Gasoline Passenger Cars Research Articles

An experiment of lubricating oil gas concentration in the standardized driving cycles

There always is cavitation in the positive displacement pump, and the bubbles in the lubricating oil have a great influence on the lubricating performance. This paper aims to measure the lubricating oil gas concentration of a passenger car gasoline engine in the standardized driving cycles. We use a passenger car engine lubricating system in the lubricating experiment, simulating the lubricating oil pump working state in the standardized driving cycles. The lubricating oil density and flow rate are measured to calculate the gas concentration in the lubricating oil, according to the engine work state in the standardized driving cycles, including NEDC Urban, NEDC Ultra Urban, WLTC High Speed. The test results show that under the steady-state conditions, the gas volume ratio decreases linearly with the increase of the outlet pressure, the air mass ratio increases with the increase of the pump speed. In the driving cycles, the air mass ratio also increases with the increase of outlet pressure, and it has a high positive correlation with lubricating oil flow and pump speed. With the increase of oil temperature from 25 to 100°C, the air volume ratio decreases by 72.6%, and the air mass ratio decreases by 84.3%. In the engine accelerating state, the rate of lubricating oil flow gain lags behind the pump speed, which makes the lubricating oil gas mass ratio in the accelerating state is significantly higher than that in the decelerating state.

Estimation of Cold Roll Forming Characteristics of Wrought Magnesium Alloy with Tension-Compression Asymmetry

In recent years, the movement for banning the sale of gasoline cars and diesel vehicles, especially in Europe, and allowing only electric passenger cars has been accelerated. For examples, Germany’s federal council, the Bundesrat, has passed a resolution calling for a ban on combustion engine cars by 2030. If the ban were to go through, German citizens would only be permitted to purchase electric or hydrogen-fueled cars. In Norway, until 2025 there is a movement for legislation prohibiting the registration of new gasoline passenger cars and diesel cars. Beginning in 2025 in the Netherlands, a bill prohibiting the sale of new cars gasoline and diesel vehicles was submitted to Congress. Under the circumstances, the demand for light-weight products for automotive industries has increased due to global trends in environmental preservation. Although demands for magnesium has risen dramatically, production of magnesium alloy sheet still remains at a very low level. This study seeks to establish a guideline for roll design in the roll forming of wrought magnesium alloys to extend practical use of roll-formed products of wrought magnesium alloys. A three-dimensional elasto-plastic analysis by the finite-element method has been conducted to express exact roll-forming behavior of wrought magnesium alloys that have different stress-strain curves in tension and compression. Simple V-sections were formed by a tandem six-stand roll forming machine to demonstrate the effectiveness of the simulation methods with different stress-strain curves in the case of tension and compression. Also, spring-back analysis has been performed to investigate the exact cold roll-forming phenomenon for wrought magnesium alloy sheets.

In situ multimodal imaging for nanoscale visualization of tribofilm formation

A third of the energy from fuel combustion in passenger car gasoline engines is lost due to friction. Carefully designed engine lubricants can recover some of these losses by reducing friction and wear by forming a nanometer-scale chemico-physico tribofilm between surfaces. Accordingly, attention has focused on developing oil formulations that form low-friction tribofilms. However, analyses of resultant tribofilms are typically conducted after tribo-tests with conventional characterization tools and do not offer insights into tribofilm formation and evolution, precluding information critical to tuning tribofilm properties. In this work, we developed a unique multimodal methodology based on Atomic Force Microscopy (AFM) with local probe heating for in situ tribological studies that activates friction modifiers and simultaneously captures the evolution of friction and surface roughness, with nanometer resolution. As a platform to demonstrate the ability of this methodology to visualize dynamics of tribofilm formation in situ, we apply it to molybdenum-based friction modifiers to distinguish key factors in their functionality and correlate nanoscale AFM and Friction Force Microscopy data to bench tribo-tests used in the industry. To decode the formation mechanisms observed in situ and underlying chemistry of tribofilms, we performed ab initio Molecular Dynamics (AIMD) simulations at comparable conditions. AIMD simulations confirmed both nanoscale and bench tribo-test results and showed deviations in molecular organization in tribofilms that are formed from different molybdenum-based friction modifiers that corroborates with surface functionality. With this innovative methodology, we demonstrate proof-of-principle in situ formation of molybdenum-based tribofilms directly on steel surfaces that could be applied generally to studying tribofilm formation.

