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The purpose of this paper is to compare the combustion characteristics, including the combustion pressure, heat release rate (HRR), coefficient of variation (COV) of indicated mean effective pressure (IMEP), flame development period and combustion duration, of aviation kerosene fuel, namely, rocket propellant 3 (RP-3), and gasoline on a two-stoke spark ignition engine.

This paper is an experimental investigation using a bench test to reflect the combustion performance of two-stroke spark ignition unmanned aerial vehicle (UAV) engine on gasoline and RP-3 fuel.

Under low load conditions, the combustion performance and HRR of burning RP-3 fuel were shown to be worse than those of gasoline. Under high load conditions, the average IMEP and the COV of IMEP of burning RP-3 fuel were close to those of gasoline. The difference in the flame development period between gasoline and RP-3 fuel was similar.

Gasoline fuel has a low flash point, high-saturated vapour pressure and relatively high volatility and is a potential hazard near a naked flame at room temperature, which can create significant security risks for its storage, transport and use. Adopting a low volatility single RP-3 fuel of covering all vehicles and equipment to minimize the number of different devices with the use of a various fuels and improve the application safeties.

Most two-stroke spark ignition UAV engines continue to combust gasoline. A kerosene-based fuel operation can be applied to achieve a single-fuel policy.

The purpose of this study is to assess the performance of fuel blends containing ethanol and gasoline in spark ignition engines. The aim is to explore alternative fuels that can enhance performance while minimizing or eliminating adverse environmental impacts, particularly in the context of limited fossil fuel availability and the need for sustainable alternatives.

The authors used the Ricardo Wave software to evaluate the performance of fuel blends with varying ethanol content (represented as E0, E10, E25, E40, E55, E70, E85 and E100) in comparison to gasoline. The assessment involved different composition percentages and was conducted at various engine speeds (1,500, 3,000, 4,500 and 6,000 rpm). This methodology aims to provide a comprehensive understanding of how different ethanol-gasoline blends perform under different conditions.

The study found that, across all fuel blends, the highest brake power (BP) and the highest brake-specific fuel consumption (BSFC) were observed at 6,000 rpm. Additionally, it was noted that the presence of ethanol in gasoline fuel blends has the potential to increase both the BP and BSFC. These findings suggest that ethanol can positively impact the performance of spark-ignition engines, highlighting its potential as an alternative fuel.

This research contributes to the ongoing efforts in the automotive industry to find sustainable alternative fuels. The use of Ricardo Wave software for performance assessment and the comprehensive exploration of various ethanol-gasoline blends at different engine speeds add to the originality of the study. The emphasis on the potential of ethanol to enhance engine performance provides valuable insights for motor vehicle manufacturers and researchers working on alternative fuel solutions.

To prolong engine life and reduce exhaust pollution caused by gasoline engines, the aim of this paper was to compare the lubrication properties of biofuel (ethanol) blends and pure unleaded gasoline.

Biofuels with a concentration of 0, 1, 2, 5 and 10 per cent were added to unleaded gasoline to form ethanol-blended fuels named E0, E1, E2, E5 and E10. Next, the ethanol-blended fuels and unleaded gasoline were used to power engines to facilitate comparisons between the pollution created from exhaust emissions.

Using ethanol as a fuel additive in pure unleaded gasoline improves engine performance and reduces exhaust emissions. Because bioethanol does not contain lead but contains low aromatic and high oxygen content, it induces more complete combustion compared with conventional unleaded gasoline.

Using biofuels as auxiliary fuel reduces environmental pollution, strengthens local agricultural economy, creates employment opportunities and reduces demand for fossil fuels.

FUEL quality not only has a very great influence on engine operation and maintenance, but it is also one of the most important factors controlling engine development. Gasolines used as internal‐combustion engine fuels possess many physical characteristics, each of which has some practical influence upon the operation and running of engines. The selection of the most suitable fuels for aircraft engines demands a knowledge of these fuel characteristics, which are discussed below.

The purpose of this paper is to present results of practical experience of cold starting a gasoline engine on low volatility fuel suitable for unmanned aerial vehicle (UAV) deployment.

Experimental research and development is carried out via dynamometer testing of systems capable of achieving cold start of a spark ignition UAV engine on kerosene JET A-1 fuel.

Repeatable cold starts have been satisfactorily achieved at ambient temperatures of 5°C. The approximate threshold for warm engine restart has also been established.

For safety and supply logistical reasons, the elimination of the use of gasoline fuel offers major advantages not only for UAVs but also for other internal combustion engine-powered equipment to be operated in military theatres of operation. For gasoline crankcase-scavenged two-stroke cycle engines, this presents development challenges in terms of modification of the lubrication strategy, achieving acceptable performance characteristics and the ability to successfully secure repeatable engine cold start.

The majority of UAVs still operate on gasoline-based fuels. Successful modification to allow low volatility fuel operation would address single fuel policy objectives.

