电控单体泵柴油机燃油喷射控制策略

电控单体泵由电控泵喷嘴发展而来,由于在电控泵与喷油器之间加入了高压油管,使电控单元从发出喷油信号到燃油喷入汽缸的时间延迟加长.针对该特点,以及考虑到程序计算时间、电磁阀响应特性等因素对喷油正时的影响,设计了喷油正时控制策略.试验结果表明,电控单元可按喷油正时控制策略准确地、柔性地控制喷油正时和喷油量.     

智能型柴油机消防泵组在消防给水系统中的应用

介绍了智能型柴油机消防泵组与电动消防泵组在消防给水系统中的联动作用，阐述了柴油机消防泵组的基本工作原理。在分析其自动控制的基础上给出了自动控制的硬件线路设计和PLC程序设计。     

柴油机电子油门传感器的线性优化

理论上分析了影响电子油门传感部件线性度的关键因素：电子油门传感部件径向磁场磁感应强度.通过对影响电子油门传感部件径向磁场磁感应强度的各个因素：初级线圈长度和半径、偏心圆盘偏心矩和半径、初级激励电压的分析.提出了各个因素优化来提高电子油门传感部件线性度的方法,得出了电子油门传感部件最佳线性度的性能参数.并对与其匹配的信号调理电路进行了最佳线性优化.依据柴油机电子油门控制系统模拟实验装置平台,对优化后的油门传感器进行了柴油机加减负荷模拟实验,并进行了误差分析.结果表明：柴油机电子油门控制系统的动态响应达0.23 s,线性度为0.38%,完全满足电子油门控制系统正常工作的要求.     

Research on effects of key influencing factors upon fuel injection characteristics of the combination electronic unit pump for diesel engines

A numerical model of the combination electronic unit pump (CEUP) fuel injection system was developed in AMESim environment. The effects of five key influencing factors, including cam profile velocity, plunger diameter, length of high pressure fuel pipe, inner diameter of high pressure fuel pipe and nozzle flow rate on injection characteristic parameters, were analyzed by using the developed numerical model. On the basis, a correlation analysis between the influencing factors and injection characteristics was performed by using the design of experiments (DoE) method, and the influences of these factors were quantized accordingly. Relevant results show that both the single influencing factor and the interaction among these factors correlates with the injection characteristics, and the correlation represents a complex law with the cam rotational speed. The effect of plunger diameter on the injection pressure, cycle fuel injection quantity and injection duration is the most obvious, especially at a cam rotational speed of 500 r/min and the correlation coefficient is up to 0.82. The length of high-pressure pipe (HP pipe) has the most obvious influence on the coefficient of fuel feeding at cam rotational speed of 500 r/min and 800 r/min, and the correlation coefficient is negative. Overall, the independent influence of the factors is more significant than the combined influence of various factors. The CEUP fuel injection system is a complicated multi-input multi-output (MIMO) nonlinear system in fact.     

Correlation analysis of factors influencing the electronic unit pump cycle fuel injection quantity under overall operating conditions for diesel engines

Electronic unit pump (EUP) can satisfy both diesel engine emission legislation and fuel economy by improving injection pressure and numerical control. Fluctuations in cycle fuel injection quantity (CFIQ) of EUP determine the coherence and stability of the EUP fuel injection system. The EUP simulation model is developed in the AMESim environment. The method for the simulation experiment is designed in the MODDE environment using the design of experiments method. The results of the simulation reveal the variation laws of correlation between parameters with interaction or no interaction under overall operating conditions of diesel engines. In addition, the results also show the EUP system is a complex nonlinear system. Under overall operating conditions, all the characteristic parameters, such as fuel supply pressure, cam profile velocity, control valve lift, injector opening pressure, injector needle lift, and injector flow coefficient, have significant correlation with CFIQ. The interacting first-order factors exhibit the most significant correlation with CFIQ. The self-interacting second-order factors have significant secondary correlation with CFIQ.     