Regulated and Non-Regulated Emissions from Euro 6 Diesel, Gasoline and CNG Vehicles under Real-World Driving Conditions

The transport sector is one of the main sources air pollutants. Different exhaust after-treatment systems have been implemented over the years to control the emissions of criteria pollutants. However, while reducing the emissions of the target compounds these systems can lead to the emissions of other pollutants and/or greenhouse gases such as NH3 or N2O. Following the implementation of the Real Driving Emissions (RDE) test procedure in the EU, vehicles have been equipped with more complex after-treatment configurations. The impact that these technologies may have on the emissions of non-regulated pollutants during real-world driving have not been evaluated until now. In the current study we present the on-road emissions of a series of non-regulated pollutants, including NH3, N2O, CH4 and HCHO, measured with a portable FTIR from a series of Euro 6d, Euro 6c and Euro 6d-TEMP, gasoline diesel and compressed natural gas (CNG) vehicles during real-world testing. The obtained results show that it is possible to measure N2O, NH3, CH4 and HCHO during on-road operation. The results also highlight the importance of the measurement of the emissions of these pollutants during real-world driving, as the emissions of NH3 (a particulate matter precursor) and those of N2O and CH4 (green-house gases) can be high from some vehicle technologies. NH3 emissions were up to 49 mg/km for gasoline passenger cars, up to 69 mg/km for the CNG light-commercial vehicle and up to 17 mg/km a diesel passenger car equipped with a selective catalytic reduction system (SCR). On the other hand, N2O and CH4 emissions accounted for up to 9.8 g CO2 eqv/km for a diesel passenger car equipped with a combination of diesel oxidation catalysts (DOC), lean NOx traps (LNT), SCR and possibly an ammonia slip catalyst ASC.

Numerical Investigation of 48 V Electrification Potential in Terms of Fuel Economy and Vehicle Performance for a Lambda-1 Gasoline Passenger Car

Real Driving Emissions (RDE) regulations require the adoption of stoichiometric operation across the entire engine map for downsized turbocharged gasoline engines, which have been so far generally exploiting spark timing retard and mixture enrichment for knock mitigation. However, stoichiometric operation has a detrimental effect on engine and vehicle performances if no countermeasures are taken, such as alternative approaches for knock mitigation, as the exploitation of Miller cycle and/or powertrain electrification to improve vehicle acceleration performance. This research activity aims, therefore, to assess the potential of 48 V electrification and of the adoption of Miller cycle for a downsized and stoichiometric turbocharged gasoline engine. An integrated vehicle and powertrain model was developed for a reference passenger car, equipped with a EU5 gasoline turbocharged engine. Afterwards, two different 48 V electrified powertrain concepts, one featuring a Belt Starter Generator (BSG) mild-hybrid architecture, the other featuring, in addition to the BSG, a Miller cycle engine combined with an e-supercharger were developed and investigated. Vehicle performances were evaluated both in terms of elasticity maneuvers and of CO2 emissions for type approval and RDE driving cycles. Numerical simulations highlighted potential improvements up to 16% CO2 reduction on RDE driving cycle of a 48 V electrified vehicle featuring a high efficiency powertrain with respect to a EU5 engine and more than 10% of transient performance improvement.

Cold Roll Forming Behavior of Wrought Magnesium Alloy with Tension - Compression Asymmetry

