alternative fuel. The fuel properties of methanol, ethanol, propanol and butanol present the most important properties that allow such fuels as suitable candidates as an alternative fuel for compression and spark ignition engines. The performance and engine emissions indicators such as brake torque, brake power, BTE, BSFC NOx, PM, CO, CO2, HC and soot have been evaluated regarding tone at diesel and gasoline fuels. The results showed that alcohol fuels give different results to engine performance and emissions. Surprisingly, some research yield favorable results to the alcohol as compared to neat diesel and gasoline fuels. It can be concluded that methanol, ethanol, propanol and butanol are capable of reducing harmful engine exhaust emissions, however,at the expense of lower engine performance characteristics.

Laminar flame speed correlations for methane, ethane, propane and their mixtures, and natural gas and gasoline for spark-ignition engine simulations:

Abstract: The laminar flame speed plays an important role in spark-ignition engines, as well as in many other combustion applications, such as in designing burners and predicting explosions. For this reason,...

Performance and emission characteristics of a spark ignition engine fuelled with butanol isomer-gasoline blends

Abstract: The heavy reliance on petroleum-derived fuels such as gasoline in the transportation sector is one of the major causes of environmental pollution. For this reason, there is a critical need to develop cleaner alternative fuels. Butanol is an alcohol with four different isomers that can be blended with gasoline to produce cleaner alternative fuels because of their favourable physicochemical properties compared to ethanol. This study examined the effect of butanol isomer-gasoline blends on the performance and emission characteristics of a spark ignition engine. The butanol isomers; n-butanol, sec-butanol, tert-butanol and isobutanol are mixed with pure gasoline at a volume fraction of 20 vol%, and the physicochemical properties of these blends are measured. Tests are conducted on a SI engine at full throttle condition within an engine speed range of 1000–5000 rpm. The results show that there is a significant increase in the engine torque, brake power, brake specific fuel consumption and CO2 emissions with respect to those for pure gasoline. The butanol isomers-gasoline blends give slightly higher brake thermal efficiency and exhaust gas temperature than pure gasoline at higher engine speeds. The iBu20 blend (20 vol% of isobutanol in gasoline) gives the highest engine torque, brake power and brake thermal efficiency among all of the blends tested in this study. The isobutanol and n-butanol blend results in the lowest CO and HC emissions, respectively. In addition, all of the butanol isomer-gasoline blends yield lower NO emissions except for the isobutanol-gasoline blend.

Integral Length Scales and Time Scales of Turbulence in an Optical Spark-Ignition Engine

Abstract: In-cylinder air flow structures are known to play a major role in mixture preparation and flame development in spark-ignition engines. In this paper both LDV and PIV measurements were undertaken in an optical spark-ignition at 1500 RPM 0.5 bar inlet plenum pressure. One of the primary PIV planes was vertical cutting through the centrally located spark plug (tumble plane) inside the pentroof at ignition timing. The other plane was horizontal inside the pentroof 1 mm below the spark plug LDV was conducted 1 mm below the spark plug on a line from inlet to exhaust but also on a lower line 14 mm below the spark plug. In-cylinder PIV data at specific crank angles in the intake and compression strokes were also analysed on the central tumble plane and on a horizontal plane 14 mm below the spark plug. The combination of both techniques allowed high spatial and temporal resolution as the two data sets complemented each other to provide details of mean flow and turbulence characteristics on different levels, aiming ultimately for quantification of integral time scales and length scales. LDV cycle-resolved analysis distinguished between the classic approach of using the time integral of the autocorrelation function to obtain the integral time scale and a high-frequency cut-off analysis to obtain high- and low-frequency fluctuations about an in-cycle mean.

Performance analysis of ethanol–gasoline blends on a spark ignition engine: a review

Abstract: Alternative fuels have an important role to play for both spark ignition and compression ignition engines, the prime reasons being the need to trim down the dependency on gasoline as a fuel and its economic aspects. Many investigations have primarily focused on using alternative fuels to see the diminishing effect on fuel consumption. The aim of this review is to study and analyze the range of opportunities and future prospects of introducing blends of gasoline–ethanol, gasoline with all other alcohols derivative and subsequent alternative fuels in varying percentage ratios in the existing spark ignition engines by diagnosing various aspects such as air–fuel ratio, operating cylinder pressure, ignition timing and compression ratio related to the performance parameters only. Ethanol blends in lower proportions showed an increment in the range of 2.31–4.16% for the engine torque and 0.29–4.77% for brake power. Brake specific fuel consumption (BSFC) increased for higher volume of ethanol content in t...

