柴油机

Methanol can pyrolyze and generate hydrogen when it is heated by the exhaust of diesel engine(temperature range between 400℃and 600℃). Then let the hydrogen generated from methanol go into cylinder with the air directly. By this means, we hopefully increase the rate of economizing oil of emulsified fuel in diesel engine.

利用柴油机排烟(温度一般在400～600℃)余热加热甲醇热分解制氢，并在线通入到柴油机进气道入口，有望实现柴油机燃用乳化油时节油率的提高。

On generator working condition,e xperimental cycles are made on NO x em is sion from a 4135G diesel engine by changin g injection timing and compression ratio , based on technical code on emission of m a rine diesel engine drawm up by Internati onal Maritime Organization.

在保证柴油机的经济性前提下，寻找降低柴油机NOx 排放率的途径，根据IMO《船用柴油发动机氮氧化物释放控制技术规则》推荐的试验程序，对一台 4 135G柴油机在发电机工况下进行改变喷油正时和压缩比的试验研究。

The instantaneous angular speed based on the flexible body model underdiffierent faults simulated is calculated, which shows the rule of the instantaneousangular speed fluctuation ratio due to the underpower of a single cylinder. Therefore,the maximum power fluctuation ratio of the instantaneous angular speed is proposed to diagnose the fault of single cylinders underpower.

2进行了基于柔性体模型的柴油机瞬时转速故障仿真计算，揭示了柴油机单缸功率不足的瞬时转速波动规律，提出了采用最大瞬时转速波动率作功峰值的无量纲参数诊断柴油机单缸功率不足故障，并定位到故障缸的瞬时转速诊断新方法，并在船舶柴油机上得到应用。

Based on the numeric monitoring and diagnosis system for 6L16/24 typemarine diesel engine, the instantaneous angular speed and the cylinder pressure areapplied to the monitoring and diagnosing of the marine diesel engine through theartificial faults experiments in laboratory. The experiments results show that theintegrated motheds both the instantaneous angular speed and the cylinder pressurecan effectively diagnose the underpower fault of single cylinder, and detects whichcylinder occurs.

5利用船舶柴油机数字化监测诊断系统平台，进行了船舶柴油机瞬时转速和示功图法监测诊断的故障模拟试验研究，研究结果表明：瞬时转速法和示功图法可有效诊断柴油机单缸功率不足的故障，并可定位到故障缸。

In this paper Ⅰ successfully applied these methods to fault diagnosis, and presenting some new innovative machinery fault diagnosis method; First Ⅰ present a new gear wornout fault diagnosis method, this method use the vibration signal's time-frequency attribute and instantaneous phase undulation to accurately detect gear's fault, and by comparing with the traditional frequency domain analysis method, this method reveals that many nonlinear and nonstationary characteristic exist in gear's vibration, this tell us that if we use frequency domain analysis method without pay attention to the signal's characteristic, we could get wrong diagnostic result; Then Ⅰ present a new bearing fault diagnosis method, this method use ATVFD and Hilbert transform to do envelop demodulation,Ⅰ analyze the envelop with time-frequency method and find out that this method is more accurate then traditional method.Ⅰ also explain that the modulation of the fault to the carrier wave may also be non-stationary and nonlinear; Finally Ⅰ present a cylinder pressure measurement method of diesel engine by means of vibration, cylinder pressure is an important parameter of diesel engine fault diagnosis, the pressure measuring is simplified a lot by this method,Ⅰ also use the ATVFD and time-frequency analysis to realize it.

本文中将上述理论方法成功地应用到故障诊断中去，提出了几点创新性的诊断方法；提出了一种齿轮磨损故障诊断的新方法，该方法利用振动信号能量的时频域分布特征与瞬时相位波动特征可以进行精确的齿轮故障诊断，并通过与传统的频域诊断方法的比较，揭示出齿轮振动中存在的明显的非线性与非平稳特征，说明了不加选择地利用频域分析方法进行齿轮故障诊断很可能会得到错误的诊断结果；提出了一种轴承故障诊断的新方法，该方法利用ATVFD分解与Hilbert变换进行包络解调，并对解调得到的包络信号进行时频域分析，可以实现更加准确轴承故障诊断，说明了故障对载波信号的调制往往也是非平稳与非线性的；提出了一种利用振动信号进行柴油机汽缸内压力检测的新方法，柴油机汽缸压力的变化是柴油机故障诊断的重要参数，利用振动方法可大大简化汽缸压力的检测过程，该方法也是综合利用ATVFD分解与时频域分析方法实现的。

In order to study the intake air flow characteristics in four-valve diesel engines, in this dissertation hot-wire anemometer and PIV twodimension instantaneous measuring technique are used. Extensive experimental study on two intake valve exit flow fields and longitudinal section flow field in cylinder are performed for different type of diesel engines. Great researching progress have been made on the interaction between two intake ports, and the formation process of in-cylinder swirl and flow field structure of cross and longitudinal section for four valve diesel engines. These results are presented in China for the first time and without such kind of research work reported abroad as detailed and deepgoing as this dissertation. The author designs and makes a set of hot wire measuring velocity device to measure the velocity distribution around the intake valve annulus and the cross section flow field in cylinder.

