发动机下排气量大、机油耗高和断环问题的分析及改进

本文主要对某柴油机出现下排气量大、机油耗高及断环等问题的分析,通过对活塞环、活塞及缸套摩擦副的改进设计及试验验证,提出了＂下排气量大＂、＂机油耗高＂、＂断环＂、＂拉缸＂等问题的改进方案.     

影响单缸柴油机机油耗的因素及分析

以单缸蒸发冷却式柴油机为例，分析柴油机机油耗测试过程存在的各种影响因素及减少测试误差的措施。     

国Ⅳ重型柴油机降机油耗技术探讨

随着我国对排放要求不断提高,部分大城市开始实施国Ⅳ排放：如北京,上海等。针对我国实际情况采用SCR技术达国4排放要求是我国众多发动机厂采用的主流技术。但由于国4排放中对颗粒的要求只有国3颗粒的1/5：机油消耗中约有1/10转换为颗粒排放出来。那么如何降低机油耗成为能否采用该技术的关键。本文就是介绍如何对活塞、活塞环、气缸套及气缸体等相关零部件进行设计改进达到国4重型柴油机机油耗要求的。     

柴油机机油耗高的原因分析

针对最近市场反映的某机型柴油机机油耗率偏高的问题，进行试验分析，找出主要影响因素加以改进。     

活塞环对降低颗粒排放的影响

通过对目标发动机进行ESC 13工况测试分析,发现在燃烧状况良好的情况下,目标发动机的碳氢排放较高,导致颗粒(PM)排放不能满足排放法规的要求,经过分析,出现碳氢排放较高主要是由于柴油机烧机油。通过对影响PM排放的柴油机活塞环参数进行分析研究,改进了影响排放的活塞环主要参数,降低发动机的机油耗,从而改善了柴油机的PM排放。     

新型2.4L柴油机的国3排放开发

介绍了一种新型4缸2.4L国3排放柴油机燃烧系统(喷油器、缸盖、和活塞)的设计方案及参数的确定过程,最终的技术方案兼顾了柴油机的性能和生产成本.该新型发动机主要改进措施为:时间控制电控组合泵(最高喷射压力160MPa)替代了传统机械泵(最高喷射压力120MPa);燃烧室的改进设计;KS喷油嘴等的设计;降低机油耗的改进设计.采用以上改进措施后,发动机的排放、动力性、经济性同时达到了令人满意的效果:在排放符合国3标准的同时,升功率提高了8% ,整车15工况加权比油耗降低了12%.     

关于 TY395Q 柴油机窜机油问题分析

介绍窜机油问题及窜机油的一些现象，分析ＴＹ３９５Ｑ柴油机窜机油的原因，并给出了解决窜机油问题的一些措施。     

大功率柴油机状态监测仪开发研究

本文开发了一套柴油机状态监测仪,仪器由传感器、信号调理电路、单片机、外围电路、通讯电路、无线传输模块及智能显示模块组成。该系统能够实现对12路热电偶、1路压差、机油温度、密度、粘度及介电常数等信号进行采集和处理。处理后的数据可以通过智能显示模块、485总线及无线传输模块等方式实现显示和传输。系统可以方便的设置各监测参数的报警限值,当测试结果超过限值时,系统可以发出声光报警。通过试验对系统的功能进行了测试,结果表明系统功能完善、可靠性高,能够满足实际应用的需要。     

排气再循环对柴油机工作过程参数、性能和排放的影响

以 S195柴油机为例建立了排气再循环系统。在发动机台架试验的基础上 ,测量了采用排气再循环(EGR)对柴油机工作过程参数 pmax、dp/ dφ、着火延迟期τi、柴油机功率、燃油消耗率和排放的影响 ,提出了用废气容积比 REGR来评价和分析废气引入量的方法。结果表明 :EGR能显著降低柴油机排气中的NOx。此外 ,EGR在小负荷时使着火延迟期τi 缩短 ;大负荷时着火延迟期τi 有所延长。为了保证柴油机的性能指标 ,S195柴油机引入的废气容积比 REGR不应超过 2 0 %。     

