船用柴油机NOx排放控制技术

本文简要介绍了船用柴油机的排放法规和现阶段国内外船用柴油机降低NOx排放的最新技术及其应用情况,并对满足未来超低排放法规的船用柴油机NOx排放控制技术进行了展望。     

切向进气船用脱硫塔流场的数值模拟研究

针对船用脱硫塔塔内喷头数量的选择和喷射角度的问题,以船用六缸两冲程G128ZC型柴油机额定工况下排放的废气为研究对象,通过建立切向进气船用海水脱硫塔模型,采用Gambit软件对该模型进行网格划分,使用Fluent软件对该塔塔内气的流湍流强度和流速进行计算。仿真计算结果表明:切向进气船用海水脱硫塔塔内气流的流速和湍流强度呈规律性分布,整体塔内气流流向为旋转上升,塔内的同一水平面内的气流流速越靠近塔壁流速越大,反之越小;塔内中下部湍流强度高,上部湍流强度低,湍流强度沿着塔高方向逐渐减弱。该仿真结果为船用脱硫塔塔内喷淋方向的布置和喷头数量的选择提供了理论依据。     

第一万台“淄柴”牌柴油机出厂

日前,淄博柴油机厂隆重举行仪式,庆祝第一万台“淄柴”牌柴油机出厂。淄博柴油机厂始建于1970年,1977年正式投产,最初年产只有2台柴油机,总功率558千瓦,2005年达到年产柴油机2576台、总功率近200万千瓦,已经形成年产柴油机总功率350万千瓦的生产能力。产品由建厂时一个系列20多个品种发展到目前6大系列300多个品种。“淄柴”牌柴油机已由原来单一用于渔机市场拓展到整个船机市场；由单一的轻油机市场拓展到重油机市场；由单一的水上市场拓展到陆机市场。另外,在其他市场领域如生物质气体机组、煤气机组、油田用机、带水泵用机、泥浆泵用机、军队用机等均有突破。主导产品在国内同等功率船用柴油机市场占有率达35％以上。同时还出口越南、泰国、尼日利亚和科威特等20多个国家或地区,在国内、国际都有较高的知名度。     

MC系列船用大功率低速柴油机近十年发展历程

MANB&W公司研发的MC系列大功率低速柴油机自问世以来已在市场上使用了二十多年,在造船及航运界享有口碑。该系列产品自问世以来经历一系列的改进和升级发展过程,目前最新型的Mark9型机已经开始问鼎市场。本文对该系列船用低速柴油机的发展过程作了简要回顾,希望能对我国的船用柴油机研发有所参考或启发。     

柴油机缸套穴蚀及其预防

缸套穴蚀是柴油机常见的失效形式。本文首先探讨了缸套穴蚀的形成机理,其次从缸体系统设计、冷却系统设计及柴油机工况等三个方面分析了影响穴蚀的因素,最后从重负荷冷却液选用、冷却系统维护方面提出缸套穴蚀的预防措施。     

MAN-B&W MC/MC-C系列船用低速柴油机的发展及改进

为满足世界船舶市场的需求,MAN-B&W公司自80年代推出MC系列(后又发展成:MC/IVIC-C系列)船用大功率柴油机,当初仅以600mm缸径为代表,发展到今日,已成为从260 mm～980 mm缸径不同缸数的全系列,并仍在继续扩大,结构和性能更加完善合理,可为各类船舶提供最佳匹配的船用主机.文章着重介绍MC/MC-C系列船用低速柴油机的设计发展及改进情况.     

MAN-B&W MC/MC-C系列船用低速柴油机的发展及改进

为满足世界船舶市场的需求,MAN-B&W公司自80年代推出MC系列(后又发展成:MC/IVIC-C系列)船用大功率柴油机,当初仅以600mm缸径为代表,发展到今日,已成为从260 mm～980 mm缸径不同缸数的全系列,并仍在继续扩大,结构和性能更加完善合理,可为各类船舶提供最佳匹配的船用主机.文章着重介绍MC/MC-C系列船用低速柴油机的设计发展及改进情况.     

