2013年CIMAC大会介绍(三)

<正>张贴论文议题1:产品开发一柴油机64:进气密度和氧浓度对高负荷柴油机在高负荷工况下热效率和排放的影响105:大型二冲程船用柴油机模拟的半试验建模法338:高涡轮增压四冲程柴油机性能因分轴式涡轮增压废气系统得到进一步提高议题2:产品开发一气体机和双燃料发动机204:船用发动机的双燃料模式295:米勒循环对火化点火气体机的影响297:火花塞位置对火花点火燃烧性能的影响348:基于AVL-Boost的气体发动机开发议题3:基础工程123:基于AVL Boost的4190系列船用柴油机整体性能优化的模拟研究246:进气温度对双燃料HCCI燃烧式发动机燃烧和排放的影响293:扭振测试技术的对比分析340:缸套预紧变形和结构的影响因素研究360:船用中速柴油机上止点确定方法的试验研究     

柴油-甲醇组合燃烧技术在发电机组产品开发中的应用

对一台增压中冷柴油机进行改装,使其采用柴油-甲醇组合燃烧（Diesel-Methanol Compound Combustion,DMCC）方式运行。发动机台架以及装机运行试验的结果表明：发动机的双燃料模式平稳、可靠,动力性与原纯柴油相同,调速特性满足机组使用要求;与纯柴油相比,双燃料模式的燃料经济性在中高负荷时显著提升,在低负荷时较低;双燃料模式下的碳排放比在纯柴油工况下的碳排放降低约11.4%,PM和NO_x排放明显低于纯柴油模式,NO_x排放需要进一步优化;全工况下CO和HC排放量均大幅增加,所以为满足法规需要加装后处理系统;按照机组视在功率为300 kW运行时,双燃料模式的燃料经济性改善14.5%,大幅度降低发电成本。     

船用中速柴油机双燃料改造技术应用研究

本文介绍了船用中速柴油机双燃料改造技术应用研究,包括柴油机改造、燃气阀研制、控制系统研制,并进行了双燃料发动机台架试验。试验表明:所改造后的双燃料机运行安全、稳定,最高替代率可达75%以上;GAV200燃气喷射阀工作可靠,一致性良好,满足发动机工作需求;控制系统性能可靠,实现了双燃料发动机的替代率控制、运行参数实时监控、运行数据保存以及故障诊断与保护等功能,顺利获得CCS证书,实现工程化应用。     

船用中速柴油机预测模型的自动标定与优化

为解决柴油机预测模型参数过多导致的标定困难问题，采用遗传基因算法对搭建的船用中速机DIjet预测燃烧模型进行智能标定。借助最大缸内压力以及对应的曲轴转角快速完成缸压曲线标定，相较于传统手动标定，标定时间可缩短到几十分之一。在进行柴油机整体功率验证后，对NO_x排放进行标定，形成一套简便可行的智能标定流程。在完成标定的模型上进行NO_x排放及有效燃油消耗率（brake specific fuel consumption，BSFC）优化，在考虑两者不同权重系数的情况下得到更优的帕累托前沿面。     

MAN ES计划于2024年将使用甲醇燃料的四冲程发动机解决方案推向市场

<正>MAN Energy Solutions已经宣布,计划在2024年之前将可使用甲醇的双燃料中速发动机推向市场,并预计在2023年推出面向固定市场的双燃料氢发动机。随后,为满足市场需求,可使用氨气的中速双燃料发动机也将推出。MAN Energy Solutions四冲程船用发动机部门负责人Marita Krems在一份声明中解释说:“发动机制造商正在采取分阶段方法引入双燃料解决方案。     

船用中速柴油机废气再循环技术研究

废气再循环(EGR)技术是船用中速柴油机应对IMO Tier III排放法规的重要技术措施。本文以船用中速单缸柴油机为研究对象,开展了牺牲某缸的EGR系统中被牺牲气缸的工作过程、性能及排放特性的试验及仿真研究,研究结果可为船用中速柴油机克服进排气压力逆差关键技术的方案选择提供一定的技术依据。     

Wartsila 20DF双燃料中速发动机获两艘船的订单

正面对美国市场持续上升的天然气发动机需求,Wartsila公司推出20DF双燃料中速发动机作为有效回应。20DF双燃料发动机可应对严格的排放政策——EPA Tier4。随着2012年8月北美排放控制区域(ECA)的强制执行,该发动机技术吸引了全球在ECA通行的船东。20DF双燃料中速发动机单机功率为     

