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1.
This paper reviews the particle emissions formed during the combustion process in spark ignition and diesel engine. Proposed
legislation in Europe and California will impose a particle number requirement for GDI (gasoline direct injection) vehicles
and will introduce the Euro 6 and LEV-III emission standards. More careful optimization for reducing particulate emission
on engine hardware, fuel system, and control strategy to reduce particulate emissions will be required during cold start and
warm-up phases. Because The diesel combustion inherently produces significant amounts of PM as a result of incomplete combustion
around individual fuel droplets in the combustion zone, much attention has been paid to reducing particle emissions through
electronic engine control, high pressure injection systems, combustion chamber design, and exhaust after-treatment technologies.
In this paper, recent research and development trends to reduce the particle emissions from internal combustion engines are
summarized, with a focus on PMP activity in EU, CARB and SAE papers and including both state-of-the-art light-duty vehicles
and heavy-duty engines. 相似文献
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This paper presents a review of the characterization of physical properties, morphology, and nanostructure of particulate emissions from internal combustion engines. Because of their convenience and readiness of measurement, various on-line commercial instruments have been used to measure the mass, number, and size distribution of nano-particles from different engines. However, these on-line commercial instruments have inherent limitations in detailed analysis of chemical and physical properties, morphology, and nanostructure of engine soot agglomerates, information that is necessary to understand the soot formation process in engine combustion, soot particle behavior in after-treatment systems, and health impacts of the nano-particles. For these reasons, several measurement techniques used in the carbon research field, i.e., highresolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and Raman spectroscopy, were used for analysis of engine particulate matter (PM). This review covers a brief introduction of several measurement techniques and previous results from engine nano-particle characterization studies using those techniques. 相似文献
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This paper is review of the characterization of exhaust particles from state-of-the-art internal combustion engines. We primarily focus on identifying the physical and chemical properties of nano-particles, i.e., the concentration, size distribution, and particulate matter (PM) morphology. Stringent emissions regulations of the Euro 6 and the LEV III require a substantial reduction in the PM emissions from vehicles, and improvements in human health effects. Advances in powertrains with sophisticated engine control strategies and engine after-treatment technologies have significantly improved PM emission levels, motivating the development of new particle measurement instruments and chemical analysis procedures. In this paper, recent research trends are reviewed for physical and chemical PM characterization methods for gasoline and diesel fueled engines under various vehicle certification cycles and real-world driving conditions. The effects of engine technologies, fuels, and engine lubricant oils on exhaust PM morphology and compositions are also discussed. 相似文献
5.
A. Pesiridis 《International Journal of Automotive Technology》2012,13(6):873-884
The application of active control means to regulate the flow of exhaust gas in a turbocharger turbine is a concept developed by the Turbomachinery Group at Imperial College, London. It is a new concept the first results of which were made public in 2004. This paper presents the theoretical grounding behind the idea, its development and the elements required for a successful implementation of active control for a turbocharger turbine and the integration of such a turbocharger system within an internal combustion engine. This paper is intended to fill a gap in the theoretical understanding of the issues pertaining to the concept of Active Control for Turbocharger Turbines. The discussion is led towards a theory summarising the flow physics and their effect on the behaviour of the exhaust gas flow occurring during turbocharger turbine inlet geometrical changes and the implications from the periodic nature of these geometric changes in particular with respect to cycle performance results both for the turbocharger and for the engine. This paper is written with the purpose of presenting a realistic context of ACT operation by identifying and considering those parameters relevant to the operation and successful application of ACT to an internal combustion engine. In addition, the requirements for a dedicated ACT control strategy which can be effective in the ACT-engine integrated environment are, also, highlighted. 相似文献
6.
《JSAE Review》1994,15(2):101-107
In the present study a new test method is investigated to measure the total friction loss of engines over the whole range of speed and load. It is based on the idea that the friction loss close to the true one of fired and braked engines can be measured by the run-out method because the temperature mainly influencing the friction loss is almost stable for the short run-out test duration. From the test results and the comparison with those measured by other conventional test methods, the following becomes evident:
- 1.(1) The total friction mean effective pressure slightly increases as the revolution speed becomes high, but it decreases as either the load or the cooling water temperature becomes high.
- 2.(2) The total friction mean effective pressure measured by the present method is smaller than that measured by the run-out method, the motoring method or Willans-line method, but it is larger than that measured by the indicated pressure diagram method.
7.
