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An electronic controlled rapid burning system with a high energy, dual-spark plug ignition system in a high speed LPG engine with a sole LPG-fueled port fuel injection (PFI) system for the steady state lean operation is discussed in this paper. A Multi-channel SI engine Combustion Process Analysis System was developed in this research. The synchronizing and asynchronous ignition timing can be realized by ECU and the control strategies according to the engine operation conditions. Test results showed that the lean mixture flame propagation was improved by the enhanced ignition energy intensity in this system. To cooperate with the combustion chamber and the spark location, the flame propagation distance was shortened for rapid burning.

As the key components of internal combustion engine(ICE), the crankshaft main bearings are used to support the crankshaft and connecting rod mechanism whose rotary motion realizes the energy conversion from heat energy to mechanical power in cylinder. The lubrication performances and wear life of crankshaft main bearings directly affect ICE working efficiency and reliability. Therefore, it is very important to study the lubrication performances of crankshaft main bearings. In this paper, a 16V marine diesel engine was studied. Based on the AVL-Designer software platform, a dynamic model of crankshaft and connecting rod mechanism and a hydrodynamic lubrication model of crankshaft main bearing were built. The numerical analyses were carried out on the lubrication performances of crankshaft main bearings under different speed conditions.

In recent years, more attentions have been paid to stringent legislations on fuel consumption and emissions. Turbocharged downsized gasoline direct injection (DI) engines are playing an increasing important role in OEM’s powertrain strategies and engine product portfolio. Dongfeng Motor (DFM) has developed a new 1.0 liter 3-cylinder Turbocharged gasoline DI (TGDI) engine (hereinafter referred to as C10TD) to meet the requirements of China 4th stage fuel consumption regulations and the China 6 emission standards. In this paper, the concept of the C10TD engine is explained to meet the powerful performance (torque 190Nm/1500-4500rpm and power 95kW/5500rpm), excellent part-load BSFC and NVH targets to ensure the drivers could enjoy the powerful output in quiet and comfortable environment without concerns about the fuel cost and pollution.

With a tighter regulatory environment, reduction of hydrocarbon emissions has emerged as a major concern for advanced low-temperature combustion engines. Currently precious metal-based diesel oxidation catalysts (DOC) containing platinum (Pt) and palladium (Pd) are most commonly used for diesel exhaust hydrocarbon oxidation. The efficiency of hydrocarbon oxidation is greatly enhanced by employing both Pt and Pd together compared to the case with Pt or Pd alone. However, there have been few systematic studies to investigate the effects of the ratio of platinum to palladium on catalytic oxidation over the DOC. The present study illustrates the relationship between the Pt-Pd ratio and catalyst activity and stability by evaluating a series of catalysts with various Pt to Pd ratios (1:0, 7:1, 2:1, 1:2, 1:5, 0:1). These catalysts were tested for their CO and hydrocarbon light-off temperatures under simulated conditions where both unburned and partially burned hydrocarbons were present.

The cold starting and cold-state running cycle (i.e. engine warming up) of gasoline engines are the key points of exhaust emissions formation of modern engines, and also one of the very important targets for the increasingly stringent emissions regulations. The combustion stability in gasoline engine cold starting and warming up will impact the formation of its exhaust emissions. This paper introduces the improvement in cold starting and warming up combustion process for the motorcycle gasoline engine by high-energy, dual-spark plug based rapid burning system. Test results showed that the high-energy, dual-spark plug based rapid burning system was very helpful to rapid ignition under the engine cold starting condition. Meanwhile, because of increasing the burning velocity of the engine mixture, this solution can realize the larger ignition retard and stable combustion process under the engine warming-up condition.

Exhaust Gas Recirculation (EGR) is an extensively applied approach for the engine emission control, which is the most effective for reducing NOX emissions. However, as increasing EGR rate, the burning velocity of LPG mixture will be slow that it impacts the complete combustion and combustion stability. The effects of EGR on the rapid lean-burning and NOX emissions of the LPG engine with EFI is introduced in this paper. Test data showed that the dual-spark plug ignition-based rapid burning system could increase the combustion rate of LPG mixture, and improve the rapid burning process of the LPG engine with EGR. Meanwhile, the excess air rate Φa limits of LPG lean-burning will be largely extended within the whole effective range of EGR rate. At the equivalent running conditions of LPG engine, largely extended EGR rate could restrain the formation of NOX emissions by the high combustion temperature.