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In the present investigation, experiments were conducted in wide open throttle condition (WOT) for different speed ranging from 1400 rpm to 1800 rpm at an interval of 200 on a single-cylinder four-stroke port-injected; spark-ignition engine. The engine fueled with equi-volume blend of methanol/gasoline was tested for different ignition timing and i...
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In this study, the availability of methanol instead of ethanol was investigated in terms of performance, emission and combustion characteristics. The experiments were conducted in a single cylinder, four-stroke SI engine for different engine speeds at full engine load. Test fuels were prepared by 10% ethanol and methanol addition into gasoline. Acc...
This study assessed the performance and emissions characteristics of a single cylinder, 2-stroke motorcycle spark ignition engine (Esoo 150 cc) utilising clay-catalytically produced distilled waste plastic pyrolysis oil (DWPPO) fuel. The clay catalyst and fuel properties were analysed using established standard testing procedures. The engine perfor...
The throttle mechanism, a regulatory technique of engine output, is accompanied by a loss of some energy. The effect of intake air throttling on the performance and emissions of a multi-cylinder spark ignition gasoline engine was experimentally investigated. The engine was coupled to a hydraulic dynamometer equipped with a customized cooling system...
The present paper presents a study whose objective is to determine the performance parameters of an external mixture formation and spark-ignition engine when running on methane fuel. The experiments were carried out using optimum adjusting parameters for engine operation on methane and gasoline fuels. The parameters measured and determined are: bra...
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Ethanol fuel, as a bioproduct has become a common option to address the issue of energy sustainability. However, the current method of blending ethanol with gasoline does not take the full advantages of ethanol fuel such as its high octane number and great latent heat which potentially allow the increase of the compression ratio and improvement of...
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... Whereas with SOI advancing, cylinder pressure increases during the compression stroke and leads to increase in the compression work as a negative work [33]. It is suggested that for the fuel with more fastburning ability than gasoline, a slightly retarded (shifting toward TDC) ignition is preferred, as it reduces the negative work against the fast fuel burn and enables rapid rise of pressure at compression region [34]. SOI has to vary with equivalence ratio, compression ratio and blending ratio. ...
... However, delayed ignition results in combustion instabilities [39][40][41], increasing CoV imep , and heat losses. Therefore, the ignition retard under a slight compromise with performance is insufficient to control NO x within permissible boundar [42,43]. Another NO x control technique, exhaust gas recirculation (EGR), is up-and-coming and widely considered the most effective [44][45][46]. ...
... A high hydrogen-to-carbon ratio and a single molecule structure limit the specific carbon emission [15]. Nathan Prasad and Kumar [16] showed a significant reduction in net carbon emission for 50% methanol blending, and a proper ignition led to a considerable reduction in NO x emissions. However, Mishra et al. [17] had a slightly different analysis; they observed a slight increase in CO 2 emissions despite less CO, HC, and NO x . ...
Bio-methanol has recently interested researchers looking for a suitable alternative due to its low carbon/hydrogen (C/H) ratio. Adding methanol to Autogas could thereby improve combustion while lowering emissions. In the present investigation, testing is conducted at a compression ratio of 14:1 on various fuel ratios (55/45 to 75/25 with a 5% change) of methanol/Autogas with ignition timing ranging from 28°CA bTDC to 14°CA bTDC. The results indicate improvements due to the addition of 65% methanol. Improved brake thermal efficiency (BTE) by 6.27%, peak pressure (Pmax) by 0.36%, heat release rate (HRRmax), peak temperature (Tmax) by 0.89%, and rise in exhaust gas temperature (EGT). Simultaneously, combustion duration, HC & CO emissions, and the coefficient of variations in indicated mean effective pressure (CoVIMEP) are reduced. With methanol, the volumetric efficiency (ηvol) improves continuously. Optimal ignition timing is shown to advance with increasing methanol concentration. With ignition retard, the flame development phase (CA10) decreases by 1.7%/2°CA ignition retard, whereas the flame propagation phase (CA10–90) decreases to a minimum and then increases. Due to combustion instability, ignition retard increases the Cyclic variation and CoVIMEP, while Pmax, HRRmax, Tmax, and BTE increase to a maximum and then drop. Ignition retard is an effective way of reducing NOx emissions, although CO and HC emissions increase significantly. Due to reduced carbon supply, carbon emissions are extremely low even at higher methanol concentrations than Autogas-rich fuel. NOx emissions are also extremely low (62.5 % of the ignition angle at 24°CA), revealing that a higher methanol ratio could be used with minimal risk of power loss.