分析了内燃机电站在可靠性设计方法中存在的一些问题,并提出了改进建议,强调了故障特性分析对可靠性设计的重要性及采用任务可靠性设计方法的实际意义。 相似文献
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《JSAE Review》1995,16(1):27-33
The influence of fuel properties on combustion characteristics and exhaust emissions in a direct injection stratified charge SI engine with a “two-stage fuel injection system” was examined. The results showed that this type of DISC combustion system can be used with a wider range of fuels than ordinary homogeneous combustion systems. Lower exhaust emissions and higher thermal efficiency were achieved even with fuels with lower octane numbers and higher distillation temperatures. 相似文献
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J. Lucas M. A. Houghton I. G. Masheter 《International Journal of Automotive Technology》2012,13(6):853-860
A system has been researched over the past 3 years for reducing the exhaust pollutants from diesel engines for light commercial vehicles. The system researched achieves Euro 6 standards for reduction of polluting gases (CO, HC, PM, NO). It consists of 4 main sections: 1. A heater and heat exchanger (HE); 2. A CO/HC oxidising catalyst (D°C); 3. Pt catalyst on a diesel particulate filter (DPF); 4. A NO reducing reaction (SCR) within the DPF. The system operates as follows. The exhaust gas contains oxidising gases, namely both O2 and NO2. The levels of CO and HC are oxidised by O2 to CO2 for temperatures above 200°C. Carbon (PM) is oxidised to CO2 by NO2 but requires a temperature above 250°C. The operating exhaust temperature of 300°C is ideal for the removal of NO by using the Pt catalyst and the CO generated within the DPF. The heater is required to be able to raise the exhaust temperature at any time to 300°C in order to optimise the performance of the system, since diesel engine exhaust temperatures vary between 160°C (slow speeds) to 350°C (high speeds). Considerable heat is required (??3 kW) to maintain the exhaust gas for a 2l engine at 300°C for engine idle conditions. Therefore a heat exchanger is required to re-circulate the input heat and thereby reduce the maximum power consumption to a maximum of 500W over the engine full operating test cycle. This energy is supplied by the engine battery and alternator. Experimental results have been obtained for the exhaust from a Kubota diesel engine and the reductions in exhaust emissions of 83% (CO/ HC), 58% (NOx) and 99% (PM) were obtained. The PM was continuously cleaned so that there was no build up of back pressure. 相似文献
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《JSAE Review》1995,16(1):13-19
An investigation was made of the effects of intake valve closing timing on the spark-ignition engine combustion when the closing timing was varied for the purpose of reducing pumping loss. It was found that the principal cause of combustion deterioration was a drop in cylinder gas temperature and pressure, which was traced to a decline in the effective compression ratio and to a reduction in EGR gas and residual gas fraction. It was also observed that increasing the residual gas fraction worked to mitigate the deterioration of combustion. 相似文献
14.
B. H. Lee J. H. Song Y. J. Chang C. H. Jeon 《International Journal of Automotive Technology》2010,11(6):783-791
The diesel combustion process is highly dependent on fuel injection parameters, and understanding fuel spray development is
essential for proper control of the process. One of the critical factors for controlling the rate of mixing of fuel and air
is the number of injector holes in a diesel engine. This study was intended to explore the behavior of the formation of spray
mixtures, combustion, and emissions as a function of the number of injector hole changes; from this work, we propose an optimal
number of holes for superior emissions and engine performance in diesel engine applications. The results show that increasing
the number of holes significantly influences evaporation, atomization, and combustion. However, when the number of holes exceeds
a certain threshold, there is an adverse effect on combustion and emissions due to a lack of the air entrainment required
for the achievement of a stoichiometric mixture. 相似文献
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《JSAE Review》1998,19(4):319-327
This study aimed to reduce NOx and soot by creating a more homogeneous lean fuel distribution in a diesel spray using high-pressure fuel injection and a micro-hole nozzle. This injection system shortened the ignition delay, but a homogeneous lean fuel distribution in the diesel spray was not achieved. Using a lower cetane number fuel, the resulting longer ignition delay made a uniform, lean fuel distribution in the diesel spray possible with this injection system. Ignition and combustion were analyzed by the combustion chamber pressure history, and flame temperatures and KL values were analyzed by the two-color method. 相似文献
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《JSAE Review》1998,19(1):21-26
The effect of injection nozzle, diesel fuel density (volatility) and cetane number on diesel exhaust emissions were investigated. Decreasing injection nozzle hole diameter decreases PM emission. However, a small nozzle hole increases NOx emission and decreases the effect of fuel on PM emission. Decreasing fuel density is effective for reduction of NOx emission. But the effect is smaller than that of nozzle hole diameter and injection pressure. Furthermore injection timing retardation decreases the effect of fuel density on NOx emission. 相似文献
17.
