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381.
In this paper, the feasibility and advantages of employing high performance liquid chromatographic (HPLC) fingerprints combined with pattern recognition techniques for quality control of Shenmai inject...  相似文献   
382.
摘要通过分析和排除一起主机高压油管隐形泄漏的故障,阐述了MANB&W6S50MC柴油机高压油管安全保护装置的典型结构和工作原理,介绍了SOLAS公约对船舶柴油机高压油管安全保护方面的要求和技术标准。  相似文献   
383.
This paper proposes a rail pressure tracking controller based on a novel common rail system. A mathematical model, based on physical equations, is developed and used for feed forward control design. Rail pressure peak sampling mechanism is designed to remove the disturbance of rail pressure due to fuel injection. An enhanced tracking differentiator is designed to get smooth tracking signal and exact differential signal from signal with noise. Double loop control strategy is designed to decouple the system and to improve dynamic performance of the system. Experimental results indicate that fluctuation of rail pressure is within ±1 MPa in steady condition, while within ±3 MPa in transient condition, which verifies the effectiveness of the proposed rail pressure control strategy.  相似文献   
384.
IntroductionTo generate electricity from the fuel cell is bymeans of utilizing the electrochemistry reaction ofthe combustible gas ( H2 ,CH4etc.) in the fuel cellstack. The coal in solid state can't be directlyused. All the combined cycle generating systemcomposed of the coal as fuel and the fuel cell de-mands to realize the gasification of coal. This pa-per studied the possibility of utilization and devel-opment of the combined cycle generating systemthatis composed of the coal and the molt…  相似文献   
385.
桩端压力注浆桩主要是通过向桩底及桩端周围注入浆液,加固桩底及桩端周围的土体,形成一个具有高于原土层承载力的扩大头,从而提高桩的承载力。  相似文献   
386.
Compression ignition of homogeneous charges in internal combustion (IC) engines is expected to offer high efficiency of DI diesel engines without high levels of NOx and particulate emissions. This study is intended to find ways of extending the rich limit of HCCI operation, one of the problems yet to be overcome. Exhaust emissions characteristics are also explored through analyses of the combustion products. DME fuel, either mixed with air before induction or directly injected into the combustion chamber of a rapid compression and expansion machine, is compressed to ignite under various conditions of compression ratio, equivalence ratio, and injection timing. The characteristics of the resulting combustion and exhaust emissions are discussed in terms of the rate of heat release computed from the measured pressure, and the concentrations of THC, CO, and NOx are measured by FT-IR and CLD. The experimental data to date show that operation without knock is possible with mixtures of higher equivalence ratio when DME is directly injected rather than when it is inducted in the form of a perfectly homogeneous fuel-air mixture. Although fuel injected early in the compression stroke promotes homogeneity of the DME-air mixture in the cylinder, it causes the mixture to ignite too early to secure good thermal efficiency and knock-free operation at high loads. Low temperature reactions occur at about 660K regardless of the fueling methods, fuel injection timing and equivalence ratio. The main components of hydrocarbon emissions turned out to be unburned fuel (DME), formaldehyde and methane.  相似文献   
387.
A piezoelectric atomization device achieves fuel pressure modulation through vibration of a piezoelectric pressure modulator. As a consequence, the fast alternating and slow moving streams collide with each other and further break up the fuel drop. In this paper, an experimental investigation was carried out to study the fluid dynamic characteristics of the spray atomization process of automotive port fuel injectors with a piezoelectric pressure modulator. The investigation mainly focuses on: (a) the coupling characteristics between the piezoelectric stack and the hydraulic as well as the transfer characteristics of pressure modulation from the piezoelectric modulator to the point above the orifice; (b) the time history of the pressure dynamic response at the point above the orifice under a typical modulation frequency, which reflects the variation of pressure modulation while the fuel injector is working; and (c) the time-variation characteristics related to mechanical structure and fluid dynamics. The experimental results expose some important dynamic characteristics of pressure modulation, which will be very significant and lead us to greatly improve the fuel injection system, optimize the control parameters and implement spray atomization with a high quality performance in the near future.  相似文献   
388.
文中详细分析了我国第一个控制汽车燃料消耗的强制性国家标准--<乘用车燃料消耗量限值>实施以来所取得的效果;探讨了标准进一步严格的可行性和面临的问题;最后提出了几项政策建议,为国家制定相关政策提供参考.  相似文献   
389.
针对我国现行轻型汽车燃料消耗量试验方法,运用汽车工程理论进行了有关计算分析,指出该方法存在的不足.在从燃料经济性上评估、优选发动机、整车和发动机匹配设计方面,提出改进的建议和思路.  相似文献   
390.
柴油车微粒捕集器再生控制系统硬件设计   总被引:1,自引:0,他引:1  
控制系统在柴油车微粒捕集器再生过程中起着重要作用。采用“燃烧器+DOC+添加剂+DPF”的喷油助燃催化再生技术,设计了基于TMS320F2812单片机的再生控制系统硬件电路,分析了控制系统各硬件组成部分。实践证明,控制系统能够实现DPF可靠再生。  相似文献   
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