共查询到20条相似文献,搜索用时 93 毫秒
1.
2.
3.
为了提升整车在单轴底盘测功机上进行油耗试验时的测试精度,基于整车利用底盘测功机进行非驱动轮惯量测试,采用测试值代替经验值,并对油耗结果进行对比,验证在油耗测试时采用非驱动论惯量测试值加载对结果的影响。首先利用底盘测功机测试整车的车轮惯量,得到整车在底盘测功机上的加载质量;其次对整车的万有特性进行测试,得到整车在发动机不同转速、不同功率下的燃料消耗量;再通过整车万有特性对不同车轮惯量(经验值和测试值)加载下的中国重型商用车测试工况(CHTC)油耗和中国-世界重型商用车瞬态循环工况(C-WTVC)油耗进行仿真校核,最终得到车轮惯量测试值和经验值的油耗差值,其结果表明,使用车轮惯量测试值时,能够有效提高单轴底盘测功机的测试精度。 相似文献
4.
基于多因素神经网络模型的柴油机NO_x排放预测及试验研究 总被引:2,自引:0,他引:2
以发动机转速、进气量、循环油量、发动机出水温度、中冷后进气温度、进气湿度、排气背压、柴油温度作为输入,NO_x排放质量流量为输出,优化隐层节点和迭代次数,并经过样本训练,构建了NO_x排放预测模型。结合台架试验数据,验证了模型的泛化能力,其预测值与试验值间误差小于1.5%。在此基础上,利用模型进一步分析了试验因素的重要度和试验控制性。结果表明:发动机转速、循环油耗、中冷后进气温度、排气背压对柴油机NO_x排放的影响相对较高;进气湿度控制范围过宽,对NO_x排放测试结果影响高于其他因素。 相似文献
5.
6.
7.
排气损失能量是发动机热损失的主要形式,在进行整车能量分布表征时需要对其进行量化测试。基于此测试原理构建转毂测试系统,并进行了系统的实车测试试验。对试验数据分析表明,排气能量损失与瞬时油耗强相关。基于试验数据建立了排气能量损失与瞬时油耗的关系曲线。论文研究为发动机排气能量损失测试与表征提供了有效手段。 相似文献
8.
9.
10.
发动机油耗过高是指汽车的百公里油耗超过标定值。影响发动机油耗的因素很多,涉及发动机、底盘、车身等多方面,本文着重讨论发动机技术状况对燃油消耗的影响。 相似文献
11.
高压共轨柴油机高海拔性能仿真研究 总被引:2,自引:0,他引:2
采用GT-Power软件建立了高压共轨柴油机工作过程模型,研究了等油量和等空燃比条件下柴油机性能随高原环境条件的变化规律。结果表明:等油量下,柴油机扭矩和燃油消耗率在海拔3 000 m以内中高转速范围基本保持不变;在海拔4 000 m以上标定转速下增压器超速,海拔5 000 m,900 r/min时发动机因空燃比过低而无法运行。等空燃比下,同0 m海拔相比,海拔5 000 m不同转速下发动机燃油消耗率平均增加7.2%,扭矩平均下降近40%,动力性下降严重。等油量或等空燃比方法不符合我国高原实际情况,需要建立新的柴油机性能高海拔修正或预测方法。 相似文献
12.
A. J. Torregrosa A. Broatch P. Olmeda C. Romero 《International Journal of Automotive Technology》2008,9(4):447-458
One of the major goals of engine designers is the reduction of fuel consumption and pollutant emissions while keeping or even
improving engine performance. In recent years, different technical issues have been investigated and incorporated into internal
combustion engines in order to fulfill these requirements. Most are related to the combustion process since it is responsible
for both fuel consumption and pollutant emissions. Additionally, the most critical operating points for an engine are both
the starting and the warming up periods (the time the engine takes to reach its nominal temperature, generally between 80°C
and 90°C), since at these points fuel consumption and pollutant emissions are larger than at any other points. Thus, reducing
the warm-up period can be crucial to fulfill new demands and regulations. This period depends strongly on the engine cooling
system and the different strategies used to control and regulate coolant flow and temperature. In the present work, the influences
of different engine cooling system configurations on the warm-up period of a Diesel engine are studied. The first part of
the work focuses on the modeling of a baseline engine cooling system and the tests performed to adjust and validate the model.
Once the model was validated, different modifications of the engine coolant system were simulated. From the modelled results,
the most favourable condition was selected in order to check on the test bench the reduction achieved in engine warm-up time
and to quantify the benefits obtained in terms of engine fuel consumption and pollutant emissions under the New European Driving
Cycle (NEDC). The results show that one of the selected configurations reduced the warm-up period by approximately 159 s when
compared with the baseline configuration. As a consequence, important reductions in fuel consumption and pollutant emissions
(HC and CO) were obtained.