This paper aims to compare the conditions of in-service oils from diesel and gasoline engines, with focus on nitration.

Oil conditions of seven engine oil samples from five diesel-fueled vehicles and nine oil samples from eight gasoline-fueled vehicles with total mileage ranging from 13,600 to 30,000 km were determined via Fourier-transform infrared spectroscopy as well as neutralization number (NN) and total base number titration.

Chemical deterioration was characterized by significant differences in oxidation, nitration, NN increase and residual aminic antioxidant contents.

Submitted in connection with the Special Issue, “Young Tribologists – Insights into the work of the new generation”.

Uncovering differences in the oil degradation of oils from gasoline and diesel engines enables improved condition-based maintenance strategies and the prediction of oil condition dependent tribological performance.

Homogeneous charge compression ignition (HCCI) engine is an advanced combustion method to use alternate fuel with higher fuel economy and, reduce NOX and soot emissions. This paper aims to investigate the influence of ethanol fraction (ethanol plus gasoline) on dual fuel HCCI engine performance.

In this study, the existing CI engine is modified into dual fuel HCCI engine by attaching the carburetor to the inlet manifold for the supply of ethanol blend (E40/E60/E80/E100). The mixture of ethanol blend and the air is ignited by diesel through a fuel injector into the combustion chamber at the end of the compression stroke. The experiments are conducted for high load conditions on the engine i.e. 2.8 kW and 3.5 kW maximum output power for 1,500 constant rpm.

It is noticed from the experimental results that, with an increase of ethanol in the blends, ignition delay (ID) increases and the start of combustion is retarded. It is noticed that E100 shows the highest ID and low in-cylinder pressure; however, E40 shows the lowest ID compared to higher fractions of ethanol blends. An increase in ethanol proportion reduces NOX and smoke opacity but, HC and CO emissions increase compared to pure diesel mode engine. E100 plus diesel dual-fuel HCCI engine shows the highest brake thermal efficiency compared to remaining ethanol blends and baseline diesel engine.

This experimental study concluded that E100 plus diesel and E80 plus diesel gave optimum dual fuel HCCI engine performance for 2.8 kW and 3.5 kW rated power, respectively.

Considering pollution problems and the energy crisis today, investigations have been concentrated on lowering the concentration of toxic components in combustion products and decreasing fossil fuel consumption by using renewable alternative fuels. In this work, the effect of ethanol addition to gasoline on the exhaust emissions of a spark ignition engine at various speeds was established. Ethanol was extracted from groundnut seeds using fermentation method. Gasoline was blended with 20 - 80% of the extracted ethanol in an interval of 20%. Results of the engine test indicated that using ethanol-gasoline blended fuels decreased carbon monoxide (CO) and hydrocarbon (HC) emissions as a result of the lean- burn effects caused by the ethanol, and the carbon dioxide (CO₂) emission increased because of a near complete combustion. Finally, the results showed that blending ethanol in a proportion of 40% with gasoline can be used as a supplementary fuel in modern spark ignition engines as it is expected that the engine performs at its optimum in terms of air toxic pollutants reduction, by virtue of that mix.

The purpose of this paper is to analyze and compare the performances of novel roadable personal air vehicle (PAV) concepts that meet established operational requirements with different types of engines.

The vehicle configuration was devised considering the dimensions and operational restrictions of the roads, runways and parking lots in South Korea. A folding wing design was adopted for road operations and parking. The propulsion designs considered herein use gasoline, diesel and hybrid architectures for longer-range missions. The sizing point of the roadable PAV that minimizes the wing area was selected, and the rate of climb, ground roll distance, cruise speed and service ceiling requirements were met. For various engine types and mission profiles, the performances of differently sized PAVs were compared with respect to the MTOW, wing area, wing span, thrust-to-weight ratio, wing loading, power-to-weight ratio, brake horsepower and fuel efficiency.

Unlike automobiles, the weight penalty of the hybrid system because of the additional electrical components reduced the fuel efficiency considerably. When the four engine types were compared, matching the total engine system weight, the internal combustion (IC) engine PAVs had better fuel efficiency rates than the hybrid powered PAVs. Finally, a gasoline-powered PAV configuration was selected as the final design because it had the lowest MTOW, despite its slightly worse fuel efficiency compared to that of the diesel-powered engine.

Although an electric aircraft powered only by batteries most capitalizes on the operating cost, noise and emissions benefits of electric propulsion, it also is most hampered by range limitations. Air traffic integration or any safety, and noise issues were not accounted in this study.

Aircraft sizing is a critical aspect of a system-level study because it is a prerequisite for most design and analysis activities, including those related to the internal layout as well as cost and system effectiveness analyses. The results of this study can be implemented to design a PAV.

This study can contribute to the establishment of innovative PAV concepts that can alleviate today’s transportation problems.

This study compared the sizing results of PAVs with hybrid engines with those having IC engines.