模拟柴油机排气微粒的试验研究

为了改善柴油机排气微粒袋滤器性能试验的可控性及经济性，本文研制了一种微粒模拟装置，用以模拟柴油机的排气微粒。并采用气溶胶粒度电分析仪、扫描电镜、透射电镜等对模拟微粒影响柴油机微粒袋滤器性能的主要物理特性进行了测试，并与柴油机微粒的相应特性做了对比分析，证明所模拟的微粒具有与柴油机微粒相似的物理特性。因此可用本文研制的微粒模拟装置代替柴油机进行柴油机排气微粒袋滤器的性能试验。     

Properties and use of jatropha curcas oil and diesel fuel blends in compression ignition engine

In the present investigation the high viscosity of the jatropha curcas oil which has been considered as a potential alternative fuel for the compression ignition (C.I.) engine was decreased by blending with diesel. The blends of varying proportions of jatropha curcas oil and diesel were prepared, analyzed and compared with diesel fuel. The effect of temperature on the viscosity of biodiesel and jatropha oil was also studied. The performance of the engine using blends and jatropha oil was evaluated in a single cylinder C.I. engine and compared with the performance obtained with diesel. Significant improvement in engine performance was observed compared to vegetable oil alone. The specific fuel consumption and the exhaust gas temperature were reduced due to decrease in viscosity of the vegetable oil. Acceptable thermal efficiencies of the engine were obtained with blends containing up to 50% volume of jatropha oil. From the properties and engine test results it has been established that 40–50% of jatropha oil can be substituted for diesel without any engine modification and preheating of the blends.     

增压柴油机燃用不同掺比菜籽油甲酯的燃烧和排放的试验研究

在D6114ZLQB车用增压柴油机上比较研究了不同比例的菜籽油甲酯和0号柴油的混合燃料对发动机燃烧过程、燃油经济性和排放特性的影响。试验结果表明：燃用体积比低于15%的菜籽油甲酯,发动机的缸内燃烧过程和纯柴油基本一致;增压柴油机燃用菜籽油甲酯和柴油的混合燃料可以有效降低碳烟、HC和CO的排放;NOx排放略有上升;15%以内的菜籽油甲酯对柴油机燃料经济性影响很小。研究认为：增压柴油机相对自然吸气式柴油机具有更好的生物柴油燃料适应性;在不改变发动机参数的条件下,低比例的菜籽油甲酯具有良好的推广应用前景。     

Comparison of performance and emissions of diesel fuel,rapeseed and soybean oil methyl esters injected at different pressures

Fuel properties of rapeseed oil and soybean oil methyl esters (e.g. density, cetane number and viscosity etc.) are similar to those of the diesel fuel. These methyl esters can be used as diesel engine fuel by mixing withy diesel fuel. In this study a comparison of diesel fuel, the rapeseed oil methyl ester and the soybean oil methyl ester was made from the engine performance and emissions point of view. The tests were carried out with a four-cylinder diesel engine for tree different injection pressures such as 250, 300 and 350 bar with each of these fuels. For the purpose of comparison, tests were also conducted at full load conditions with diesel fuel. As the result, the performance and emission values of rapeseed oil (R) and soybean oil (S) methyl esters were found to be nearly the same with those of diesel fuels (D) when injection pressure was increased to 300 bar.     

