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91.
Alfred Zeman 《Lubrication Science》1988,5(2):133-148
The versatility of a differential scanning calorimetry (DSC) cell in studying thermal and/or thermal-oxidative degradation of lubricants is shown using ester-based aviation turbine oils as an example. The following applications are discussed: 1. quality control of fresh and used oils by pressure differential scanning calorimetry; 2. influence of metal catalysis on oil degradation; 3. identification of volatile degradation products by PDSC gas chromatography-mass spectrometry via a TENAX trap; 4. determination of spontaneous ignition temperatures; 5. influence of metall metal oxides, wear debris and oil degradation products on ignition behaviour; 6. inhibition of spontaneous ignition by antioxidants. 相似文献
92.
火力发电厂锅炉点火系统采用等离子点火及稳燃技术,引起供电负荷及厂用电系统变化,为使等离子装置供电电源的安全可靠,对其负荷分析并提出原则性供电方式意见供大家探讨。 相似文献
93.
采用定向关联图误差传播敏感度分析法(DRGEPSA)、同分异构体合并和峰值浓度分析法对正丁醚和正辛醇的详细机理进行简化,并将简化后的正丁醚和正辛醇机理合并,获得了包含117个组分和601个基元反应的骨架机理.利用正丁醚和正辛醇详细机理的着火延迟、正丁醚层流火焰速度的试验数据和正辛醇在射流搅拌反应器(JSR)中组分摩尔浓... 相似文献
94.
Spark-less jet ignition pre-chambers are enablers of high efficiencies and load control by quantity of fuel injected when coupled with direct injection of main chamber fuel, thus permitting always lean burn bulk stratified combustion. Towards the end of the compression stroke, a small quantity of hydrogen is injected within the pre-chamber, where it mixes with the air entering from the main chamber. Combustion of the air and fuel mixture then starts within the pre-chamber because of the high temperature of the hot glow plug, and then jets of partially combusted hot gases enter the main chamber igniting there in the bulk, over multiple ignition points, lean stratified mixtures of air and fuel. The paper describes the operation of the spark-less jet ignition pre-chamber coupling CFD and CAE engine simulations to allow component selection and engine performance evaluation. 相似文献
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针对摩托车发动机经济性差、排放高的问题,笔者在一台加装了双火花塞和进气补气系统的单缸摩托车发动机上,在不同转速条件下,就双火花塞点火和补气对内燃机燃烧与排放特性的影响进行了试验研究。试验结果表明,采用双点火配合进气补气的方法可以有效降低发动机CO、HC排放及比燃油消耗率。在转速为3500r.min-1的条件下,采用双点火配合进气补气的发动机比燃油消耗率较原机降低约12.5%。在发动机转速高于3000r.min-1时,采用双点火也可以在一定程度上改善发动机经济性并降低CO和HC排放。但NOx排放在双点火条件下较原机略有升高。 相似文献
98.
Anil Singh Bika Luke FranklinDavid B. Kittelson 《International Journal of Hydrogen Energy》2011,36(8):5143-5152
Varying proportions of hydrogen and carbon monoxide (synthesis gas) have been investigated as a spark ignition (SI) engine fuel in this paper. It is important to understand how various synthesis gas compositions effect important SI combustion fundamentals, such as knock and burn duration, because in synthesis gas production applications, the compositions can vary significantly depending on the feedstock and production method.A single cylinder cooperative fuels research (CFR) engine was used to investigate the knock and combustion characteristics of three blends of synthesis gas (H2/CO ratio); 1) 100/0, 2) 75/25, and 3) 50/50, by volume. These blends were tested at three compression ratios (6:1, 8:1, and 10:1), and three equivalence ratios (0.6, 0.7, and 0.8).It was revealed that the knock limited compression ratio (KLCR) of a H2/CO mixture increases with increasing CO fraction, for a given spark timing. For a given equivalence ratio and spark timing, a 50%/50% H2/CO mixture produced a KLCR of 8:1 compared to a 100% H2 condition, which produced a KLCR of 6:1. The burn duration and ignition lag is also increased with increasing CO fraction. The results from this work are important for those considering using synthesis gas as a fuel in SI engines. It reveals that although CO is a slow burning fuel, higher CO fractions in synthesis gas can be beneficial, because of its increased resistance to knock, which gives it the potential of producing higher indicated efficiencies through the utilization of an engine with a higher compression ratio. 相似文献
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