甲醇汽油对汽油机油清净分散性影响的试验研究

为了更好地推动甲醇汽油的应用,结合甲醇汽油及其燃烧产物的特点,通过实验室模拟试验,研究了甲醇汽油对汽油机油清净分散性的影响。试验结果表明:随着甲醇汽油中甲醇含量的增加,成焦量增大;甲醇汽油及其燃烧产物使汽油机油的清净分散能力有一定程度的降低;同等条件下,体积分数为25%~50%的甲醇汽油比其它含量的甲醇汽油对汽油机油清净分散性的影响更大。     

甲醇汽油对发动机油低温性能的影响

为考察甲醇汽油对发动机油低温性能的影响,通过向发动机油中添加甲醇汽油及其模拟燃烧产物甲酸、甲醛,分析其对油样的倾点、凝点、低温动力黏度的影响。结果表明:甲醇汽油及其模拟燃烧产物甲醛、甲酸对油样的倾点、凝点影响较小;随着甲醇添加量的增加,油样的低温动力黏度有增大的趋势;在甲酸质量分数为0.8%~1.2%时,油样的低温动力黏度值较大,但其增大的趋势平缓。因此甲醇汽油及其模拟燃烧产物对发动机油的低温性能影响不大。     

甲醇汽油对汽油机油氧化和硝化的影响

应用红外光谱技术,根据不同物质在红外光谱仪中的吸光度不同,研究了在汽油机油中加入不同配比和含量的甲醇、甲醛和甲酸对汽油机油的抗氧化性和抗硝化性的影响。结果表明,加入甲醇、甲醛和甲酸后的油样和汽油机油相比,氧化和硝化程度都增大了;加入甲醇汽油的油样和加入甲酸或甲醛的油样相比,硝化值和氧化值都比较大,表明甲醇汽油对汽油机油的抗氧化性和抗硝化性的影响最大,甲醛和甲酸的影响较小。     

甲醇裂解气对发动机爆震的影响

在基础燃料汽油机进气段加入少量甲醇裂解气,体积分数分别为1%;3%;5%,在一台四缸汽油发动机转速1400r/min。相同循环喷油量的稳态工况下,随着甲醇裂解气体积分数和乙醇体积分数的增加,燃烧缸压和放热率峰值逐渐降低,燃烧持续期逐渐增加,爆震得到有效抑制。     

钼添加量对Ni-8Al高温合金高温抗氧化性能的影响

采用粉末冶金技术制备了Ni-8Al-xMo(x=0,5,10,15,质量分数/%)高温合金,在1 000℃恒温氧化100h后,观察了氧化膜的表面和截面形貌,分析了其物相组成,研究了合金的高温抗氧化性能。结果表明:添加钼的试验合金高温抗氧化性能比未添加钼的更好;试验合金表面的氧化产物均主要为Al_2O_3和NiO,并有少量的NiAl_2O_4和NiMoO_4;当钼质量分数达到10%后,试验合金表面的氧化膜出现不同程度的剥落现象;当钼质量分数为5%时,试验合金的高温抗氧化性能最好。     

甲醇汽油发动机润滑油抗磨性试验研究

根据甲醇汽油对发动机润滑油抗磨性影响的要求,选用T203、T706、MoDDP抗磨添加剂,开发出一种甲醇汽油发动机润滑油;通过四球机试验考察各单剂对基础油抗磨性的影响,并采用正交试验方法分析各剂之间的复合性能。试验结果表明:当添加剂T203、MoDDP、T706的配比为1.5∶1.5∶0.4时,研制油的复合抗磨性能最佳。     

汽油添加剂对改善发动机性能的试验研究

本文叙述了汽油添加剂的主要作用和分类,并通过发动机台架试验研究了美狮汽油添加剂对发动机经济性及排气净化的影响,试验结果表明汽油中添加体积分数为01%的美狮汽油添加剂能够改善发动机经济性及排放性能。     

冷喷涂技术在甲醇水蒸气重整制氢中的应用

采用冷气体动力喷涂技术在铝基板上制备了铜涂层,并在该涂层上进行了甲醇水蒸气重整制氢试验;对重整试验前后的涂层表面及其断面形貌和组成进行了SEM和EDS分析.结果表明:重整制氢试验后涂层中的氧和铝元素含量增加,涂层表面形貌由层叠堆积状结构变为微球状多孔结构,孔隙率明显增加,重整产物中氢气体积分数可达74.9%,表明能用冷喷涂技术制备甲醇水蒸气重整制氢的催化涂层.     

MoS2、CdO及聚全氟乙丙烯填充改性聚四氟乙烯复合材料的摩擦磨损性能

用机械共混、冷压成型自由烧结的方法制备了MoS2、CdO和聚全氟乙丙烯填充聚四氟乙烯复合材料;用MM-2000型摩擦磨损试验机测试了在干摩擦条件下该复合材料的摩擦磨损性能;用扫描电镜(SEM)对磨损试样的表面形貌进行观察和分析.结果表明:未添加聚全氟乙丙烯的复合材料其摩擦磨损性能比添加的好;当CdO的体积分数为22.5%,MoS2的体积分数为7.5%时,复合材料的摩擦因数最小,抗磨性强,复合材料的摩擦磨损性能最佳.     