虚拟设计在柴油机VE型分配泵中的应用

介绍了VE型分配泵的结构特点和性能优势,探讨了虚拟设计在VE型分配泵中的应用.对VE泵传动系统中各关键零部件(传动主轴、十字块、端面凸轮等)进行了应力响应分析和模态分析,并对研究结果进行了验证.介绍了虚拟装配技术的必要性,给出了VE型分配泵虚拟装配的爆炸效果图.找出了VE型分配泵各传动件断裂的原因.为结构设计的改进提供了依据,在企业的实际应用中取得了理想的效果.     

Application of a genetic-fuzzy system to diesel engine pressure modeling

The aim of this work was to build an empirical–analytical model for diesel engine operation and control. The engine that was used was fueled by biofuels or diesel oil and the measurements of cylinder pressure were conducted on a test bench. The engine model was built by means of a proposed genetic-fuzzy system. This model allows simulation of cylinder pressure for each allowable crankshaft speed with accuracy required in practical technical applications.     

电控单体泵循环喷油量测量方法及分析

基于先进的 EFS 瞬时喷油量测量仪,采用位移法分别对电控单体泵不同转速工况进行循环喷油量的精确测量。依据循环喷油量及喷油压力的试验数据,得到了电控单体泵喷油量不一致性变化规律以及不同转速下的主要影响因素。分析结果表明,在最大扭矩工况,各单体泵循环喷油量不一致性最低,而启动工况和最大功率工况的不一致性较高。     

Experimental research on pressure fluctuation and vibration in a mixed flow pump

To study the pressure fluctuation and vibration in mixed flow pumps, we chose a mixed flow pump with specific speed of 436.1 to measure. The time domains and frequency domain at each monitoring point on diffuser and outlet elbow were analyzed, as well as the vibration frequency domain characteristics at the impeller outlet and near the motor. The results show that the peak value of pressure fluctuation peak decreased gradually with the increase of flow rate. The pressure fluctuation of each monitoring point had periodicity, and the frequency domain dominated by blade passing frequency and multiple shaft frequency. The vibration frequency of each monitoring point occurred at shaft frequency and its multiple shaft frequency. The dominant frequency and the second frequency were distributed in shaft frequency and double shaft frequency.     

Leakage and rotordynamic analysis of a high pressure floating ring seal in the turbo pump unit of a liquid rocket engine

The floating ring seal is often used in an oxidizer and a fuel pump of the turbo pump unit in the liquid rocket engine because the floating ring seal has the ability to minimize clearance without rubbing phenomenon. For the analysis of performance and vibration characteristics of the turbo pump unit with floating ring seals, the exact prediction of the lock-up position of the floating ring is essential to evaluate the leakage and rotordynamic coefficients from the floating ring seal. The governing equations, which are based on the ‘bulk-flow model’, are derived from extending the eccentric annular plain seal analysis. The solution procedure is developed by using the Fast Fourier Transform Method of Nelson and Nguyen. The results of lock-up position, attitude angle of the floating ring, leakage flow rate, and rotordynamic coefficients are presented with operating conditions and geometric parameters of the floating ring seal for an example case.     

基于YC2105小型农用柴油机电控调速器控制策略研究

随着柴油机技术的发展,柴油机电子调速的控制研究越来越多,本文针对YC2105柴油机调速器在农用发动机上应用的缺陷即难以实现较为复杂的调节规律和控制功能,无法满足降低油耗、提高调节精度、减少有害排放等要求,研究了YC2105柴油机电控调速器控制策略,设计了柴油机基本喷油量、起动喷油量及怠速条件三种情况下的电控调速器控制策略。为下步实现控制模型的建立打下良好基础。     

Investigation on characteristics of pressure fluctuation in a centrifugal pump with clearance flow

Journal of Mechanical Science and Technology - Clearance flow has great impact on pressure fluctuation of centrifugal pumps. Numerical calculations are performed to study the pressure fluctuation...     

