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<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 相似文献
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为了探究可变进气系统对船用柴油机性能的影响,在一台配备进气可变配气和进气旁通阀的船用中速柴油机上开展试验研究。分别在可变配气机构处于强米勒正时和弱米勒正时,进气旁通阀处于开启和关闭状态下开展船用柴油机螺旋桨特性试验。试验结果表明:采用弱米勒正时可降低燃油消耗率,但是最高燃烧压力和NOx比排放增加,燃油消耗率降低幅度随负荷升高而减小,最高燃烧压力和NOx比排放增加幅度随负荷升高而增加,弱米勒正时对低负荷优化效果更明显。受到最高燃烧压力限制,高负荷必须采用强米勒正时。弱米勒正时角度从20°增加到30°,燃油消耗率基本不变,最高燃烧压力和NOx比排放进一步增加,对于试验柴油机而言,20° 弱米勒正时配置更优。开启进气旁通阀可以提高中低负荷增压压力,降低燃油消耗率、排温和烟度。在超低负荷及高负荷时开启进气旁通阀效果与中低负荷相反。在25%及50%负荷下应用可变进气技术,燃油消耗率分别降低6.0%和2.9%、烟度分别降低61.6%和59.7%。合理的可变进气系统控制策略可有效优化船用柴油机性能。 相似文献
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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NOx排放明显低于纯柴油模式,NOx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。 相似文献
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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NOx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NOx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。 相似文献
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液化天然气(Liquefied Ntural Gsa a,LNG)是一种低碳洁净燃料,是实现航运业碳减排的过渡性关键燃料。甲烷是一种强温室效应气体,甲烷泄漏是LNG双燃料发动机面临的一个难题。通过优化双燃料机操作管理与科学维护来减少温室气体的排放,探索零排放发动机创新之路。结合多年双燃料发动机管理经验,可以进一步发掘商用船用双燃料发动机全生命周期使用价值,降低发动机日常运营过程中的碳排放,探索在当前双碳能源背景下的新型低碳运维管理方法。详细分析了瓦锡兰6L20DF型双燃料柴油机的特点及日常操作管理中的注意事项,从轮机管理角度给出双燃料机长期保持在燃气模式下高效运转及减少甲烷泄漏量的维护措施,通过提高船用双燃料发动机低碳运维管理水平确保船舶安全。 相似文献
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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 相似文献
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《能源学会志》2020,93(3):953-961
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 SOx, 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. 相似文献
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Makame Mbarawa 《Biomass & bioenergy》2010,34(11):1555-1561
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 NOx emissions were increased remarkably when the engine was fuelled with the 50% CSO–diesel blended fuel. 相似文献
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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 NOx emissions. Hence, HES is found beneficial in reducing harmful emissions at low and mid loads. 相似文献
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Chandra Bhushan Kumar D.B. Lata Dhaneshwar Mahto 《International Journal of Hydrogen Energy》2021,46(14):9595-9612
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 NOx 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 NOx 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. 相似文献
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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 NOx 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. 相似文献
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《International Journal of Hydrogen Energy》2022,47(62):25913-25928
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 (NOx) 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 NOx, respectively. 相似文献
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柴油机燃用LPG的高原特性实验研究 总被引:1,自引:0,他引:1
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。 相似文献
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《International Journal of Hydrogen Energy》2019,44(5):3208-3220
Although compression ignition engines have high torque output and thermal efficiency, they emit lots of NOx 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 NOx 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. 相似文献