非道路小型柴油机降低机油耗的研究

以186FA柴油机为样机,通过对曲轴箱负压、配缸间隙、气缸孔实际工作圆柱度及活塞环参数改进试验和分析,得出了小型单缸柴油机减少机油消耗量降低颗粒排放的技术措施和机理。经控制参数优化,186FA柴油机机油耗由2.31g/(kW·h)降至0.65g/(kW·h),柴油机颗粒排放降低至0.43g/(kW·h)。加装氧化催化剂后处理,柴油机达到了美国EPA Tire4排放限值和安全要求。     

满足单缸柴油机国-Ⅱ排放的技术难题与对策

结合单缸柴油机产品特点,分析了国内外小功率段柴油机排放法规标准的限值变化,针对单缸柴油机结构特点、行业现状及技术问题,阐明了低排放高性能单缸柴油机的研发难度和需解决的问题,给出了单缸柴油机优化性能及降低排放的技术路线和对策.分析表明:通过柴油机喷油系统、换气系统与燃烧室结构优化设计和匹配,特别是提高单缸柴油机用喷油系统的性能,优化燃烧过程的机内净化措施能满足GB19756、GB20891的排放限值的要求.     

三功能单缸喷油泵的研制

<正> 1 概述近几年来,我国以柴油机作动力的小型运输车辆得到了突飞猛进的发展。众所周知,作小型运输车辆、工程机械及拖拉机动力用的单缸柴油机必须有油量限制及扭矩校正装置。这类装置,可以装在柴油机的齿轮箱盖上,这已在国内一些单缸柴油机上试用,但用这种油量限制及扭矩校正装置,在柴油机出厂试验时,调整较麻烦,且往往难     

生物柴油在非道路用柴油机上的实验研究

本文以非道路用186FA柴油机为研究对象,进行了生物柴油和0#轻质柴油经济性、排放性能对比实验。实验结果表明,186FA柴油机不需要改装就可以使用生物柴油。柴油机燃用两种燃油时,相同的功率条件下,生物柴油热效率提高。燃用生物柴油有利于降低CO、HC、颗粒,但是NOx排放会增加。生物柴油在非道路用柴油机上有广阔的应用前景。     

扭矩校正器的设计和计算

本文导出了中小功率单缸柴油机扭矩校正器的校正行程、校正力、校正弹簧刚度和预紧力、起动加浓行程等计算公式。给出了在结构设计上实现起动加浓行程的必要条件。分析了获得较为理想的扭矩特性曲线的方法和实践的结果。     

降低单缸直喷柴油机排放的思路及有效措施

随着<非道路移动机械用柴油机排放限值及测量方法(中国Ⅰ、Ⅱ阶段)>节能减排标准的实施,我们对柴油机燃油喷射系统进行了优化改进,验证了一些能有效降低单缸直喷柴油机排放指标的措施,有利于达到国家标准要求.本文从柴油机燃油喷射系统的喷油泵、高压油管、喷油器的改进入手,对降低排放的措施进行原理分析和验证.     

S195、S1100型柴油机油量限制和扭矩校正的研究

本式主要以S195型柴油机为例,论述了改善单缸小功率柴油机扭矩特性的途径。从影响柴油机扭矩特性的因素考虑,分析了S 195型柴油机用单体喷油泵的速度特性。文中还分析了机械式校正器的工作原理和结构,介绍了校正参数的计算方法。     

新一代立式单缸高速（3000r／min）DL193型柴油机（三等奖）

DL193型单缸柴油机是由佛山市顺德德力柴油机有限公司运用多项自有专利技术开发的，填补国内空白的一种新机型，是国内单缸水冷柴油机行业率先完成了标定转速为3000r/min的第二代单缸柴油机。其最显著特点是性能指标、排放指标均达到并超过国家第二代（新一代）单缸柴油机技术要求。满足比现行国家标准高一级的限制要求。     

单缸柴油机电控化的开发和试验研究

绿色环保、节能降耗是国内外各行业特别是发动机制造行业的重大课题,也是摆在内燃机技术工作者面前的历史使命.目前发动机的电控化是国内外降低排放的重要技术手段.单缸柴油机电控化的应用可提升单缸柴油机技术档次,进而满足节能降耗和绿色环保的要求.     