In recent years, the movement that banning the sale of gasoline cars and diesel vehiclesespecially in Europe and allowing only electric cars for passenger’s cars has been accelerated. Forexamples, Germany’s federal council, the Bundesrat, has passed a resolution calling for a ban oncombustion engine cars by 2030. If the ban were to go through, German citizens would only bepermitted to purchase electric or hydrogen-fueled cars. In Norway, until 2025 there is a movement tolegislation prohibiting the registration of new cars for passenger car gasoline and diesel cars.Beginning in 2025 in the Netherlands, a bill to prohibit the sale of new cars for gasoline and dieselvehicles was submitted to Congress. Under the circumstances, the growing demand for light weightproducts for automotive industries has been increased due to global trend of environmentalpreservation. Although requires of magnesium has risen dramatically, production of magnesium alloysheet remains still at a very low level in practical use. The aim of the study is to establish a guidelinefor roll design in the roll forming of wrought magnesium alloys to extend practical use of roll formedproducts of wrought magnesium alloys. A three-dimensional elasto-plastic analysis by finite elementmethod has been conducted to express exact roll forming behavior of wrought magnesium alloys thathave different stress-strain curves in tension and compression. A simple V-sections were formed by atandem six stands roll forming machine to demonstrate effectiveness of the simulation methods withdifferent stress-strain curves in the case of tension and compression. Also, spring back analysis hasbeen performed to investigate exact cold roll forming phenomenon for wrought magnesium alloysheets.

Real driving emissions of a scooter and a passenger car in Naples city

The aim of the study was to investigate the real driving emissions of two vehicles widely used as private means of transport in Italian cities: a Euro 4 gasoline passenger car and a Euro 3 scooter. Exhaust emissions of two and four wheel vehicles were characterised over three urban routes in Naples. On-board measurement of CO, NOx, CO2 and fuel consumption of the car was made with a Portable Emissions Measurement System (PEMS); exhaust emissions of NOx and fuel consumption of the scooter were measured in the laboratory, reproducing speed profiles acquired on the road on a chassis-dynamometer. In both cases, vehicle spatial position was acquired by Global Positioning System (GPS) at a frequency of 10 Hz. Real vehicle speed and acceleration together with road gradient were used to evaluate the specific power of the vehicle (VSP) and the results were modelled so as to correlate emissions with driving activities. Specific emissions and fuel consumption were also analysed as a function of road gradient. The most critical results for the car concerned NOx emissions which greatly exceeded the type-approval limit, and real driving of the scooter involved a significant increase in fuel consumption. For both vehicles, positive road gradient greatly influenced fuel demand, while NOx and CO emissions were considerably reduced on downhill stretches.

Carbon Emissions and Expressway Traffic Flow Patterns in China

Traffic flow patterns severely impact vehicle carbon emissions. A field test was conducted in this study to obtain fuel consumption and traffic volume data under various traffic flow patterns and to explore the relationship between traffic flow patterns and vehicle carbon emissions. Carbon emission data were obtained via the indirect carbon emission accounting method proposed by the Intergovernmental Panel on Climate Change. Carbon emission prediction models for diesel trucks and gasoline passenger cars were established respectively with volume to capacity ratio as an explanatory variable. The results show that carbon emissions are highest under the congested flow conditions, followed by unstable flow, free flow, and steady flow. The relationship between the volume to capacity ratio and carbon emissions is a cubic curve function. The carbon emissions of trucks and passenger cars with a volume to capacity ratio of 0.4 to 0.5 are relatively small. The proposed carbon emissions models effectively quantify the carbon emissions of vehicles under different traffic flow patterns. The results of this study may provide data to support and a workable reference for expressway operation management and future low-carbon expressway expansion construction projects.

On the improvement by laser ignition of the performances of a passenger car gasoline engine.

Laser ignition was used to operate a four-stroke, four-cylinder, multipoint fuel injection gasoline passenger car engine, replacing the engine classical ignition device. The laser ignition system was compactly built with diode end-pumped Nd:YAG/Cr4+:YAG composite ceramics, each laser spark plug delivering pulses at 1.06 μm with 4 mJ energy and 0.8ns duration at variable repetition rate, in accordance with the engine speed. The engine was operated at constant speed-constant load condition of 2000 rpm-2 bar equivalent brake mean effective pressure, and different ignition timings, thus simulating city traffic situations. Two relative air-fuel ratios have been considered: λ~1 for the stoichiometric mixture operation and λ~1.25 for the lean mixture condition. Parameters indicating engine performance, efficiency, combustion stability, and emissions have been measured and registered when groups of 500 consecutive cycles were acquired. The engine brake power, brake specific fuel consumption, coefficient of variability for indicated mean effective pressure, initial and main combustion stage durations, as well as exhaust emissions like carbon monoxide (CO) and total unburned hydrocarbons (THC) emphasized that significant improvements can be obtained for lean air-fuel mixture operation. Increases of the nitrogen oxides emission (NOx) were measured when laser ignition was used.