高组份含水甲醇汽油台架试验研究

通过台架试验将含水甲醇-汽油混合燃料（含水甲醇的体积分数分别为50%和60%,简称M50W、M60W）和93#汽油进行对比,研究了M50W、M60W燃料对汽油机动力性能、经济性能和排放性能的影响。试验研究表明,该台架上燃用M50W、M60W混合燃料对汽油机动力性影响不大,但汽油机有效热效率和燃油经济性提高,排温有所降低;CO排放减少,HC排放基本保持不变,NOx排放与燃用93#汽油相比有上升。     

含硼复合抗磨剂的摩擦学特性研究

含硼和不含硼两种新型减摩抗磨挤的摩擦学性能用四球和环－圆柱试验机进行了研究,试验结果表明,含硼抗磨降低油品的摩擦系数,减少磨损的性能更明显,并在实际行车试验中表现出良好的抗磨性能。     

甲醇汽油发动机油抗乳化性试验研究

甲醇汽油中甲醇吸水性强,要求甲醇汽油发动机油具有好的抗乳化性能。采用石油和合成液抗乳化性能测定仪研究抗乳化剂T1001、C405与清净分散剂、抗氧抗腐剂在基础油中的抗乳化性能。试验结果表明,T1001与基础油的感受性能良好,与分散剂、抗氧抗腐剂有协和作用,但与清净剂复配时产生沉淀;C405与清净分散剂、抗氧抗腐剂复合时的抗乳化性能比单独使用C405时有所降低。因此在研制甲醇汽油发动机油时,清净分散剂、抗氧抗腐剂与抗乳化剂复配时需慎重。     

公交汽车CNG/汽油两用燃料发动机油行车试验研究

选用CNG/汽油两用燃料公交汽车进行实车试验,考察了研制的公交汽车CNG/汽油两用燃料发动机油的实际使用性能。试验结果表明,该油品具有良好的高温清净性、低温分散性,良好的抗氧化以及抗磨性能,可以满足公交汽车CNG/汽油两用燃料发动机油的使用性能要求。     

The antiwear property of zinc dialkyldithiophosphates in used engine oils

The change in the lubrication properties of vehicle engine oils with driving distance was studied by using a cross-pin type of lubricant tester and a Fourier transform IR spectrometer. The effect of the thermal decomposition of zinc dialkyldithiophosphates (ZnDTPs) on their antiwear property was also examined. The amount of the ZnDTP in engine oil decreased and the amounts of the decomposition products increased with increasing running distance but a good antiwear property was still observed. After 60 h of heating at 135°C, the ZnDTP in sample oils had decomposed into a precipitate and the antiwear property of the oil had deteriorated. With sample oils containing ZnDTP and a detergent or a dispersant, the decomposition products dissolved in the oil and the antiwear property was maintained even after 80 h of heating. The results suggest that the decomposition products of ZnDTPs have a good antiwear property and that the good antiwear property of the used engine oils was retained because of the solubilization of decomposition products into the oil with the aid of a dispersant or a detergent.     

Changes in the mechanical properties of oil used in a gasoline engine

This study is concerned with the changes in and deterioration of the mechanical properties of oil used in a gasoline engine. The properties analysed were friction and antiwear performance, wear debris, load-carrying ability and the formation of surface films. It was found that the oil run in an engine deteriorated so as to increase the wear and friction and decrease the load-carrying ability as the running distance of oil was increased. The main cause of deterioration was related to the ability to form a protective film in the contact zone. When the film was produced by additives (sulphur), this could properly protect the surface in the contact zone undepleted from wear and friction. But as the oil deteriorated, it could not form such a film and so its protective ability on sliding surfaces diminished.     

二冲程汽油机油采用减摩抗磨添加剂的试验研究

本文通过对几种典型的发动机润滑油添加剂的对比试验，研究了此类减摩抗磨添加剂在二冲程汽油机油中的使用效果，试验结果表明某些添加剂在专用摩擦磨损试验机上的试验结果和发动机台架试验结果存在明显差异，据此本文提出了选用润滑油添加剂的建议。     

Comparison of engine oil degradation observed in laboratory alteration and in the engine by chemometric data evaluation

The influence of ethanol in gasoline and its partial combustion products on the engine oil performance was investigated by joint use of IR spectroscopic data and chemometrics. Oil samples obtained from artificial alteration in the laboratory and engine alteration in a chassis dynamometer were compared. Quantification of residual amounts of antioxidant and antiwear additive (ZDDP) in the oil samples by FTIR spectroscopy showed depletion of phenolic antioxidant during engine alteration but ZDDP degradation during artificial alteration. Different chemometrical models using principal component analysis (PCA) elucidated similarities and differences between both alteration types, proving the findings of FTIR spectroscopy. Additionally, laboratory-based artificial alteration was mainly driven by oxidative processes whereas engine alteration showed higher amounts of both oxidation and nitration products.