新型燃油系统在船用柴油机降排放中的应用

针对降低船用柴油机NO_x排放的同时降低技术改造成本的要求,提出了一种新型燃油系统,即调压孔式喷油泵和交叉喷孔油嘴结合的燃油喷射系统。试验验证表明:该新型燃油系统可实现靴形喷射规律并改善燃油雾化,NO_x排放大幅降低。     

基于稳态流场的天然气喷嘴布置研究

为了满足越来越严格的排放要求,船用柴油机改造为由柴油引燃的柴油-天然气双燃料发动机已成为趋势。针对4190Z_LC船用中速柴油机,确定了天然气喷嘴在进气歧管上的安装位置,在实验验证正确的进气道模型的基础上,补充完善进气管和天然气喷嘴的几何模型;利用AVL_FIRE仿真软件平台,对采用不同天然气喷嘴布置方案时的稳态流场进行模拟计算,通过对比分析进气道和气缸内天然气与空气的混合情况,得到较优喷嘴设计方案。研究结果显示:为了得到更均匀的缸内天然气与空气的混合气,在同等总喷孔面积的基础上,应尽量增多喷孔数目,天然气应顺向喷射,天然气的喷嘴应在进气道中偏低安装。我们的研究为该机的双燃料机型改造提供理论基础。     

机电联合控制LPG-柴油双燃料增压发动机的研究

对增压柴油机燃用 L PG-柴油双燃料、采用 2种机电联合控制方案进行了较为深入的研究 ,对比分析了原柴油机和机电联合控制 L PG-柴油双燃料发动机的动力性、燃料经济性和碳烟、NOx、CO、HC排放。机电联合控制方案 1的试验研究表明 :掺烧 L PG后 ,可以显著地降低柴油机的碳烟排放 ;但在小负荷范围内 ,燃料消耗率略有增加 ,HC、CO排放增加较多。机电联合控制方案 2的试验研究表明 :双燃料发动机和原柴油机外特性相比 ,转矩几乎不降低 ,燃料消耗率略有下降 ,碳烟排放显著降低 ,NOx、CO排放变化不大 ,HC排放增加 ;双燃料发动机和原柴油机负荷特性相比 ,燃料消耗率在小负荷范围内持平而在中等以上负荷略有下降 ,碳烟排放显著降低 ,NOx 排放变化不大 ,HC、CO排放在小负荷范围内基本相同而在中等以上负荷略有增加。     

Vegetable oils as renewable fuels for power plants based on low and medium speed diesel engines

There is a high potential for plant oils as alternative fuel for low and medium speed diesel engines, making petroleum-derived fuels likely to be replaced in these types of engines. Vegetable oils have important advantages over both heavy fuel oil (HFO) and marine gas oil (MGO), the fuels currently used in diesel power plants by large two stroke low-speed diesel engines and by medium speed diesel engines, respectively. The emission of certain pollutants and greenhouse gases like SO_x, soot and, mainly, CO₂ can be reduced by using vegetable oils in these types of engines. This work discusses the potential of vegetable oils as fuel for power plant diesel engines and the problems that can be derived from their use. Current experiences with medium speed diesel engines together with the analysis carried out in this paper indicate that vegetable oils can substitute HFO and MGO, without almost any engine modification.     

The effect of clove oil and diesel fuel blends on the engine performance and exhaust emissions of a compression-ignition engine

Diesel engines provide the major power source for transportation in the world and contribute to the prosperity of the worldwide economy. However, recent concerns over the environment, increasing fuel prices and the scarcity of fuel supplies have promoted considerable interest in searching for alternatives to petroleum based fuels. Based on this background, the main purpose of this investigation is to evaluate clove stem oil (CSO) as an alternative fuel for diesel engines. To this end, an experimental investigation was performed on a four-stroke, four-cylinder water-cooled direct injection diesel engine to study the performance and emissions of an engine operated using the CSO–diesel blended fuels. The effects of the CSO–diesel blended fuels on the engine brake thermal efficiency, brake specific fuel consumption (BSFC), specific energy consumption (SEC), exhaust gas temperatures and exhaust emissions were investigated. The experimental results reveal that the engine brake thermal efficiency and BSFC of the CSO–diesel blended fuels were higher than the pure diesel fuel while at the same time they exhibited a lower SEC than the latter over the entire engine load range. The variations in exhaust gas temperatures between the tested fuels were significant only at medium speed operating conditions. Furthermore, the HC emissions were lower for the CSO–diesel blended fuels than the pure diesel fuel whereas the NO_x emissions were increased remarkably when the engine was fuelled with the 50% CSO–diesel blended fuel.     