On the Effect of Addition of 1,2-Propylene Glycol Composition on Power and Torque of an EFI Passenger Car Fueled with Methanol-Gasoline M15

The utilization and development of clean and renewable energy resources is very attractive because of the world sustainability and environmental pollution. Methanol, ethanol and their blends with gasoline are well known as important alternative fuels for vehicle engines. A serious problem encountered in using gasoline–alcohol blends as motor fuel at low temperatures is the separation of the mixture into two liquid phases, which is strongly influenced by the water content. An important multi-purpose chemical that has an extensive use as anti-freeze agent, 1,2-propylene glycol, is attracting interest in recent years as an additive for methanol-gasoline fuel. The aim of this work is to investigate the effect of composition of the 1,2-propylene glycol additive on engine power and torque of an EFI passenger car fueled with methanol-gasoline blend M15. Research was conducted in the laboratory on a 1.2 L small gasoline passenger car, equipped with electronic injection system, using a blend of 15% gasoline and 85% methanol, by varying the composition of additive of 3 ml/l, 4 ml/l, 5 ml/l, 6 ml/l, 7 ml/l, 8 ml/l, 9 ml/l, and 10 ml/l. The measurement of power and torque was facilitated by using a simple engine dyno scanner on a dynamometer roll chassis. From the study it has found that the effect of variation of additive composition tend to decrease engine power, but the value of the torque has a little bit increased, compared to pure gasoline engine. There was a best value of additive composition that showed high power and torque. According to the effect of additive composition on the power and torque it can be concluded that the best additive composition is 8 ml/l, which is 86.6 Nm on 2500 rpm, while the power remains constant in the value of 51.7 kW on 5800 rpm..

Experimental investigation of a variable compression ratio system applied to a gasoline passenger car engine

Gasoline spark-ignited internal combustion engines for passenger cars are still a major part of the worldwide market share. With legislation pushing towards a lower carbon footprint, many technological alternatives are under scrutiny. Among them, one of the most promising is a variable compression ratio (VCR). This paper aims to experimentally prove the potential of this technology when applied to a state-of-the-art 3-cylinder, direct injection, turbocharged engine fuelled with regular RON 95 gasoline. A 2-stage variable compression ratio (VCR) system was applied to a series engine: The VCR prototype engine features compression ratio stages of 9.56:1 and 12.11:1. The engine has undergone only minor modifications, remaining substantially original. Dynamometer tests with in-cylinder pressure analysis were performed. The engine was tested over an operational map up to 4000 rpm and up to 26 bar BMEP, with stoichiometric operation and original ECU calibration. A fuel consumption reduction of up to 4% was found at part-load, where combustion phasing tended to be optimum. Penalties in fuel consumption at high loads were present due to knock-limited spark-timing. Results show that an even higher compression ratio variation range would further reduce of fuel consumption in both low and high load.

Study of the Incentive Caused by the Scrappage Program in Accelerating Old-Car Replacement in Order to Reduce Gas Emissions from Gasoline Passenger Cars in Indonesia

This paper describes a scenario designed to reduce the emission level of non-euro cars that makes up more than 80% of the current car stock in 2013, even though the number of non-euro cars is only a maximum of 24% of the total population. We have applied an incentive for people to replace their non-euro car with a newer LCGC car through a scrappage program. Willingness to change was determined through a questionnaire to determine the respondent’s willingness to change to an LCGC car. From the survey, the financial aspect still dominated the motivation behind the replacement. This was shown from the choice of the highest incentive fee of $2,000 USD per unit. By applying 78% and 82% to describe the probability of changing to the LCGC car and the incentive option of $2,000 USD respectively, it was proven that the incentive program can reduce the population of non-euro cars. From the results, it can be seen that emission gases CO, NO, and HC decreased significantly; CO by 59.3%, NO by 68.1%, and HC by 35.4% compared to without the scrappage incentive program by 2030. Because each unit is replaced with a LCGC car, the population balance is zero. The increase of the emission level from the additional number of LCGC cars is not significant compared to the emissions from non-euro cars. We conclude that the incentive program for non-euro cars is one of the most effective ways to reduce the gas emission level.

