期刊文献+
共找到747篇文章
< 1 2 38 >
每页显示 20 50 100
Research on Spray, Combustion and Emission Characteristics for DI Diesel Engine 被引量:1
1
作者 葛蕴珊 张世鹰 +1 位作者 周磊 张付军 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期17-21,共5页
To improve the combustion chamber shape that can decrease the directed injection (DI) diesel emission, the theories of DI diesel spray, combustion and pollutant formation model are analysed and implemented based on ... To improve the combustion chamber shape that can decrease the directed injection (DI) diesel emission, the theories of DI diesel spray, combustion and pollutant formation model are analysed and implemented based on the CFD code FIRE. Results show that the chamber with contracting orifice can get stronger squish swirl intensity. The results of the verification studies show a good accordance with the measurements and reveal that the individual processes of spray, evolution, combustion and pollutant formation are well captured in FIRE. Finally, based on the analyzing and comparing of the calculation results of different chambers, a combustion chamber of contracting orifice geometry with lower emission is proposed. 展开更多
关键词 three-dimensional CFD calculation DI diesel engine spray COMBUSTION EMISSION
在线阅读 下载PDF
Multidimensional modeling of Dimethyl Ether(DME) spray combustion in DI diesel engine 被引量:1
2
作者 文华 刘永长 +1 位作者 魏明锐 张煜盛 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第4期276-282,共7页
In the present study a modified CFD code KIVA3V was used to simulate the spray combustion in a small DI diesel engine fueled with DME. The improved spray models consider more spray phenomena such as cavitation flow in... In the present study a modified CFD code KIVA3V was used to simulate the spray combustion in a small DI diesel engine fueled with DME. The improved spray models consider more spray phenomena such as cavitation flow in nozzle hole, jet atomization, droplet second breakup and spray wall interaction. Otherwise, a reduced DME reaction mechanism is implemented in the combustion model, and a new turbulent combustion model?Partial Stirred Reactor (PaSR) model is selected to simulate the spray combustion process, the effects of turbulent mixing on the reaction rate are considered. The results of engine modeling based on those models agreed well with the experimental measurements. Study of temperature fields variation and particle traces in the combustion chamber revealed that the engine combustion system originally used for diesel fuel must be optimized for DME. 展开更多
关键词 Dimethyl ether (DME) diesel engine spray combustion
在线阅读 下载PDF
Dynamic Characteristic Investigation on the Fuel Pressure of Diesel Engines Electronic In-line Pump System
3
作者 刘友 袁志国 +1 位作者 范立云 田丙奇 《Journal of Marine Science and Application》 2010年第4期410-418,共9页
The electronic in-line pump (EIP) is a complex system consisting of mechanical, hydraulic, and electromagnetic parts. Experimental study showed that the fuel pressure of the plunger and the fuel drainage of the pressu... The electronic in-line pump (EIP) is a complex system consisting of mechanical, hydraulic, and electromagnetic parts. Experimental study showed that the fuel pressure of the plunger and the fuel drainage of the pressure system after fuel injection could result in fuel pressure fluctuation in the low pressure system. Such fluctuation exhibited pulsating cycle fluctuation as the amplitude rose with the increase of the injection pulse width. The time domain analysis found that the pressure time history curve and injection cylinders corresponded with a one-to-one relationship. By frequency domain analysis, the result was that with the increase of the working cylinder number, the high frequency amplitude gradually increased and the basic frequency amplitude gradually decreased. The conclusion was that through wavelet transformation, the low pressure signal simultaneously moved towards low frequency as the high frequency of the wavelet transformation signal with the working cylinder number increased. Lastly, by using the numerical model, the study investigated the simulation research concerning the relationship of the fluctuation dynamic characteristic in the low pressure system and the fuel injection characteristic of the high pressure system, completing the conclusions obtained by the experimental study. 展开更多
关键词 EIP Marine diesel engine Pressure dynamic characteristic FFT
在线阅读 下载PDF
Study on Spray Characteristics of Dimethyl Carbonate Blended Fuel in IC Engines
4
作者 Fu Wei Zhou Kun +5 位作者 Liu Junya Xie Hongxi Li Yayun Lu Lei Bao Jihu Cheng Yunlang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2021年第4期29-36,共8页