Spark discharge ignition process in a spark-ignition engine using a time series of spectra measurements

Abstract: The spark discharge ignition process was investigated using simultaneous temperature measurements of the spark discharges and the initial flame kernel. We were able for the first time to measure a time series of emission spectra from the spark discharge and initial flame kernel inside a spark-ignition engine using a spectrometer coupled with a spark plug and optical fiber. The plasma vibrational temperature of the spark discharge can be measured using time series emission spectra from the electrically excited CN * violet band system. The gas rotational temperature of the initial flame kernel can also be measured using emission spectra from OH * radicals (P and R branches). Simultaneously, visualization of the spark discharge and a time series of emission spectra inside a spark-ignition engine were performed under homogeneous mixture conditions, to eliminate the effects of stratification of temperature and mixture concentrations around the spark plug. We discuss thermal energy transfer from the spark discharge to the combustible mixture. The main conclusions that can be drawn from this study are as follows. CN * emission can be detected from the spark discharge, visualized using a high-speed camera during the arc discharge phase. Our results confirmed that the plasma temperature of the spark discharge was nearly 6800 K and that thermal energy was transferred from the spark plasma channel to the combustible mixture. The gas temperature of the initial flame kernel approached that of the adiabatic flame temperature.

Influence of plastic oil with ethanol gasoline blending on multi cylinder spark ignition engine

Abstract: Energy consumption is becoming the index of country development. Transportation sector is occupied the second position in total energy consumption. Traditional energy sources are obliterating out and leaving carbon foot prints on environment. Across the world plastic consumption and its disposal is increasing at exponential rate. The current research is aimed to utilize this plastic waste as an input for engine running in the form of plastic pyrolysis oil (PPO). Experiments are conducted with PPO on multi cylinder Maruti 800 petrol engine to evaluate the performance and emissions characteristics. The gasoline is blended with 15% PPO and with and without ethanol additive at 5%. The performance and emissions result of plastic oil blend is compared with pure petrol and ethanol added blend. The experimental outcomes clears, that the brake thermal efficiency of 15PPO is lower than that of pure petrol while the NOx emissions are substantially increased. Therefore, ethanol is added as an additive to control the NOx emissions, engine performance is improved compared to pure petrol and 15PPO. Emissions like CO, NO x are significantly controlled.

Effect of injection timing on combustion and soot formation in a direct injection spark ignition engine fueled with butanol

Abstract: Ever tighter restrictions on pollutant emissions, energy security and a continuous drive for improving fuel economy have extended the range of application for direct injection in spark ignition eng...

Effect of coolant temperature on air–fuel mixture formation and combustion in an optical direct injection spark ignition engine fueled with gasoline and butanol

Abstract: Diversification of the energy mix and the drive for increasing security of supply have extended the use of alternative fuels in internal combustion engines. Butanol is a viable energy source for spark ignition (SI) power units featuring higher energy density and compatibility with existing systems. The present work investigated the use of n-butanol in an optically accessible wall guided direct injection SI engine, operated at low load, as well as wide open throttle. Engine speed and injection pressure were kept constant, while coolant temperature was alternated between two values, so as to simulate cold-start and fully warmed-up conditions. In-cylinder pressure and exhaust gas emission measurements were coupled with optical results obtained through UV–visible flame visualization and 2D chemiluminescence. This allowed a more detailed insight into the occurrence of diffusive flames near the piston surface and an analysis of flame front propagation, as well as its morphology. The correlation of thermodynamic data and flame imaging with band-pass filters for recording the spatial distribution of the OH radical, soot precursors and carbonaceous structures gave information on the evolution of chemical species during combustion. While at low load the alcohol performed slightly better compared to gasoline, at wide open throttle the opposite was recorded. The effect of coolant temperature was more evident for butanol. These observations were correlated to the presence of liquid fuel film on the piston crown, which resulted in slower flame propagation and higher related emissions for the alcohol.