Piston system for friction reduction in modern gasoline passenger car engines

Piston system for friction reduction in modern gasoline passenger car engines

Characterization and carcinogenic risk assessment of polycyclic aromatic and nitro-polycyclic aromatic hydrocarbons in exhaust emission from gasoline passenger cars using on-road measurements in Beijing, China

The polycyclic aromatic hydrocarbon (PAH) and nitro-polycyclic aromatic hydrocarbon (NPAH) emissions from 16 gasoline passenger cars, encompassing five emission standards and two driving conditions, were tested using a portable emission measurement system (PEMS) in Beijing under on-road conditions. In total, 16 PAHs and 9 NPAHs were quantified in both the gaseous and particulate phases by high-performance liquid chromatography (HPLC). The results indicated that lower PAH and NPAH emissions were observed with improved emission standards, especially for China 3 to China 5 vehicles (P < 0.05). Higher emission factors (EFs) were detected on nonhighway roads than on highway roads due to incomplete combustion. Although most PAHs and NPAHs were in the gas-phase, the TEQBaP of the particulate-phase PAHs was 4.2 times higher than that of the gas-phase PAHs, whereas the opposite pattern was observed for NPAHs. The TEQBaP EFs on nonhighway roads were 1.0–2.3 times higher than those on highway roads. The results of this study will be valuable for estimating the emissions and performing carcinogenic risk assessment of PAHs and NPAHs from urban gasoline passenger cars on roads. Formulating more stringent regulations and emission control technologies for PAHs and NPAHs is important.

Life cycle assessment of wheat straw lignocellulosic bio-ethanol fuel in a local biorefinery prospective

Abstract A ″cradle-to-wheel life cycle analysis was carried out to investigate the environmental profile of bioethanol (EtOH) production from lignocellulosic wheat straw (WS) and its use as transport fuel in E10 (10% of EtOH and 90% of gasoline) and E85 (85% of EtOH and 15% of gasoline) vehicles. The aims of this study were: (i) to evaluate the environmental performance of the whole WS-EtOH supply chain and (ii) to identify the best performing feedstock for a prospective bio-refinery network in Campania Region (Southern Italy). A comparison of WS-EtOH system against the fossil counterpart (gasoline passenger car) and similar bio-based production-use chains was conducted to fulfil one of the main goals of EnerBiochem and BioPoliS projects: investigating the environmental profitability of a bio-refinery system in Campania Region. Starting from the use of residual feedstock (wheat straw) or the revaluation of marginal lands (cultivation of dedicated perennial giant reed or annul fiber sorghum), through the investigation of an advanced lignocellulosic conversion processes, this work assesses the environmental feasibility of bio-energy production in Campania Region. The WS-E10 environmental profile was driven by the gasoline input in the blend, whilst the WS-E85 results showed the relevance of the crop phase. The comparison of the different blends and the gasoline-fuelled car highlighted for E10-blends similar profiles for almost all the impact categories, nearly overlapping with the conventional vehicle. Differently, for E85 vehicles, the differences between the bio-based systems appeared amplified according to the specific impacts of the feedstock supply and the conversion steps. On the whole, Fiber Sorghum-E85 system showed the worst environmental profile whilst WS-E85 entailed the best performance.