为了研究四气门柴油机进气过程中气体流动的变化规律，本文利用热线测速和PIV二维瞬态测速技术，对四气门柴油机两进气门出口全圆周流速场和缸内横、纵剖面的气体流动流场进行了大量的试验研究，在四气门柴油机两进气道之间相互影响的变化规律，缸内涡流的形成过程及缸内横、纵剖面流场结构等方面取得了重大的研究进展，这一研究工作在国内尚属首次，在国外也未见有如此全面、深入的研究报道。

The goals can be arrived by turbocharging, electronic control and and structure optimization. In order to investigate the influence of various techniques on the performance of diesel engine, the engine cycle simulation is one of the most efficient method to improve the performance of truck diesel engine and determine the optimum design.

多样化的涡轮增压、电子控制以及结构优化措施为实现以上目标创造了条件，为了有效地研究各种技术措施对柴油机性能的影响，为重型车用柴油机性能的改善和提高确定最优方案，必须充分利用柴油机循环模拟这一有效的手段。

The laboratory based closed cycle diesel test rig was built based on the previous CO_2 experimental research.

在前期CO2 实验研究的基础上，完成了闭式循环柴油机氧气配比、开闭式转换和可视化状态监控系统的设计与实现，在实验室中建立了闭式循环柴油机及其监控系统实验台架，并成功实现了柴油机的闭式循环。

YMD is the only engine maker in the world who has licenses for three different brands of low speed marine engines with the License Agreement in early 2007 with Mitsubishi on manufacturing of UE series of engines, and this strengthens YMD's flexibility to meet different customers' demands. Capacity expansion actions during past years with huge investment improves greatly productivity, YMD is now capable of producing 150 sets of low speed marine engines totaling 1.5 million BHP per year.

为此，公司一方面引进了日本三菱重工的 UE 低速柴油机制造技术，成为世界上唯一一家拥有三种低速柴油机专利许可证的主机制造商，大大增强了满足市场需要的能力；另一方面，投入巨资进行扩能改造，生产能力成倍地增长，目前已经具备年产150万马力低速柴油机的能力。

When left when the test-drive after repair in shop main engine is adding this ship to 540r/min, supercharger occurrence asthma brace up phenomenon, rotate speed lifts slightly again, noise shakes very big, smoke evacuation temperature is normal, hair of on the high side of temperature of air inlet duct is very hot, as good as of smoke evacuation smoke constant, supercharger rotor rotate speed and the rotate speed of right leader supercharger that work normally comparative. 2 breakdown analyse this model diesel engine supercharger breathes heavily brace up the reason has the following sides. Bearing of 1 supercharger rotor damages, bring about on the low side of supercharger rotor rotate speed or wave motion, make inadequacy of compressor part air feed and diesel engine and its demand do not match, bring about air current not to stabilize generation to breathe heavily brace up. 2 diesel engine offers oil, match gas to time forbid, match gas, draw well time and disorder, bring about supercharger to breathe heavily brace up. 3 supercharger nozzle jams, cause smoke evacuation not free, circumfluence of exhaust stroke waste gas, enter jackknife of new energy of life with the below one stroke that take energy of life, produce air current to hit generation to breathe heavily brace up. Canal of 4 smoke evacuation jams, smoke evacuation not free, bring about waste gas circumfluence, hit generation of new energy of life to breathe heavily brace up. 5 jams into gas mouth, enter gas inadequacy, generation breathes heavily brace up. 3 trouble removal are based on above analysis, adopt the following measure to remove trouble.

该舰在厂修后试车时左主机在加至540r/min时，增压器出现喘振现象，转速再略升高，声响震动很大，排烟温度正常，进气管温度偏高发烫，排烟烟色无异常，增压器转子转速和正常工作的右主机增压器转速相当。2故障分析该型柴油机增压器喘振的原因有以下几个方面。1增压器转子轴承损坏，导致增压器转子转速偏低或波动，使得压气机部分供气不足和柴油机及其需求不匹配，导致气流不稳定产生喘振。2柴油机供油、配气定时不准，配气、发火定时紊乱，导致增压器喘振。3增压器喷嘴堵塞，导致排烟不畅，排气冲程废气回流，和下一进气冲程进新气重叠，发生气流冲撞产生喘振。4排烟管堵塞，排烟不畅，导致废气回流，冲撞新气产生喘振。5进气口堵塞，进气不足，产生喘振。3故障排除基于以上分析，采取以下办法排除故障。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。