单缸柴油机电控单缸泵的设计制造与匹配试验

为了满足日益严格的排放法规的要求,提出了单缸柴油机实现电控化的设想,介绍了电控单缸泵的设计目标、方案、工作原理,阐述了电控单缸泵的主要零部件泵体、柱塞、控制阀部件和衔铁的设计特点,电控单缸泵与立式单缸柴油机的匹配试验显示,相关试验数据均达到了新一代高效柴油机标准的要求,尤其是烟度值由原1.8~3.1 FSU降低到0.4~1.0 FSU,燃油耗指标平均降低了4%左右,说明柴油机与电控燃油喷射系统匹配良好。     

Engine and winter road test performances of used cooking oil originated biodiesel

Biodiesel is a renewable and environmentally friendly alternative fuel that can be used in Diesel engines with little or no modification. Low cost feedstocks, such as waste oils, used cooking oil and animal fats, are important for low cost biodiesel production. The objective of this study was to investigate the engine performance and the road performance of biodiesel fuel originated from used cooking oil in a Renault Mégane automobile and four stroke, four cylinder, F9Q732 code and 75 kW Renault Mégane Diesel engine in winter conditions for 7500 km road tests in urban and long distance traffic. The results were compared to those of No. 2 Diesel fuel. The results indicated that the torque and brake power output obtained during the used cooking oil originated biodiesel application were 3–5% less then those of No. 2 Diesel fuel. The engine exhaust gas temperature at each engine speed of biodiesel was less than that of No. 2 Diesel fuel. The injection pressures of both fuels were similar. Higher values of exhaust pressures were found for No. 2 Diesel fuel at each engine speed. As a result of the No. 2 Diesel fuel application, the engine injectors were normally carbonized. After the first period, as a result of winter conditions and insufficient combustion, carbonization of the injectors was observed with biodiesel usage. As a result of the second period, since the viscosity of the biodiesel was decreased, the injectors were observed to be cleaner. Also, no carbonization was observed on the surface of the cylinders and piston heads. The catalytic converter was plugged because of the viscosity in the first period. At the second period, no problem was observed with the catalytic converter.     

CNG-diesel engine performance and exhaust emission analysis with the aid of artificial neural network

This study investigates the use of artificial neural network (ANN) modelling to predict brake power, torque, break specific fuel consumption (BSFC), and exhaust emissions of a diesel engine modified to operate with a combination of both compressed natural gas CNG and diesel fuels. A single cylinder, four-stroke diesel engine was modified for the present work and was operated at different engine loads and speeds. The experimental results reveal that the mixtures of CNG and diesel fuel provided better engine performance and improved the emission characteristics compared with the pure diesel fuel. For the ANN modelling, the standard back-propagation algorithm was found to be the optimum choice for training the model. A multi-layer perception network was used for non-linear mapping between the input and output parameters. It was found that the ANN model is able to predict the engine performance and exhaust emissions with a correlation coefficient of 0.9884, 0.9838, 0.95707, and 0.9934 for the engine torque, BSFC, NO_x and exhaust temperature, respectively.     

Advantages of the direct injection of both diesel and hydrogen in dual fuel H2ICE

The turbocharged Diesel engine is the most efficient engine now in production for transport applications with full load brake engine thermal efficiencies up to 40-45% and reduced penalties in brake engine thermal efficiencies reducing the load. The secrets of the turbocharged Diesel engine performances are the high compression ratio and the lean bulk combustion mostly diffusion controlled in addition to the better use of the exhaust energy. Despite these advantages and the further complications of hydrogen in terms of abnormal combustion phenomena and displacement effect, the most part of the dual fuel Diesel-hydrogen engines has been developed so far injecting hydrogen in the intake manifold or in the intake port, and then injecting the Diesel fuel in the cylinder to ignite there a homogeneous mixture. This paper shows how a latest production common-rail Diesel engine could be modified replacing the Diesel injector by a double injector as those proposed by Westport since more than two decades for CNG first and then for CNG and hydrogen to provide much better performances. A model is first developed and validated versus extensive high quality dynamometer data for the Diesel engine only covering with almost 200 points the load and speed range. This model replaces the multiple injection strategy with a single equivalent injection for the purposes of the brake efficiency results still providing satisfactory accuracy. The model is then used to simulate the dual fuel operation with a pilot Diesel followed by a main hydrogen injection replacing the Diesel fuel with the hydrogen fuel and using the same parameters for start and duration of the equivalent injection at same percentage load and speed. While the top load air-to-fuel ratio of the Diesel is a lean 1.55, the top air-to-fuel ratio of the hydrogen is assumed to be a stoichiometric 1. Within the validity of these assumptions it is shown that the novel engine has better than Diesel fuel conversion efficiencies and higher than Diesel power outputs. These results clearly indicate the development of the direct injection system as the key factor where to focus research and development for this kind of engines.     

