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The European Union has defined legally binding CO2-fleet targets for new cars until 2030. Therefore, improvement of fuel economy and carbon dioxide emission reduction is becoming one of the most important issues for the car manufacturers. Today’s conventional car powertrain systems are reaching their technical limits and will not be able to meet future CO2 targets without further improvement in combustion efficiency, using low carbon fuels (LCF), and at least mild electrification. This paper demonstrates a highly efficient and performant combustion engine concept with a passive pre-chamber spark plug, operating at stoichiometric conditions and powered with liquefied petroleum gas (LPG). Even from fossil origin, LPG features many advantages such as low carbon/hydrogen ratio, low price and broad availability. In future, it can be produced from renewables and it is in liquid state under relatively low pressures, allowing the use of conventional injection and fuel supply components.

This work investigates the development of a novel series hybrid architecture utilizing a single cylinder opposed piston engine. The opposed piston engine presents unique benefits in a hybrid architecture such as its lower heat transfer due to a favorable surface area to volume ratio and lack of a cylinder head, as well as the thermodynamic benefits of two stroke operation with uniflow scavenging. A particular focus of this effort is the work extraction efficiency of two design concepts. The first design concept utilizes a geartrain to couple the crankshafts of the engine in a conventional manner, providing a single power take-off for coupling to an electric motor/generator. In this design, the large inertia of the geartrain dampens the speed fluctuation of the single cylinder engine, reducing the peak torque required to for the electric machine. However, the friction losses caused by the geartrain limit the maximum work extraction efficiency.

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Abstract The Formula SAE (FSAE) is an international engineering competition where a Formula style race car is designed and built by students from worldwide universities. According to FSAE regulation, an air restrictor with circular cross section of 20 mm for gasoline-fuelled and 19 mm for E-85-fuelled vehicles is to be incorporated between the throttle valve and engine inlet. The sole purpose of this regulation is to limit the airflow to the engine used. The only sequence allowed is throttle valve, restrictor and engine inlet. A new approach of combining ram theory and acoustic theory methods are investigated to increase the performance of the engine by designing an optimized intake runner for a particular engine speed range and an optimized plenum volume in this range. Engine performance characteristics such as brake power, brake torque and volumetric efficiency are taken into considerations.

Numerical calculation based on finite element method are carried out to calculate the temperature field in an adiabatic diesel engine piston having diameter. 127 mm and made of aluminum alloy. The engine cylinder wall have the coated externally by a thin layer of very high grade ceramic insulating material. The isothermic distribution in the piston body and the heat flow rates to the cooling media at different loads have been depicted for both cases with and without insulation coating. The paper first reviews the current state of development of ‘adiabatic’ diesel engine in Europe, U.S.A and the Japan. This review section is followed by a brief description of the common element of hostile features, then comes the experimental program on thermally insulated components for single cylinder engine in the research center of Tabriz and finally by a theoretical section dealing with the performance potential of composed engine schemes based on ‘adiabatic’ engine operation.

Authors have experimented the effects of cooling water temperature on the particulate emission characteristics from a high speed DI diesel engines. A single cylinder small high speed DI diesel engine is operated under various engine speed and load conditions. Cooling water temperature is varied from 313 K (40 °C) to 363 K (90 °C). Particulate is collected using a single stage full size dilution tunnel. Dry soot and SOF emissions are measured, as well as total particulate. SOF increases when the cooling water temperature decreases, as well as HC increases. SOF also increases as load decreases. This suggests that the SOF emits at the cold starting and warming up periods. This also suggests that the SOF can be reduced by increasing cooling water temperature. IT IS IMPORTANT TO CLARIFY the effects of cooling water temperature on the particulate emission.

A single cylinder engine was used to collect engine combustion chamber deposits insitu, and to investigate the influence of fuel composition on combustion chamber deposit formation. High-boiling aromatic compounds were found to contribute greatly to deposit formation, while olefinic compounds did not show any significant deposit-forming tendencies. In a low surface temperature regime, deposit formation increased with boiling point of aromatic dopants added to the base fuel. Various analytical techniques (FTIR, GC/MS, EPMA, SEM) were utilized to characterize carbonaceous deposits in an early stage of formation. Oxidized hydrocarbon species (ketones, carboxylic acids, lactones, esters), metal carboxylates, and decomposition products of oil additives were found to be major building blocks of deposits. The oxidized hydrocarbon species formed in a preflame region are condensed/adsorbed on a relatively cold surface to form combustion chamber deposits.