On doctoral leave from Universidad Technológica de Pereira (Colombia) 相似文献
13.
S. S. Merola P. Sementa C. Tornatore B. M. Vaglieco 《International Journal of Automotive Technology》2009,10(5):545-553
A low-cost solution based on fuel injection strategies was investigated to optimize the combustion process in a boosted port
fuel injection spark ignition (PFI SI) engine. The goal was to reduce the fuel consumption and pollutant emissions while maintaining
performance. The effect of fuel injection was analyzed for the closed and open valve conditions, and the multiple injection
strategies (MIS) based on double and triple fuel injection in the open-valve condition. The tests were performed on an optical
accessible single-cylinder PFI SI engine equipped with an external boost device. The engine was operated at full load and
with a stoichiometric ratio equivalent to that of commercial gasolines. Optical techniques based on 2D-digital imaging were
used to follow the flame propagation from the flame kernel to late combustion phase. In particular, the diffusion-controlled
flames near the valves and cylinder walls, due to fuel deposition, were studied. In these conditions, the presence of soot
was measured by two-color pyrometry, and correlated with engine parameters and exhaust emissions measured by conventional
methods. The open valve fuel injection strategies demonstrated better combustion process efficiency than the closed ones.
They provided very low soot levels in the combustion chamber and engine exhaust, and a reduction in specific fuel consumption.
The multiple injection strategies proved to be the best solution in terms of performance, soot concentration, and fuel consumption. 相似文献
14.
15.
16.
机械损失对现代车用发动机燃料经济性的影响很大,轿车发动机因为其经常在很小的负荷率下运行,故障低机构损失的对改善其油耗和排放将更大的效果,分析了轿车发动机基本参数,零部件设计等对摩擦损失的影响,提出了降低其机械损失的若干措施。 相似文献
17.
通过TVDI燃烧方法的采用,与此前的第一代发动机相比,油耗进一步明显地降低了,在欧洲EU测试循环中节油9%。 相似文献
18.
EGR对车用柴油机性能影响的试验研究 总被引:2,自引:0,他引:2
结合某废气涡轮增压和高压共轨小型4缸柴油机国Ⅳ排放达标工作,进行了计算机在线实时控制EGR对柴油机性能影响的试验研究,通过试验分析了EGR对NOx、烟度、排气温度、燃油消耗率的影响规律,并对EGR率与喷油提前角的匹配作了进一步的研究。结果表明,为降低柴油机NOx排放,不同工况应采取不同的EGR率;烟度、排气温度、燃油消耗率均随着EGR率的增加而增大;EGR率和喷油提前角应实现良好的匹配,才能保证NOx排放和燃油消耗率都能达到要求,其中小EGR率匹配小喷油提前角,大EGR率匹配大喷油提前角。 相似文献
19.
单轴并联式混合动力系统(Parallel Hybrid Electric Vehicle,PHEV)包括电池、驱动电机、发动机、自动变速器等多个关键部件。各部件效率特性存在相互耦合的关系,要实现系统整体效率最优,需要辨明影响系统效率的控制参数,并对系统整体效率最优的控制参数进行优化。以装备无级变速器(Continuously Variable Transmission,CVT)的PHEV为研究对象,首先对系统各关键部件的效率特性进行分析,建立各关键部件效率模型,明确各部件效率与控制参数、状态参数之间的关系。在此基础上,对发动机单独驱动模式下动力传递路径中不同部件的效率耦合关系进行分析,推导出系统燃油消耗量与动力系统各状态参数、控制参数之间的函数关系。根据分析结果,选取车辆需求功率及车速为状态参数,变速器速比及发动机转矩为控制参数,以系统燃油消耗量最小为目标建立优化目标函数和约束条件,对系统优化问题进行定义。根据优化问题的特点,设计基于模拟退火的优化算法对优化问题进行求解,获取系统燃油消耗率最小时变速器目标速比和发动机目标转矩随状态参数的变化关系。建立系统仿真模型对所述优化算法进行仿真分析,并搭建混合动力试验台对优化结果进行试验验证。结果表明:无级变速器效率对系统整体效率影响较大,采用优化控制规律使发动机效率有所降低,但无级变速器效率升高更大,系统整体效率升高;在功率需求一定的循环工况下,优化控制算法比传统上仅以发动机效率最高为目标的控制算法节油1%~2%。 相似文献
20.
甲醇作为一种代用燃料,可以与汽油混合使用,人们对使用低比例甲醇燃料发动机的性能十分关注。文章对加入M15甲醇汽油和加入93#汽油的发动机分别经过300 h台架强化试验,测试发动机功率、扭矩及油耗率。强化后,2种燃料的动力性能相近,但M15甲醇汽油的燃料消耗量比汽油高出9%。在汽油发动机中,直接使用M15甲醇汽油,除发动机燃料经济性变差外其他基本无变化。 相似文献