80缸径单缸柴油机直喷燃烧系统的开发研究

本文介绍了80缸径直喷式单缸柴油机燃烧系统中的燃烧室、进气道、喷油泵、喷油器以及高压油管结构参数的优化设计方案，并通过试验说明该燃烧系统具有燃油耗低、低温起动性能好、排放性能优的特点，有实用推广价值。     

可变喷油速率的超高压共轨系统喷射控制研究

通过AMESim软件建立了喷油速率可调的超高压共轨系统仿真模型,分析了相同喷油量条件下喷油率的变化特点。采用GT-Power软件建立单缸柴油机模型,将不同喷油率导入柴油机的燃烧计算模型,研究了不同喷油率对柴油机缸内压力、缸内温度、放热率、NO_x排放、碳烟排放及输出转矩和油耗率的影响。仿真结果表明:靴形喷油速率匹配合适的喷油提前角可优化柴油机的综合性能。搭建了超高压共轨柴油机台架,开展了不同喷油速率的喷射控制试验,结果表明:与相同油量条件下的高压共轨喷射相比,柴油机实施变喷油速率超高压喷射可获得更优异的动力性和燃油经济性,动力输出提高了5%,燃油消耗量下降了6%,碳烟排放降低,但NO_x排放升高。     

船用低速二冲程柴油机应对低硫燃油的设计发展

重点介绍了MAN柴油机公司对船用低速柴油机所做的改进设计,以解决船舶柴油机燃用低硫燃油所带来的问题,具体包括:燃烧室(活塞环、活塞头、气缸衬)和气缸润滑的改进设计。     

Performance of direct-injection off-road diesel engine on rapeseed oil

This article presents the comparative bench testing results of a naturally aspirated, four stroke, four cylinder, water cooled, direct injection Diesel engine operating on Diesel fuel and cold pressed rapeseed oil. The purpose of this research is to study rapeseed oil flow through the fuelling system, the effect of oil as renewable fuel on a high speed Diesel engine performance efficiency and injector coking under various loading conditions.Test results show that when fuelling a fully loaded engine with rapeseed oil, the brake specific fuel consumption at the maximum torque and rated power is correspondingly higher by 12.2 and 12.8% than that for Diesel fuel. However, the brake thermal efficiency of both fuels does not differ greatly and its maximum values remain equal to 0.37–0.38 for Diesel fuel and 0.38–0.39 for rapeseed oil. The smoke opacity at a fully opened throttle for rapeseed oil is lower by about 27–35%, however, at the easy loads its characteristics can be affected by white coloured vapours.Oil heating to the temperature of 60 °C diminishes its viscosity to 19.5 mm² s⁻¹ ensuring a smooth oil flow through the fuel filter and reducing the brake specific energy consumption at light loads by 11.7–7.4%. Further heating to the temperature of 90 °C offers no advantages in terms of performance. Special tests conducted with modified fuel injection pump revealed that coking of the injector nozzles depends on the engine performance mode. The first and second injector nozzles that operated on pure oil were more coated by carbonaceous deposits than control injector nozzles that operated simultaneously on Diesel fuel.     

2缸高压共轨柴油机增压器性能匹配与研究

针对一款2缸高压共轨4气门增压柴油机,基于2缸柴油机进、排气压力波动的特殊性,研究了不同发火顺序的发动机排气对增压器匹配的影响,选择了360°CA的发火顺序,分析了2缸柴油机增压器效率的波动及泵气损失的特点。兼顾乘用车对柴油机高低速性能的要求,设计了2种方案的增压器进行分析和匹配试验,提出了增压器的改进优化技术措施并进行了优化试验。试验结果表明:柴油机中低速性能得到了改善,低速扭矩增加了8N.m,燃油消耗率降低了12g/(kW.h),柴油机的各项性能指标满足设计目标,排放达到欧Ⅳ标准。     

Influence of fuel additives on performance of direct-injection Diesel engine and exhaust emissions when operating on shale oil

The article presents the comparative bench testing results of a naturally aspirated four stroke, four cylinder, water cooled, direct injection Diesel engine when running on shale oil that has been treated with multi-functional fuel additives. The purpose of the research is to evaluate the effectiveness of the fuel additives Marisol FT (Sweden) and SO-2E (Estonia) as well as to verify their ability to increase energy conversion and reduce brake specific fuel consumption, contamination and smoke opacity of the exhausts when fuelling the Diesel engine with shale oil.Test results show that application of these additives could be a very efficient means to improve Diesel engine performance on shale oil, especially when operating at the light load range. The brake specific fuel consumption at light loads and speeds of 1400–2000 min⁻¹ reduces by 18.3–11.0% due to the application of the Marisol FT. The additive SO-2E proves to produce nearly the same effect.The total NO_x emission from the fully loaded Diesel engine fuelled with the treated shale oil reduces by 29.1% (SO-2E) and 23.0% (Marisol FT). It is important that the lower NO_x is obtained due to reducing both harmful pollutants, NO and NO₂. The CO emission at rated power increases by 16.3% (SO-2E) and 48.0% (Marisol FT), whereas the smoke opacity of the exhausts increases by 35% and over 2 times, respectively. The effect of the fuel additives on the HC emission seems to be complicated and ambiguous.