Effect of hydrogen supplementation on engine performance and emissions

Vehicular Pollution and environmental degradation are on the rise with increasing vehicles and to stop this strict regulation have been put on vehicular emissions. Also, the depleting fossil fuels are of great concern for energy security. This has motivated the researchers to invest considerable resources in finding cleaner burning, sustainable and renewable fuels. However renewable fuels independently are not sufficient to deal with the problem at hand due to supply constraints. Hence, advanced combustion technologies such as homogeneous charge compression ignition (HCCI), low-temperature combustion (LTC), and dual fuel engines are extensively researched upon. In this context, this work investigates dual fuel mode combustion using a constant speed diesel engine, operated using hydrogen and diesel. The engine is operated at 25, 50 and 75% loads and substitution of diesel energy with hydrogen energy is done as 0, 5, 10 and 20%. The effect of hydrogen energy share (HES) enhancement on engine performance and emissions is investigated. In the tested range, slightly detrimental effect of HES on brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) is observed. Comparision of NO and NO₂ emissions is done to understand the non-thermal influence of H₂ on the NO_x emissions. Hence, HES is found beneficial in reducing harmful emissions at low and mid loads.     

Effect of addition of di-tert butyl peroxide (DTBP) on performance and exhaust emissions of dual fuel diesel engine with hydrogen as a secondary fuel

Today, the world faces a number of challenges on global level. The optimum replacement for fossil fuels is one of these challenges. Hydrogen in the past has been and continues to be used by numerous researchers in diesel engines. However, high NO_x emissions and low replacement of hydrogen fuel are the concern with many researchers. In the present study, di-tert butyl peroxide (DTBP) has been used as an additive in diesel fuel, to investigate the performance and exhaust emissions of the diesel engine working on dual fuel mode by using hydrogen as secondary fuel. At low, medium and high load conditions, the maximum increase in brake thermal efficiency was observed to be 87.50%, 14.68% and 5.89% respectively for 1%, 3% and 5% of additive (DTBP) by 40% of hydrogen fuel substitution, as compared to diesel fuel operation. Moreover, by addition of 4% di-tert butyl peroxide (DTBP) in diesel engine working on dual fuel mode showed 33.82%, 10.27% and 29.27% reduction in NO_x emission at low, medium and high load conditions respectively at 40% hydrogen substitution, as compared to dual fuel operation using hydrogen as secondary fuel without additives. By addition of 5% additive (DTBP) at 69% load condition and 40% hydrogen substitution, reduces CO emissions by 38.66% as compared to dual fuel operation, using hydrogen as secondary fuel.     

10 MW级中速大功率柴油机开发

主要介绍10 MW级中速大功率柴油机12 MV390的开发研制过程,着重在其技术特征及详细开发设计过程,包括总体设计、系统布置,零部件结构设计、详细技术特征,以及整机试验情况。试验结果表明:12MV390样机的油耗及排放性能均达到国际先进水平,综合性能指标与当前大功率柴油机的技术发展趋势基本一致。在该机型的研发中大量采用了现代开发工具,极大地缩短了产品开发周期;建立起的柴油机自主研发设计平台实现了大功率中速柴油机研发技术及经验的沉淀。     

Experimental investigation of the combustion characteristics,emissions and performance of hydrogen port fuel injection in a diesel engine