... The peak in-cylinder combustion temperature was dropped by the retarded ignition of later than −17.3 • CA under the given equivalence ratio conditions; additionally, the corresponding crank angle was delayed. Regarding reciprocating engines [66], peak incylinder temperature was increased by advancing ignition timing; however, the ORP engine presented a different pattern, resulting from the fact that significant early ignition would limit the flame developments due to the structures of ignition systems (see Figure 3). The ignition timing effects on the in-cylinder temperature at the end of expansion stroke were reverse to that of peak in-cylinder temperature. ...
The application of hydrogen fuel in ORP engines makes the engine power density much higher than that of a reciprocating engine. This paper investigated the impacts of combustion characteristics, energy loss, and NOx emissions of a hydrogen-fuelled ORP engine by ignition timing over various equivalence ratios using a simulation approach based on FLUENT code without considering experiments. The simulations were conducted under the equivalence ratio of 0.5~0.9 and ignition timing of −20.8~8.3 °CA before top dead centre (TDC). The engine was operated under 1000 RPM and wide-open throttle condition which was around the maximum engine torque. The results indicated that significant early ignition of the ORP engine restrained the flame development in combustion chambers due to the special relative positions of ignition systems to combustion chambers. In-cylinder pressure evolutions were insensitive to early ignition. The start of combustion was the earliest over the ignition timing of −17.3 °CA for individual equivalence ratios; the correlations of the combustion durations and equivalence ratios were dependent on the ignition timing. Combustion durations were less sensitive to equivalence ratios in the ignition timing range of −14.2~−11.1 °CA before TDC. The minimum and maximum heat release rates were 15 J·(°CA)−1 and 22 J·(°CA)−1 over the equivalence ratios of 0.5 and 0.9, respectively. Indicated thermal efficiency was higher than 41% for early ignition scenarios, and it was significantly affected by late ignition. Energy loss by cylinder walls and exhaust was in the range of 10%~16% and 42%~58% of the total fuel energy, respectively. The impacts of equivalence ratios on NOx emission factors were affected by ignition timing.
This study expresses the core elements associated with the various types of fuels used in vehicles functional in the present day. The exploration of chemicals such as methanol and others have also been conducted in an accurate manner to gain objective insights and outlooks in the study. The social and economic impacts of methanol-gasoline blends in engines can be complex in nature that depend on various factors such as the concentration levels of methanol in the blend, the availability of fuel, and public perception, among others. Further research and analysis as conducted in the study have been useful in understanding the potential impacts of methanol-gasoline blends across global spheres.
To enrich the knowledge and understanding of the application effect of methanol fuel In the current engine, the Influence of methanol-gasoline blended fuel containing 10 %, 20 % and 30 % methanol addition (M10, M20 and M30) on the engine performance, combustion and emissions were studied on a turbocharged and direct injection engine with original control system and control parameters. The results showed that at the conditions with low speed, the peak heat release rate and cylinder pressure were decreased by the use of blended fuel while it shown an increased peak combustion pressure and heat release rate at high speed. Meanwhile, the combustion center of blended fuel was obviously different from gasoline and its optimal value, and the combustion variation was increased at low load. The fuel consumption lifted continuously with the increase of methanol addition ratio, and the equivalent fuel consumption of M10 and M20 also was higher than that of pure gasoline. For NOx emissions, although it has been improved continuously for M10, M20 and M30 under the higher engine load, the higher emissions were obtained for M10 and M20 at lower load. In addition, compared with gasoline fuel, the whole particle distribution curve and number concentration was significantly deteriorated with methanol addition.