双燃烧系统加热炉的设计及应用

针对油田老站改造时场地限制因素及油田被加热介质工况不稳定、单台加热炉在运行过程中功率变化超出燃烧器调节能力范围、多重介质同时或不同时加热而出现的大跨度负荷变化等条件限制或加热炉工况因素,设计一种大跨度功率调节直通式真空加热炉,应用表明此种设计不仅能满足多介质工况需求,弥补了现有加热炉的不足,减少设备、场地投资,同时还能适应油田站内被加热介质逐年变化等工况,有效降低设备维护投入成本。     

内河船用柴油机冷却水系统节能探讨

内河船用柴油机在工作时,其燃油经济性能、动力性能和环境性能直接受到冷却系统性能的好坏的限制。本文对内河船用柴油机冷却水系统节能进行了探讨,提出了对冷却水温度进行恒温控制必将成为冷却水系统设计的重点。     

高海拔隧道施工劳动强度与供氧浓度关系研究北大核心CSCD

为研究高海拔隧道施工人员供氧浓度问题,文章通过骑行试验得到了不同人员在海拔高度为590~4000 m,氧气浓度为20.9%~29%,骑行功率为0、50 W、75 W、100 W工况下的生理指标,得到测试对象的劳动强度指数,分析研究得到以下结论:(1)在同一海拔高度、相同劳动强度工况下,提升环境氧气浓度,可以显著降低人员劳动强度指数;(2)劳动强度指数的减少与氧气浓度的增加并不是线性关系,当环境氧气浓度超过25%时,劳动强度指数的降低程度有限;(3)拟合得到了劳动负荷为100 W且氧气浓度为20.9%~25%时施工人员的劳动强度指数与海拔高度及供氧浓度的关系式。     

The role of nano additives for biodiesel and diesel blended transportation fuels

The energy crisis is due to two reasons, one is the rapid increase in worldwide population and the other is changing living style of human beings. The fossil fuel is also a major contributor to add the harmful pollutants into the atmosphere. Fuel modifications play a major role in increasing engine efficiency and reducing emissions. In the present investigation focused on fuel modifications in diesel engine. Initially the single cylinder diesel engine was operated with 20MEOM, 40MEOM, 60MEOM, 8MEOM and 100MEOM without additives with diesel at different loads at constant rated speed. From the experimental study proved that 20MEOM is the best fuel ratio compared to other blends. In second phase based upon first phase results the engine was operated 20MEOM blended fuel with adding 50 ppm copper oxide nano additives with diesel using solgel process. From the results, the brake thermal efficiency was 2.19% improved compared than 20MEOM blend without additive at full load condition. Emissions of HC, CO and smoke were considerably reduced. The present analysis reveals that the biofuel from mahua oil with nano additives is quite suitable as an alternate fuel for diesel engine.     

Operational profiles of ships in Norwegian waters: An activity-based approach to assess the benefits of hybrid and electric propulsion

Various regulations are imposed on shipping to increase energy efficiency and reduce environmental impacts. Alternative fuels and power systems are among the solutions for compliance with these regulations. The power system of a ship may not operate optimally because of the diversity of the operational profile during its lifetime. This article uses an activity-based approach and big data from the Automatic Identification System (AIS) to study the operational profiles of eight ship types operating in Norwegian waters around mainland Norway in 2016. The aim is to identify ship types that can benefit from electric and hybrid propulsion through analysis of their operational profiles. Close to shore, the operational profiles of various ship types are similar, and all ships spend a great proportion of their time with lower loads. As the distance from shore increases, the operational profiles of various ship types follow distinct trends. Among the considered ship types, reefers spend more operational time close to the diesel engine design condition. On the other hand, offshore and passenger ships show the most dynamic operational profiles and spend a large percentage of their operational time with a partial load, away from diesel engine design conditions. Such ships can benefit from hybridisation, diesel-electric propulsion, and other electric concepts, such as batteries and fuel cells. Another option is to downsize diesel engines for better operation while fuel cells and batteries supply peak and partial loads. Operational profiles are plotted and details of the approach are presented in the article.     