Diesel engines are indispensable in daily life. However, the limited supply of petroleum fuels and the stringent regulations on such fuels are forcing researchers to study the use of hydrogen as a fuel. In this study, a diesel engine is operated using hydrogen–diesel dual fuel, where hydrogen is introduced into the intake manifold using an LPG-CNG injector and pilot diesel is injected using diesel injectors. The energy contents of the total fuel, 0%, 16%, 36% and 46% hydrogen (the 0% hydrogen energy fraction represents neat diesel fuel), were tested at 1300 rpm of constant engine speed and 5.1 kW of constant indicated power. According to test results, the indicated thermal efficiency of the engine decreases and the isfc increases with an increasing hydrogen energy fraction. Additionally, indicated specific CO, CO₂ and smoke emissions decrease with an increasing percentage of hydrogen fuel. However, indicated specific NO_x emissions do not change at the 16% hydrogen energy fraction, in other words, with an increase in the hydrogen amount (36% and 46% hydrogen energy fraction of total fuel), a dramatic increase (58.8% and 159.7%, respectively) is observed. Additionally, the peak in-cylinder pressure and the peak heat release rate values increase with the increasing hydrogen rate.     

Effect of manifold injection of hydrogen gas in producer gas and neem biodiesel fueled CRDI dual fuel engine

The high flammability of hydrogen gas gives it a steady flow without throttling in engines while operating. Such engines also include different induction/injection methods. Hydrogen fuels are encouraging fuel for applications of diesel engines in dual fuel mode operation. Engines operating with dual fuel can replace pilot injection of liquid fuel with gaseous fuels, significantly being eco-friendly. Lower particulate matter (PM) and nitrogen oxides (NO_x) emissions are the significant advantages of operating with dual fuel.Consequently, fuels used in the present work are renewable and can generate power for different applications. Hydrogen being gaseous fuel acts as an alternative and shows fascinating use along with diesel to operate the engines with lower emissions. Such engines can also be operated either by injection or induction on compression of gaseous fuels for combustion by initiating with the pilot amount of biodiesel. Present work highlights the experimental investigation conducted on dual fuel mode operation of diesel engine using Neem Oil Methyl Ester (NeOME) and producer gas with enriched hydrogen gas combination. Experiments were performed at four different manifold hydrogen gas injection timings of TDC, 5°aTDC, 10°aTDC and 15°aTDC and three injection durations of 30°CA, 60°CA, and 90°CA. Compared to baseline operation, improvement in engine performance was evaluated in combustion and its emission characteristics. Current experimental investigations revealed that the 10°aTDC hydrogen manifold injection with 60°CA injection duration showed better performance. The BTE of diesel + PG and NeOME + PG operation was found to be 28% and 23%, respectively, and the emissions level were reduced to 25.4%, 14.6%, 54.6%, and 26.8% for CO, HC, smoke, and NO_x, respectively.     

生物制气-柴油双燃料发动机燃烧及排放分析

采用气化炉热解气化各种农林废弃的生物质,得到可燃生物制气。将柴油机改制成双燃料发动机,用生物制气作为主要燃料,由柴油引燃。测量生物制气-柴油双燃料发动机在最大扭矩转速时的气缸压力及废气排放,分析燃烧特性及对排放物生成的影响,并对比分析柴油机与双燃料发动机的差别。     

柴油机燃用LPG的高原特性实验研究

在高原环境条件下,针对柴油机燃用LPG的经济性,动力性和排放排性进行了研究,柴油机掺烧LPG后,在一定的掺烧比下,动力性有所提高,经济性有所改善,碳煤排放降低幅放较大,但发动机振动和大,噪声和排温升高,试验结果为在高原地区推广应用PLG／柴油双燃料发动机提供了依据。     

Effect of hythane enrichment on performance,emission and combustion characteristics of an ci engine

Although compression ignition engines have high torque output and thermal efficiency, they emit lots of NO_x and smoke emissions. Moreover, total number and percentage of compression ignition engine powered vehicles in road vehicles have been increasing recent years which is called as dieselisation in EEA term reports. Dieselisation is really hazardous for human life and environment. Therefore, some governments in Europe take action to forbid using diesel engine powered vehicles in city centers. Hydrogen and methane mixture which is named as hythane can be an alternative to restrict this negative situation. For this reason, 90% methane and 10% hydrogen gas mixture was used as additional fuel in diesel engine. According to obtained results, smoke emission was decreased 95.44% at the rate of 50% gaseous fuel at 2100 rpm engine speed. However, increase of THC, CO and NO_x emissions with hythane addition weren't prevented. Using hythane in conventional diesel engines as dual operation mode will be solution to diminish dieselisation problem in near feature.