This paper focuses on the mechanisms of combustion noise during the accelerating operation of multi-cylinder diesel engines
using testing technology for the transient conditions of IC engines. Based on impact factors, such as the gas dynamic load
and cylinder pressure oscillations, tests and analysis of the combustion noise during transient and steady-state conditions
for different loads are made on four-cylinder naturally aspirated engines, turbocharged engines, EGR-introduced engines, and
high pressure common rail engines. The laws of combustion noise difference for the same engine speed and load are researched
during transient and steady-state conditions. It is found that during transient conditions, the maximum pressure rise rate
and the high frequency oscillation amplitude of the cylinder pressure are all higher than those observed during steadystate
conditions for the same engine speed and load. With their joint action, the combustion noise during transient conditions is
greater than that during steady-state conditions. Turbocharging is useful in reducing the combustion noise during transient
conditions. Turbocharging has a better effect on the control over the combustion noise during transient conditions with a
constant engine speed and an increasing torque than in conditions with a constant torque and an increasing engine speed. One
of the main reasons for different control effects on the combustion noise is that turbocharging causes different wall temperatures
inside combustion chambers. The introduction of the appropriate EGR is helpful in the reduction of the combustion noise during
transient conditions. The key to the control of combustion noise with EGR during transient conditions is whether a real-time
adjustment to the EGR rate can be made to achieve the optimization of the EGR rates for different transient conditions. By
means of analyzing the differences in the combustion noise between the transient and steady-state conditions for different
pilot injection controls, we obtain a strategy for controlling the combustion noise during transient conditions with a pilot
injection. Compared with the steady-state conditions, a larger pilot injection quantity and a longer interval between the
main injection and pilot injection should be selected for transient conditions, and this is verified through tests. 相似文献
18.
Jinyoung Jang Youngjae Lee Ohseok Kwon 《International Journal of Automotive Technology》2017,18(5):751-758
This study was conducted to examine the impact of aged and new DPF systems of the Euro 5 diesel passenger car on fuel efficiency and exhaust emissions. Test diesel vehicle used in this study was equipped with diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) as aftertreatment systems, and satisfied the Euro-5 emissions standard. The displacement volume of engine was 1.6 L and the cumulative mileage was 167,068 km before the test. The FTP-75 test procedure was used, and the time resolved and weight based exhaust emissions of total hydrocarbon (THC), carbon monoxide (CO) and nitrogen oxides (NOx) were measured. The results show that the vehicle with the new DPF system has lower emissions of THC, CO and NOx than the aged one, and fuel efficiency also increased about 5 percent. The aged DPF system had higher backpressure due to the particulate matter (mostly in the form of ash) accumulated in the DPF. As was shown in the analysis using X-CT (X-ray computer tomography), the aged DPF system had particulate matter (PM) accumulated to a length of 46.6 mm. In addition, a component analysis of PM through XRF (X-ray fluorescence) analysis found that 50 % or more of the components consisted of the P, S, Ca, and Zn. 相似文献
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分析了柴油机的最大扭矩、扭矩储备系数、喷油系统喷油量与柱塞几何供油量的差异和变化规律,认为这3个参数的现行定义不够合理,给出了新的定义. 相似文献
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In this paper, the transient conditions during fast startup are investigated to develop a fuel metering strategy under HEV-like mode. The fuel mixture preparation and its effects on the combustion are analyzed in detail. Specifically, the combustion in the first cycle is characterized under both conventional low-speed cranking startup and HEV-like fast startup modes. The test results show that the enhancement of cranking speed has marginal effects on mixture preparation in the first cycle. However, it prolongs the combustion duration and reduces HC emissions. The sensitivity of the fuel metering is evaluated for the initial cycles. The combustion in the 3rd ~ 5th cycles during startup is found to be fairly sensitive to the fuel metering due to the effects of transient fuel film vaporization. The fuel metering in the first cycle has the most significant effect on the combustion and emissions during fast startup. Optimized fuel metering in the first cycle shows effective reduction of HC emissions during fast startup process. 相似文献