Developing link-based particle number emission models for diesel transit buses using engine and vehicle parameters

To better assess health impacts from diesel transportation sources, particle number emissions can be modeled on a road network using traffic operating parameters. In this work, real-time particle number emissions rates from two diesel transit buses were aggregated to the roadway link-level and modeled using engine parameters and then vehicle parameters. Modern statistical methods were used to identify appropriate predictor variables in the presence of multicollinearity, and controlled for correlated emission measurements made on the same day and testing route. Factor analysis helped to reduce the number of potential engine parameters to engine load, engine speed, and exhaust temperature. These parameters were incorporated in a linear mixed model that was shown to explain the variation attributable to link-characteristics. Vehicle specific power and speed were identified as two surrogate vehicle travel variables that can be used in the absence of engine parameters, although with a loss in predictive power compared to the engine parameter model. If vehicle speed is the only operating input available, including road grades in the model can significantly improve particle number emission estimates even for links with mild grade. Although the data used are specific to the buses tested, the approach can be applied to modeling emissions from other vehicle models with different engine types, exhaust systems, and engine retrofit technologies.     

Experimental investigation of evaporation rate and exhaust emissions of diesel engine fuelled with cotton seed methyl ester and its blend with petro-diesel

An experimental study to measure the evaporation rates, engine performance and emission characteristics of cotton seed biodiesel (cotton seed oil methyl ester) and its blends in different volumetric proportions with diesel is presented. The thermo-physical properties of all the fuel blends have been measured and presented. Evaporation rates of neat cotton seed biodiesel, neat diesel and their bends have been measured under slow convective environment of air flowing with a constant temperature. Evaporation constants have been determined by using the droplet regression rate data. The neat fuels and fuel blends have been utilized in a test engine with different load conditions to evaluate the performance, combustion and emission characteristics of the fuels. The specific fuel consumption values of the two blends, viz. B25 and B75 are found to be same. At the highest load, B0 records the lowest CO volume followed by B100. From the observed evaporation, performance and emissions characteristics, it is suggested that a blend of B50 and B75 can be optimally used in standard diesel engine settings.     

电力推进技术在渡船中的应用

近年来,国家陆续出台了关于长江生态保护的相关文件。随着电力推进技术在节能减排方面的优势显现,常规动力渡船存在的问题显而易见,如较长传动轴增加了能量损耗,降低了能源效率;柴油机的响应较慢,影响船舶的机动性;柴油机的燃烧不充分导致燃油的过多消耗,以及柴油机直驱渡船的动力推进装置占据了机舱的大部分空间。本文结合电力推进渡船的应用情况,针对上述常规推进渡船的缺点,对船舶动力系统进行了改进,采用全回转电力推进取代原先柴油机直驱,电站采用高压共轨电喷式柴油机带动发电机发电,经整流实现直流组网后,统一为全船提供动力和日常用电。     

Characteristics of gaseous and particulate pollutants exhaust from logistics transportation vehicle on real-world conditions

On-road vehicle tests of three heavy duty diesel trucks were conducted by a portable emission measurement system (PEMS) in Chengdu, China. SEMTECH-ECOSTAR provided by Sensors Inc. was employed to detect gaseous emissions and MI2, an emissions measuring instrument powered by the Pegasor Particulate Sensor (PPS) was used to detect particulate emissions during the tests. The impacts of speed, acceleration and engine load on emissions were analyzed. The average nitrogen oxides (NOx) emission factors of the heavy duty diesel truck (HDDT), medium-duty diesel truck (MDDT), light duty diesel truck (LDDT) were 7.29, 5.29 and 5.53 g/km. The particulate emission factors were 0.60, 0.30 and 0.14 g/km respectively, higher than the similar reported in the previous studies. Both gaseous and particulate emission exhibit significant correlations with the change in vehicle speed, acceleration and power demand. The highest emission was generally in high VSPs and higher loads. High engine load caused by aggressive driving was the main factor of high emissions for the vehicles on real-world conditions.     