CUMMINS柴油发动机电子调速器及控制系统故障诊断

系统介绍CUMMINS柴油发动机电子调速器及控制系统的工作原理、调整方法和故障诊断技术,有利于准确、快速地排除该类机型的故障.     

Determination of diesel sprays characteristics in real engine in-cylinder air density and pressure conditions

The present paper centers on the establishment of a quantified relationship between the macroscopic visual parameters of a Diesel spray and its most influential factors. The factors considered are the ambient gas density, as an external condition relative to the injection system, and nozzle hole diameter and injection pressure as internal ones. The main purpose of this work is to validate and extend the different correlations available in the literature to the present state of the Diesel engine, i.e. high injection pressure, small nozzle holes, severe cavitating conditions, etc. Five mono-orifice, axi-symmetrical nozzles with different diameters have been studied in two different test rigs from which one can reproduce solely the real engine in-cylinder air density, and the other, both the density and the pressure. A parametric study was carried out and it enabled the spray tip penetration to be expressed as a function of nozzle hole diameter, injection pressure and environment gas density. The temporal synchronization of the penetration and injection rate data revealed a possible explanation for the discontinuity observed as well by other authors in the spray’s penetration law. The experimental results obtained from both test rigs have shown good agreement with the theoretical analysis. There have been observed small but consistent differences between the two test rigs regarding the spray penetration and cone angle, and thus an analysis of the possible causes for these differences has also been included.     

Advanced lubricants for diesel engine particulate control

Diesel exhaust particulates contain an organic fraction than can be attributed to the engine lubricant. This lubricant fraction varies from a mass fraction of 15% to over 50%, depending on the engine and the operating conditions. This paper addresses the issue of developing novel lubricants that have a lower contribution to diesel particulate. In this work, an analytical technique (TGA/DTA) was developed to measure rapidly the lubricant contribution to diesel particulate. Two apparatus were constructed to simulate the interactions between carbonaceous soot and lubricant products under a variety of test conditions. The combination of simulation apparatus and analytical technique guided the development of lubricants with reduced contribution to particulate. Several formulated lubricants were developed, based on concepts of lower volatility and better oxidative and thermal stability. Initial testing of these lubricants in the simulation apparatus indicated several candidates with reduced interaction with diesel particulate soot.     

Weak compressibility effects on the pressure fluctuation at RSI in a highspeed centrifugal pump

Journal of Mechanical Science and Technology - This study presents large eddy simulation of high-speed centrifugal pump at approximate quarter load (0.23 Qd) and design load (Qd) conditions. Two...     

高压共轨式喷油系统对柴油机排放的影响

本文在介绍共轨式喷油系统的特点后,从放热率,燃烧噪场、喷油压力等方面来着重阐述高压共轨式喷没系统改善柴油机性能各个机理和措施。     

Dynamic performances analysis and optimization of novel high-speed electromagnetic actuator for electronic fuel injection system of diesel engine

Journal of Mechanical Science and Technology - High-speed electromagnetic actuator (HEA) is the key component of Electronic fuel injection system (EFIS) of diesel engine, its dynamic performances...     

柴油机的排放、测量标准与柴油机未来发展

1 内燃机行业的形势 在我国，整个柴油机行业存在着能源、环保和加入世贸组织后的竞争三种危机： 1）连续3年我国石油开采量在1.6亿吨以上，但储备量很有限，从1993年开始我国是纯石油进口国，而石油产品的50%用于内燃机行业。 2）去年322个城市的大气质量达到或超过3类指标，全球污染最严重的15个城市，中国占7个。环保要求对柴油机行业来讲，将愈来愈严格。尤其对于车用发动机来说是致命的。 3）加入世贸组织后，随着关税的减让和全球采购的进行，低价优势就不再存在，再加上1997年后农民的购买力没有实质性增加，所以柴油机行业的竞争非…