浅谈安庆—大发DK—20系列柴油机的NOx排放控制

本文简要介绍了DK－20系列柴油机NOx排放控制的有关问题，对与排放有关的零部件作了简要说明，同时介绍了DK－20系列柴油机NOx排放的检测。     

用排气再循环降低柴油机氮氧化物排放的探讨

本文阐明了控制柴油机氮氧化物的必要性,介绍了氮氧化物的生成机理,讨论了控制柴油机氮氧化物排放的各种措施,并对应用排气再循环降低氮氧化物的技术措施进行了重点探讨,提出了作者的初步设想.     

柴油机尾气氮氧化物的机外净化技术研究(二)

综述车用柴油机氮氧化物机外治理的现状和发展趋势,介绍了降低柴油机NOx排放的机外措施：稀NOx技术、选择性催化还原技术、NOx的吸附技术及等离子体技术,分析了各种技术措施的各自特点和存在的问题。     

柴油机机内净化的排放试验研究

利用机内净化技术对某增压中冷柴油机进行国Ⅲ开发的排放试验研究。技术措施包括：采用更高喷射压力机械喷油泵、小孔径无压力室喷油器、降低机油消耗率等改进方案优化柴油机燃烧,降低颗粒（PM）排放;通过推迟供油提前角、废气再循环技术,降低氮氧化物（NOx）排放。试验表明,综合实施以上方案,柴油机能够满足国Ⅲ排放法规限值要求,具有良好的市场应用前景。     

陕柴-大发DK28系列柴油机

本文较为全面地介绍了陕柴-大发DK28系列柴油机,其中阐述了该型机的结构特点和性能指标以及在DL28柴油机的基础上所进行的一些结构设计改进。     

柴油机尾气氮氧化物的机外净化技术研究(一)

综述车用柴油机氮氧化物机外治理的现状和发展趋势，介绍了降低柴油机NOx排放的机外措施：稀NOx技术、选择性催化还原技术、NOx的吸附技术及等离子体技术，分析了各种技术措施的各自特点和存在的问题。     

中速船用柴油机NOx排放控制技术及其测试认证

详细介绍了国际海事组织(IMO)关于船用柴油机NOx排放的限制规范,以及基于IMO规范的排放测试、认证程序,并结合广州柴油机厂230、320两个系列的柴油机产品通过排放测试的经验,对氮氧化物NOx的形成机理及其控制技术进行了分析探讨.     

高速车用柴油机废气再循环系统

采用废气再循环来降低氮化物的排放，目前已成为轻型车和轿车用柴油机排放达标的重要措施，本文以英国福特汽车公司在其1.8LTCI轿车用柴油机上所采用的废气再循环系统为例，详细介绍了相同类型的柴油机所用的废气再循环的控制原理，工作特点及其故障诊断的方法，为我国柴油机更好地利用这一技术来减少氮氧化物排放以满足日趋严格的排放法规提供一些借鉴。     

柴油机实行复合燃烧的试验研究

以柴油机为基础。以LPG或甲醇作为预混合燃料,与喷入的柴油组成部分预混的复合燃烧,大幅度降低了发动排气烟度,同时使氮氧化物排放得到一定改善,发动机的比油耗优于原柴油机,而排气中的未燃烃HC和CO的浓度有所提高,甲醇比LPG具有降低烟度效果更好、氮氧化物降低更多和HC排放相对较低的优越性。     

6DK28e柴油机发电机组游车故障分析及排除

针对6DK28e柴油机发电机组游车故障,从高压油泵齿条、调速器、调速器滑油油位等几方面进行分析排查。排查结果表明:造成6DK28e柴油机发电机组游车的原因系调速器传动齿轮间隙超差、调速器花键传动轴异常磨损、调速器花键联轴节尺寸不合理、调速器滑油油位过高。据此提出了相应的改进措施。     