Experimental analysis of the V-Charge variable drive supercharger system on a 1.0 L GTDI engine

A compound charging system that pairs a turbocharger with a supercharger seems to be a potential trend for future passenger car gasoline engines, as the strength of both could be enhanced and the deficiencies of each could be offset. The use of a fixed-ratio positive-displacement supercharger system on a downsized turbocharged gasoline engine has already appeared on the market. Although such systems can achieve enhanced low-end torque and improved transient response, several challenges still exist. An alternative solution to the fixed-ratio positive-displacement supercharger is the V-Charge variable ratio centrifugal supercharger. This technology utilizes a Torotrak continuously variable transmission (CVT) coupled to a centrifugal compressor for near silent boosting. With a wide ratio spread of 10:1 and rapid rate of ratio change, the compressor speed can be set independently of the engine speed to provide an exact boost pressure for the required operating points, without the need to recirculate the air through a bypass valve. A clutch and an active bypass valve can also be eliminated, due to the CVT capability to down-speed, thus improving the noise vibration and harshness performance. This paper will, for the first time, present and discuss the V-Charge technology optimization and experimental validation on a 1.0 L GTDI engine to achieve a better brake specific fuel consumption and transient response over the turbo-only and the fixed-ratio positive-displacement supercharger solution. The potential for the V-Charge system to increase the low-end torque and enable a down-speeding strategy is also discussed.

Experimental testing and simulations of speed variations impact on fuel consumption of conventional gasoline passenger cars

Speed variations are considered as an alternative for reducing fuel consumption during the use phase of passenger cars. It explores vehicle engine operating zones with lower fuel consumption, thus making possible a reduction in fuel consumption when compared to constant speed operation. In this paper, we present an evaluation of two conditions of speed variations: 50–70 km/h and 90–110 km/h using numerical simulations and controlled tests. The controlled tests performed on a test track by a professional pilot show that a reduction in fuel consumption is achievable with a conventional gasoline passenger car, with no adaptations for realizing speed variations. Numerical simulations based on a backward quasi-static powertrain model are used to evaluate the potential of speed variations for reducing fuel consumption in other speed variation conditions. When deceleration is performed with gear in neutral position, simulations show that speed variations are always correlated to a lower fuel consumption. This was suspected through previous numerical tests or evaluation on test bench but not in controlled tests conditions.

Registro de información en motores de automóviles y desarrollo de un ciclo de conducción piloto para la ciudad de Pereira usando herramientas de diagnóstico de bajo costo

El objetivo de este trabajo es presentar una metodología para la obtención de un ciclo de conducción representativo del tráfico en la ciudad de Pereira, Colombia, usando herramientas de bajo costo. Se escogieron cuatro vehículos equipados con sistemas de registro de velocidad y aceleración para circular en uno de los corredores viales más congestionados de la ciudad. Las características de velocidad y aceleración fueron analizadas y se evaluaron y definieron los parámetros de conducción. Se diseñó un método para construir el ciclo de conducción y se construyó el ciclo. Como resultado, se obtuvo un ciclo simple de conducción que puede servir de referencia para el análisis de consumo de combustible y diseño de estrategias para control de emisiones de automóviles bajo las condiciones de operación en la zona urbana de Pereira. En el ámbito del mismo proyecto, también se estudió la utilidad de la información recolectada, con herramientas de diagnóstico de bajo costo, durante la operación de los vehículos para propósitos de evaluación del desempeño de los motores.

The impact of running-in on the friction of an automotive gasoline engine and in particular on its piston assembly and valve train

Generally, mating surfaces that are in tribological contact undergo a running-in process at the beginning of their operational lifetime. During this running-in phase, the tribological operating condition changes significantly leading ideally to long-term operation with a minimum of continuous wear. While this process and its duration are rather well understood for single machine elements like journal bearings, it is the aim of this work to investigate the running-in behaviour of more complex systems like an internal combustion engine and its sub-assemblies. To gain insight into the influence and duration of this running-in phase, a series of tests have been performed under realistic engine operating conditions. To be able to separate the running-in processes for the individual subsystems’ piston assembly, valve train and journal bearings of the crank train, a large series of tests have been conducted for a conventional gasoline passenger car engine. The results show a strong influence of the running-in process on total engine friction, which can be attributed mostly to the direct acting valve train and to a considerably lesser extent to the piston assembly.

Erratum to: Biological Effects in Lung Cells In Vitro of Exhaust Aerosols from a Gasoline Passenger Car With and Without Particle Filter

Erratum to: Biological Effects in Lung Cells In Vitro of Exhaust Aerosols from a Gasoline Passenger Car With and Without Particle Filter