This paper is concerned with a new type of non-uniform velocity balancer appling to the single cylinder engine. A conventional balancer rotate in an uniform velocity,while the new one rotate in a non-uniform velocity. A non-uniform velocity rotation is given by the eccentric gear installed balancer shaft. It is recognized that the moderate eccentricity of gear train is existed for reducing the exciting force and its effect is remarkable.

Additive manufacturing was used to fabricate a head for an automotive-scale single-cylinder engine operating on natural gas. The head was consisted of a bimetallic composition of stainless steel and bronze. The engine performance using the bimetallic head was compared against the stock cast iron head. The heads were tested at two speeds (1200 and 1800 rpm), two brake mean effective pressures (6 and 10 bar), and two equivalence ratios (0.7 and 1.0). The bimetallic head showed good durability over the test and produced equivalent efficiencies, exhaust temperatures, and heat rejection to the coolant to the stock head. Higher combustion temperatures and advanced combustion phasing resulted from use with the bimetallic head. The implication is that with optimization of the valve timing, an efficiency benefit may be realized with the bimetallic head.

Abstract This article presents a misfire detection index for motorcycles with a single-cylinder engine. Compared with automobiles with multicylinder engines, attempts to diagnose single-cylinder motorcycle engine misfires have been rare. Therefore, a new index, detrended engine rpm amplitude (DERA), is proposed to detect misfires using tooth time measured by the crankshaft position sensor; thus, there is no additional cost for the DERA index. This index is defined as the difference between the squares of the maximum and minimum values of engine speed (rpm) detrended by the engine speed trend line, instead of the linear regression method. Thus calculating the DERA index becomes simple and fast, and it is advantageous to reduce the computation time. Here the engine speed trend line is a line connecting the engine speeds at the first teeth of the current and subsequent cycles.

The reduction of carbon footprint of compression ignition engines for road transport makes it necessary to search for clean fuels alternative to diesel and to evaluate them under engine conditions. For this reason, in this paper, the combustion behaviour of different blends of synthetic fuels has been analyzed in an optical single cylinder engine of Medium Duty size (0,8 liters per cylinder) by means of optical techniques. The aim is to evaluate the effect of synthetic fuels, both partly or completely fossil diesel, in terms of combustion behaviours and soot formation. Therefore, different blends of oxymethylene dimethyl ether (OMEX) with diesel and neat hydrotreated vegetable oil (HVO) were studied. A conventional common rail injection system and a single injection strategy was used. In addition, special care was taken to ensure that conditions inside the engine cylinder at the injection start were as close as possible to the conditions used in previous studies.

Within the Cluster of Excellence “Tailor-Made Fuels from Biomass” (TMFB) at the RWTH Aachen University, two novel biogenic fuels, namely 1-octanol and its isomer dibutyl ether (DBE), were identified and extensively analyzed in respect of their suitability for combustion in a Diesel engine. Both biofuels feature very different properties, especially regarding their ignitability. In previous works of the research cluster, promising synthesis routes with excellent yields for both fuels were found, using lignocellulosic biomass as source material. Both fuels were investigated as pure components in optical and thermodynamic single cylinder engines (SCE). For 1-octanol at lower part load, almost no soot emission could be measured, while with DBE the soot emissions were only about a quarter of that with conventional Diesel fuel. At high part load (2400 min-1, 14.8 bar IMEP), the soot reduction of 1-octanol was more than 50% and for DBE more than 80 % respectively.

Abstract This article presents a comparative study between two camshafts systems adapted to the single cylinder engine of a Supermileage vehicle in a fuel economy perspective. One system is from a Honda AF70E engine and the other is a new design. The new camshaft system was improved for fuel economy by developing a new camshaft that enhances volumetric efficiency while reducing friction losses. The comparison was made by measuring the efficiency of the engine in the speed range where the engine was used by the Supermileage vehicle and a calculation was made to show which of the configuration is best for the vehicle.