Opposed rotary piston engines have the characteristics of high-power density and simple mechanisms. The applications of hydrogen fuel to internal combustion engines significantly are without carbon dioxide emission, alleviating the global warming. In this paper, hydrogen fuel was asymmetrically injected into combustion chambers to increase hydrogen penetration distance via; in the meantime, the engine performance and nitrogen monoxide (NO) emission with different ignition timing are explored by numerical simulation method. The symmetrical fuel injection scenario was provided as a baseline. In the scenarios of asymmetrical fuel injection, the engine had the best hydrogen injector position and ignition timing. Peak in-cylinder pressure Pmax reached 56.0 bar under ignition timing ti of −14.2° CA before top dead centre (bTDC) and hydrogen injector position (θ2) of 60.5°; in the meantime, heat loss rate HL and heat release rate Qr reached maximum values. Compared with the symmetric fuel injection engine, the peak NO emission of the asymmetric fuel injection engine was reduced by 15%. The proportions of energy loss by cylinder walls of asymmetric fuel injection engine were low and showed low dependency on ignition timing and hydrogen injector layout. Additionally, the asymmetric hydrogen injection structure makes hydrogen distribute evenly in the combustion chamber.
In the present paper, an experimental investigation has been performed under variable CR and 1400&1800RPM speed at a fixed spark timing of 24ºCA BTDC under wide-open throttle conditions. The hydrogen blending is performed based on energy fractions from 5% to 21% of the total fuel energy. With increasing compression ratio (CR), the flame development gets faster, and the flame propagation speed improves, leading to a short combustion period. Similarly, increasing hydrogen fraction improves combustion, resulting in a rapid rise in pressure and temperature. Despite a 13.64% decrease in volumetric efficiency from 5% to 21% hydrogen fraction at 1400 and 1800 RPM, BP and BTE increased by 16.89% and 33%, respectively. The slow-burning properties of NH3 extend the combustion period, resulting in a long-delayed burning period. As a result, the temperature of the low-hydrogen fraction of the exhaust gas is higher. As the hydrogen fraction and CR increase, this effect decreases, resulting in lower EGT. The hydrogen addition increases the peak temperature; therefore, NOx increases continuously with increasing hydrogen despite reducing ammonia. Ammonia is a key element used to reduce NOx from vehicles. A practical solution for controlling the NOx due to the ammonia/hydrogen blend is selective catalytic reduction (SCR).
Primary alcohols such as methanol, ethanol, and butanol have exhibited excellent potential as possible alternative fuels for spark ignition (SI) engines because they are renewable, cleaner and safer to store and transport. However, it remains important to investigate the technical feasibility of adapting these primary alcohols in existing SI engines. In this research, a multi-point port fuel injection (MPFI) system equipped SI engine was used for assessing and comparing the combustion, performance, and emission characteristics of various alcohol-gasoline blends (gasohols) vis-à-vis baseline gasoline. The experiments were performed for different engine loads at rated engine speed. Experimental results exhibited relatively superior combustion characteristics of the engine fueled with gasohol than the baseline gasoline, especially at medium engine loads. Among different test fuels, the methanol-gasoline blend (GM10) exhibited relatively more stable combustion characteristics than the ethanol-gasoline blend (GE10) and butanol-gasoline blend (GB10). In this study, relatively superior engine performance of the gasohol-fueled engine was observed at all engine loads and speeds. GB10 exhibited the highest brake thermal efficiency (BTE), followed by GM10 amongst all test fuels. The effect of improved combustion was also reflected in the emission characteristics, which exhibited that GB10 emitted relatively lower carbon monoxide (CO) and hydrocarbons (HC) than other test fuels. GB10 emitted relatively higher nitrogen oxides (NOx) than GM10 and GE10. Unregulated emission results exhibited that the engine fueled with gasohols emitted relatively lower sulfur dioxide (SO2), ammonia (NH3), and various saturated and unsaturated HCs than the baseline gasoline. The GM10-fuelled engine was relatively more effective in reducing unregulated emissions among all test fuels. This study concluded that methanol and butanol blending with gasoline resulted in superior engine performance and reduced harmful emissions in MPFI transport engines. This offered an excellent option to displace fossil fuels partially and reduce emissions simultaneously.