Use of hydrogen in dual-fuel diesel engines

Hydrogen is a promising future energy carrier due to its potential for production from renewable resources. It can be used in existing compression ignition diesel engines in a dual-fuel mode with little modification. Hydrogen's unique physiochemical properties, such as higher calorific value, flame speed, and diffusivity in air, can effectively improve the performance and combustion characteristics of diesel engines. As a carbon-free fuel, hydrogen can also mitigate harmful emissions from diesel engines, including carbon monoxide, unburned hydrocarbons, particulate matter, soot, and smoke. However, hydrogen-fueled diesel engines suffer from knocking combustion and higher nitrogen oxide emissions. This paper comprehensively reviews the effects of hydrogen or hydrogen-containing gaseous fuels (i.e., syngas and hydroxy gas) on the behavior of dual-fuel diesel engines. The opportunities and limitations of using hydrogen in diesel engines are discussed thoroughly. It is not possible for hydrogen to improve all the performance indicators and exhaust emissions of diesel engines simultaneously. However, reformulating pilot fuel by additives, blending hydrogen with other gaseous fuels, adjusting engine parameters, optimizing operating conditions, modifying engine structure, using hydroxy gas, and employing exhaust gas catalysts could pave the way for realizing safe, efficient, and economical hydrogen-fueled diesel engines. Future work should focus on preventing knocking combustion and nitrogen oxide emissions in hydrogen-fueled diesel engines by adjusting the hydrogen inclusion rate in real time.     

Improvement of emission reduction in nano additive Simarouba glauca biodiesel blends

In this paper discussed about the emission profile from nano additive blended biodiesel. It is observed that minimum carbon dioxide was emitted in the presence of zinc oxide blends when compared to B20 and diesel. The hydrocarbon emission for the diesel and B20 was higher than that of the B20ZnO50 and B20ZnO100 blended fuels. The higher oxide of nitrogen emissions was observed with the B20ZnO50 and B20ZnO100 blended fuels at all engine loads when compared to B20 and diesel.     

Emissions from sawdust biomass and diesel blends fuels

Biomass producer gas presents a very promising alternative fuel to diesel since it is a renewable and clean burning fuel having similar properties to those of diesel. In this outline, a multi-cylinder diesel engine is experimentally optimized for maximum diesel savings, lower emissions, and without any excessive vibration of the engine using sawdust biomass as producer gas. Emission parameters of the double-fuel engine at diverse gas flow rates are contrasted with those of diesel at distinctive load conditions. The study brings out that the greatest diesel reserve happens to be 80% at 8 kW load without any engine issue in dual-fuel mode. Carbon monoxide (CO), hydrocarbon (HC), and carbon dioxide (CO₂) emissions in dual-fuel mode are more contrasted with diesel at all test extents. Smoke opacity and oxide of nitrogen (NO) emission values in dual-fuel mode are less contrasted with diesel.     

Experimental investigations of performance and emissions of Karanja oil and its blends in a single cylinder agricultural diesel engine

An experimental investigation has been carried out to analyze the performance and emission characteristics of a compression ignition engine fuelled with Karanja oil and its blends (10%, 20%, 50% and 75%) vis-a-vis mineral diesel. The effect of temperature on the viscosity of Karanja oil has also been investigated. Fuel preheating in the experiments – for reducing viscosity of Karanja oil and blends has been done by a specially designed heat exchanger, which utilizes waste heat from exhaust gases. A series of engine tests, with and without preheating/pre-conditioning have been conducted using each of the above fuel blends for comparative performance evaluation. The performance parameters evaluated include thermal efficiency, brake specific fuel consumption (BSFC), brake specific energy consumption (BSEC), and exhaust gas temperature whereas exhaust emissions include mass emissions of CO, HC, NO and smoke opacity. These parameters were evaluated in a single cylinder compression ignition engine typically used in agriculture sector of developing countries. The results of the experiment in each case were compared with baseline data of mineral diesel. Significant improvements have been observed in the performance parameters of the engine as well as exhaust emissions, when lower blends of Karanja oil were used with preheating and also without preheating. The gaseous emission of oxide of nitrogen from all blends with and with out preheating are lower than mineral diesel at all engine loads. Karanja oil blends with diesel (up to 50% v/v) without preheating as well as with preheating can replace diesel for operating the CI engines giving lower emissions and improved engine performance.     

Emission analysis of different blends of karanja oil with producer gas in a twin-cylinder diesel engine in dual fuel mode

The present study describes the emission analysis of different blends of karanja oil and diesel with producer gas in dual fuel mode using a twin-cylinder diesel engine in two cases of operations. In case 1, the above fuels are tested in single mode and in dual fuel mode operation at an optimum gas flow rate of 21.49 Kg/h under different load conditions. Similarly, in case 2 the same test fuels are used in dual fuel mode only at an optimum load of 10 kW under different gas flow rates. The study reveals that dual fuel operation of all test fuels shows lower smoke and oxide of nitrogen emissions compared to their single mode operation, whereas other emission parameters are on the higher side. However, all blended fuels show better emissions compared to diesel in both cases of operations.     