Abstract Turbocharging can provide a low cost means for increasing the power output and fuel economy of an internal combustion engine. Currently, turbocharging is common in multi-cylinder engines, but due to the inconsistent nature of intake air flow, it is not commonly used in single-cylinder engines. In this article, we propose a novel method for turbocharging single-cylinder, four-stroke engines. Our method adds an air capacitor-an additional volume in series with the intake manifold, between the turbocharger compressor and the engine intake-to buffer the output from the turbocharger compressor and deliver pressurized air during the intake stroke. We analyzed the theoretical feasibility of air capacitor-based turbocharging for a single-cylinder engine, focusing on fill time, optimal volume, density gain, and thermal effects due to adiabatic compression of the intake air.

Liquefied Petroleum Gas direct injection (LPG DI) is believed to be the key enabler for the adaption of modern downsized gasoline engines to the usage of LPG, since LPG DI avoids the significant low end torque drop, which goes along with the application of conventional LPG port fuel injection systems to downsized gasoline DI engines, and provides higher combustion efficiencies. However, especially the high vapor pressure of C3 hydrocarbons can result in hot fuel handling issues as evaporation or even in reaching the supercritical state of LPG upstream or inside the high pressure pump (HPP). This is particularly critical under hot soak conditions. As a result of a rapid fuel density drop close to the supercritical point, the HPP is not able to keep the rail pressure constant and the engine stalls.

This paper presents the results of an experimental investigation on a single cylinder engine to validate a two-component JP-8 surrogate. The two-component surrogate was chosen based on a previous investigation where the key properties, such as DCN, volatility, density, and lower heating value, of the surrogate were matched with those of the target JP-8. The matching of the auto-ignition, combustion, and emission characteristics of the surrogate with JP-8 was investigated in an actual diesel engine environment. The engine tests for the validation of the surrogate were conducted at an engine speed of 1500 rpm, a load of 3 bar, and different injection timings. The results for the cylinder gas pressure, ignition delay period, rate of heat release, and the CO, HC, and NOx emissions showed a good match between the surrogate and the target JP-8. However, the engine-out particulate matter for the surrogate was lower than that for the JP-8 at all tested conditions.

Abstract Two new misfire detection indexes for single-cylinder motorcycle engines—dubbed gap distance (GD) and gap slope (GS)—are proposed in this study. GD and GS quantify the change in engine angular acceleration using the tooth time measured by the crankshaft position sensor (CKPS). GD is defined as the product of the spacing distance I (the distance from the top dead center at the explosion stroke [TDC2] to the engine speed trend line parallel to the engine speed axis) and spacing distance II (the distance from the bottom dead center at the expansion stroke [BDC2] to the engine speed trend line parallel to the engine speed axis). GS is defined as the difference between the two slopes between the engine speed inclination line and the engine speed trend line. Here the engine speed trend line connects two engine speeds at the top dead center at the intake stroke (TDC1) of the current and subsequent cycles.

This SAE Recommended Practice establishes uniform laboratory techniques for the continuous and grab sample measurement of various constituents in the exhaust gas of the gasoline engines installed in passenger cars and light trucks. The report concentrates on the measurement of the following components in exhaust gas: hydrocarbons (HC), carbon monoxide (CO), carbon dioxide (CO2), nitric oxide (NO), nitrogen dioxide (NO2), and oxygen (O2). This recommended practice includes the following sections: 1. Introduction 2. Definitions and Terminology 3. Sampling and Instrumentation 4. Associated Test Equipment 5. Test Procedures Appendix—Other Measurement Technology

In the framework of an increasing demand for a more sustainable mobility, where the fuel consumption reduction is a key driver for the development of innovative internal combustion engines, Turbulent Jet Ignition (TJI) represents one of the most promising solutions to improve the thermal efficiency. However, details concerning turbulent jet assisted combustion are still to be fully captured, and therefore the design and the calibration of efficient TJI systems require the support of reliable simulation tools that can provide additional information not accessible through experiments. To this aim, an experimental investigation combined with a 3D-CFD study was performed to analyze the TJI combustion characteristics in a single-cylinder spark-ignition (SI) engine. Firstly, the model was validated against experiments considering stoichiometric mixture at 3000 rpm, wide open throttle operating conditions.

This SAE Information Report lists engine and laboratory tests for service fill engine oils which are associated with specifications and classifications established outside of North America. These specifications and classifications include those developed prior to June 1, 2000, by International Technical Societies as well as individual original equipment manufacturers. The information contained within this report applies to engine oils utilized in gasoline and diesel powered automotive vehicles.