柴油机机油压力不足的主要原因及解决办法

以S1110为例阐述机油泵、机体、轴承、曲轴、主轴承盖、连杆以及装配工装等对柴油机机油压力不足的影响。其中涉及使用后的柴油机以及柴油机制造企业应注意的问题，并就一些主要因素提出解决办法。     

柴油/CNG双燃料发动机开发及其性能分析

在CA6113BZS-60柴油机的基础上，设计开发了CA6113BN-01柴油／CNG双燃料发动机，并对开发的双燃料发动机进行了动力性能和经济性能的实验与分析．结果表明，开发的混合器混合和机械控制引燃柴油量及由进气管压力调节控制天然气量的双燃料发动机，具有全负荷速度特性扭矩储备大及各种负荷下天然气替代率变化较小，综合柴油替代率高，结构简单和成本低等优点，并具有良好的动力性能和经济性能指标，操作性好，可随时恢复纯柴油运行并能够基本保持原柴油机的性能．     

Investigations on the performance and exhaust emissions of a diesel engine using preheated waste frying oil as fuel

In the present experimental investigation, waste frying oil a non-edible vegetable oil was used as an alternative fuel for diesel engine. The high viscosity of the waste frying oil was reduced by preheating. The properties of waste frying oil such as viscosity, density, calorific value and flash point were determined. The effect of temperature on the viscosity of waste frying oil was evaluated. It was determined that the waste frying oil requires a heating temperature of 135 °C to bring down its viscosity to that of diesel at 30 °C. The performance and exhaust emissions of a single cylinder diesel engine was evaluated using diesel, waste frying oil (without preheating) and waste frying oil preheated to two different inlet temperatures (75 and 135 °C). The engine performance was improved and the CO and smoke emissions were reduced using preheated waste frying oil. It was concluded from the results of the experimental investigation that the waste frying oil preheated to 135 °C could be used as a diesel fuel substitute for short-term engine operation.     

Performance and emission characteristics of a diesel engine fueled with coconut oil–diesel fuel blend

The objective of the present study is to reveal the effects of pure coconut oil and coconut oil–diesel fuel blends on the performance and emissions of a direct injection diesel engine. Operation of the test engine with pure coconut oil and coconut oil–diesel fuel blends for a wide range of engine load conditions was shown to be successful even without engine modifications. It was also shown that increasing the amount of coconut oil in the coconut oil–diesel fuel blend resulted in lower smoke and NO_x emissions. However, this resulted in an increase in the BSFC. This was attributed to the lower heating value of neat coconut oil fuel compared to diesel fuel.     

Using of cotton oil soapstock biodiesel–diesel fuel blends as an alternative diesel fuel

In this study, usability of cotton oil soapstock biodiesel–diesel fuel blends as an alternative fuel for diesel engines were studied. Biodiesel was produced by reacting cotton oil soapstock with methyl alcohol at determined optimum condition. The cotton oil biodiesel–diesel fuel blends were tested in a single cylinder direct injection diesel engine. Engine performances and smoke value were measured at full load condition. Torque and power output of the engine with cotton oil soapstock biodiesel–diesel fuel blends decreased by 5.8% and 6.2%, respectively. Specific fuel consumption of engine with cotton oil soapstock–diesel fuel blends increased up to 10.5%. At maximum torque speeds, smoke level of engine with blend fuels decreased up to 46.6%, depending on the amount of biodiesel. These results were compared with diesel fuel values.     

琅驰客车柴油发动机的使用、维护和保养

主要论述了琅驰客车柴油发动机使用过程中的注意事项,如柴油、机油、冷却液的选用以及起动、停车的要求等。并对琅驰客车柴油发动机的维护和保养作了详细的介绍。为大家能正确使用、维护和保养此发动机提供依据。     

柴油公交大巴机油更换周期的研究

针对深圳市柴油公交大巴的机油更换周期进行研究,对试验车辆所使用的新机油、更换时的机油进行取样,并且对决定机油质量的指标参数进行检测.对决定机油更换周期的运动黏度变化率(100℃)、闪点(闭口)、碱值下降率、正戊烷不溶物、水分、铁含量、铜含量、铝含量、硅含量等项目进行分析.根据分析结果得出柴油公交大巴合理的机油更换周期,...