Factors affecting emissions from diesel fuel and water-in-diesel emulsion

The purpose of this research is to investigate the effect of addition of surfactant and water in diesel and to make an emulsified fuel considering the needs for vehicle performance and its cleanest possible operation. The total surfactant concentration in each of the diesel-water emulsion samples studied (span 20, span 80, tween 20, tween 80) is fixed at 1% w/w. The water content is variable at 5–15% w/w and the diesel content is varied from 84 to 94% w/w. Among all the tested nonionic surfactants, tween 80 is found to prominently reduce the carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxide (NOx) emissions. Tween 20 reduced the NOx emission to a greater extent. Diesel emulsion with a fixed ratio of span 80 and tween 80 (1:1) efficiently reduced the overall emissions as compared to diesel alone. The developed diesel emulsion employed with nonionic surfactants clearly reduced the harmful engine emissions such as CO, HC, and NOx, signifying them as a future potential emulsifier in diesel fuel emulsion.     

不同海拔下VGT对含氧燃料柴油机性能的影响

利用大气压力模拟装置,试验研究了可变几何截面涡轮增压器(VGT)对高压共轨柴油机分别燃用纯柴油和生物柴油-乙醇-柴油(BED)含氧燃料的经济性、排放特性及燃烧特性的影响。结果表明:随着海拔的升高,柴油机经济性恶化,氮氧化物(NO_x)排放降低,而一氧化碳(CO)和碳氢化合物(HC)排放及烟度升高。燃用纯柴油与含氧燃料,随着VGT喷嘴环开度的增大,柴油机的经济性均有不同程度的恶化,而CO、HC排放及排气烟度也都有不同程度的升高。在高海拔地区,燃用纯柴油的经济性优于含氧燃料,但使用含氧燃料有助于改善柴油机的CO、HC排放及烟度。在中等负荷工况下,NO_x排放随着VGT喷嘴环开度的增大呈现先减小后增大的趋势;在高负荷工况下,放热率峰值和最高气缸压力均随着VGT喷嘴环开度的增大而降低,从而降低了NO_x排放。     

Oxides of nitrogen emissions from biodiesel-fuelled diesel engines

Biodiesel has received, and continues to receive, considerable attention for its potential use as an augmenting fuel to petroleum diesel. Its advantages include decreased net carbon dioxide, hydrocarbon, carbon monoxide, and particulate matter emissions, and fuel properties similar to petroleum diesel for ease of use in diesel engines. Its disadvantages include poorer cold flow characteristics, lower heating values, and mostly reported higher emissions of oxides of nitrogen (NO_x = NO + NO₂, where NO is nitric oxide and NO₂ is nitrogen dioxide). This latter disadvantage (i.e., higher emissions of oxides of nitrogen) is the focus of this review article. NO_x formation mechanisms are complex and affected by several different features (e.g., size, operating points, combustion chamber design, fuel system design, and air system design) of internal combustion engines. The slight differences in properties between biodiesel and petroleum diesel fuels are enough to create several changes to system and combustion behaviors of diesel engines. Combined, these effects lead to several complex and interacting mechanisms that make it difficult to fundamentally identify how biodiesel affects NO_x emissions. Instead, it is perhaps better to say that several parameters seem to most strongly influence observed differences in NO_x emissions with biodiesel, thus introducing several possibilities for inconsistency in the trends. These parameters are injection timing, adiabatic flame temperature, radiation heat transfer, and ignition delay. This article provides a review of the rich literature describing these parameters, and provides additional insight into the system responses that are manifested by the use of biodiesel.     

Emission analysis of different blends of karanja biodiesel with producer gas in a twin cylinder diesel engine in dual fuel mode

The present study demonstrates the emission analysis of different blends of Karanja biodiesel and diesel with producer gas in dual fuel mode using a twin cylinder diesel engine for two cases of operations. In case 1, a test is carried out using the above test fuels both in single mode and dual fuel mode operation with a constant gas flow rate of 21.49 Kg/h under different load conditions. Similarly, in case 2, a test is performed at a constant load of 10 kW under different gas flow rates using the same test fuels in the dual fuel mode only. The study reveals that all blended fuels show better emissions compared to diesel in both cases of operations. Dual fuel mode operation of all tested fuels shows lower smoke and oxide of nitrogen emissions compared to their single mode operation under all load conditions, whereas other emission parameters are found to be on the higher side.