Effect on direct injection naturally aspirated diesel engine characteristics fuelled by pine oil,ceiba pentandra methyl ester compared with diesel

This paper explores the experimental investigation of the performance, emission and combustion characteristics of bio fuels from ceiba pentandra methyl ester (CPME), ceiba pentandra methyl ester-pine oil blends (CPMEP) and pine oil and the results are compared with diesel. In ceiba pentandra seed oil the CPME yield is 92% by using transesterification process with the optimum conditions of 560 rpm, reaction time 58 min, catalyst concentration 13 g and methanol amount 500 ml. The viscosity of CPME is high when compare with diesel. So the low viscosity of pine oil is blended with CPME and it can be directly used in diesel engine without any modification. At different loads the Pine oil, CPME and CPMEP blends were used in direct injection naturally aspirated compression ignition engine. The outcomes exhibited that at full load conditions for CPME and CPMEP blends increased brake specific fuel consumption, and decreased brake thermal efficiency, CO, HC emissions. NOx emissions decreased and smoke emissions are increased on CPME and CPMEP blends, expect B25 blend compared with diesel. The combustion analysis like the heat release rate, peak cylinder pressure, cumulative heat release rate and ignition delay for CPME, CPMEP blends slightly lower and combustion duration higher than diesel and pine oil. At the Same engine operating condition, the engine fuelled with pine oil the values of brake thermal efficiency 4.79%, peak cylinder pressure, heat release rate, cumulative heat release rate and ignition delay are increased. Brake specific fuel consumption, CO, HC, and smoke were 9.46%, 16.66%, 14.89% and 8.33% decreased. However, the NOx emission is 8.29% higher than that of diesel. Experimental fuels up to B50 (50% pine oil and 50% CPME) blends have proved good potential for future energy is needed.     

HCCI内燃机工作过程控制方式研究及技术前景展望

本文介绍了均质压燃(HCCI)内燃机的工作过程及技术特点,重点阐述了对其工作过程的控制方式,并对其未来发展前景进行了展望,同时点明了其当前面临的技术挑战。HCCI内燃机是近年来广受关注的一类新型内燃机,其兼具传统汽油机及柴油机的技术优势,尽管其目前依然存在一定的技术挑战,但随着相关技术的不断完善与优化,其必将得以广泛应用。     

基于冷却液温度的发动机性能优化研究

在台架上对不同冷却液温度下发动机性能测试的基础上,分析了温度对发动机基本性能影响。基于转速和负荷,给出最优目标温度Map图并进行整车油耗仿真计算。结果表明,冷却液温度对发动机低速工况下动力性和经济性有较大影响;与装配蜡式节温器的整车相比,整车采用优化后的水温Map将会使综合油耗降低1%左右。     

Using a chassis dynamometer to determine the influencing factors for the emissions of Euro VI vehicles

In order to explore the influence of different factors on the emissions of heavy diesel vehicles, a chassis dynamometer was used to test and analyze a Euro VI standard heavy-duty diesel vehicle under different load, fuel, driving conditions, and resistance conditions. The full load condition was found to increase NOx emissions by about 0.107 g/km (30%) and the particulate matter (PM) by 0.003 g/km (18%) compared to the empty load condition. Compared with the China V diesel, the NOx emissions of the Beijing VI diesel were reduced by 0.065 g/km (18%), and PM decreased by 0.004 g/km (25%). The HC, CO, PM, and NOx emissions measured during the Chinese World Harmonized Transient Cycle (C-WHTC) were 0.002 g/km (27%), 0.0005 g/km (14%), 0.0024 g/km (15%), and 0.092 g/km (25%) higher, respectively, than those measured during the European Transient Cycle (ETC). The HC, CO, PM, and NOx emissions measured by using the test resistance were 0.002 g/km (28%), 0.001 g/km (25%), 0.003 g/km (18.7%), and 0.09 g/km (25.7%) higher, respectively, than those calculated with the recommended formula.