The spray characteristics of the blended fuel composed of biodiesel and dimethyl carbonate were compared with those of biodiesel and diesel.The macroscopic spray characteristic parameters including spray tip penetrati... The spray characteristics of the blended fuel composed of biodiesel and dimethyl carbonate were compared with those of biodiesel and diesel.The macroscopic spray characteristic parameters including spray tip penetration,maximum spray width,average spray cone angle,and peak tip velocity were used to evaluate the spray characteristics of the blended fuel.The results showed that the spray tip penetration of blended fuel was lower than that of biodiesel,while the spray cone angle and maximum spray width of blended fuel were both larger than that of biodiesel.On the basis of the Hiroyasu and Arai mathematical model combined with the actual working conditions of this experiment,including physical parameters such as the viscosity and density of the fuel,a correct model of spray penetration was established,and the experimental results were compared. 展开更多
关键词 BIOdiesel dimethyl carbonate diesel spray characteristics mathematical model
在线阅读 下载PDF
Simulation Studies of Diesel Engine Combustion Characteristics with Oxygen Enriched Air
5
作者 Heng Wang Weijun Liu 《Journal of Power and Energy Engineering》 2015年第8期15-23,共9页
Based on a six-cylinder direct injection diesel engine, the engine operating condition was simulated by application AVL-FIRE software coupling the n-heptane reduced mechanism containing polycyclic aromatic hydrocarbon... Based on a six-cylinder direct injection diesel engine, the engine operating condition was simulated by application AVL-FIRE software coupling the n-heptane reduced mechanism containing polycyclic aromatic hydrocarbon (PAH) formation. The simulation and its verification test were both carried out under the maximum torque point. Then, the oxygen enriched combustion was simulated on the model, and the simulated condition was oxygen volume fraction from 21% to 30%. The simulation results show that, the oxygen enrichment (from 21% to 30%) increases the peak cylinder pressure of 3.32%, advances the start of combustion of 1.6 deg and rises the peak of average temperature in cylinder and wall heat flux. Among them, at the condition of 24% O2, the change of the results is the most significant. Benzene (A1) is one of the precursors of soot generated, the analysis of its impress-cuts of the mass distribution field in cylinder shows that, the increase of oxygen concentration can significantly inhibit the formation of benzene. But the oxygen enrichment makes the combustion more sufficient, cased a rise in the cylinder temperature, an extension in high temperature area, and an increment in the NOx emission. 展开更多
关键词 diesel engine Numerical SIMULATION OXYGEN Enriched COMBUSTION COMBUSTION characteristic
在线阅读 下载PDF
Simulation of quasi-dimensional model for diesel engine working process 被引量:1
6
作者 齐鲲鹏 冯立岩 +2 位作者 冷先银 田江平 隆武强 《Journal of Central South University》 SCIE EI CAS 2010年第4期868-872,共5页
In order to satisfy the demand of validity and real time operating performance of diesel engine model used in hardware-in-the-loop simulation system,a simplified quasi-dimensional model for diesel engine working proce... In order to satisfy the demand of validity and real time operating performance of diesel engine model used in hardware-in-the-loop simulation system,a simplified quasi-dimensional model for diesel engine working process was proposed,which was based on the phase-divided spray mixing model.The software MATLAB/Simulink was utilized to simulate diesel engine performance parameters.The comparisons between calculated results and experimental data show that the relative error of power and brake specific fuel consumption is less than 2.8%,and the relative error of nitric oxide and soot emissions is less than 9.1%.At the same time,the average computational time for simulation of one working process with the new model is 36 s,which presents good real time operating performance of the model.The simulation results also indicate that the nozzle flow coefficient has great influence on the prediction precision of performance parameters in diesel engine simulation model. 展开更多
关键词 diesel engine phase-divided spray mixing model quasi-dimensional model MATLAB/SIMULINK prediction precision
在线阅读 下载PDF
Simulation and Experimental Research on Fuel Spray Characteristics of a Self-pressurized Injector
7
作者 JI Haocheng LIU Rui +1 位作者 LI Jing ZHAI Buyun 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第1期66-78,共13页
As a miniaturized direct injection(DI)solution,a self-pressurized injector is of great significance for small aviation piston engines,such as spark-ignited two-stroke heavy-fuel engines.The spray characteristics of DI... As a miniaturized direct injection(DI)solution,a self-pressurized injector is of great significance for small aviation piston engines,such as spark-ignited two-stroke heavy-fuel engines.The spray characteristics of DI injectors are an important application prerequisite.In this paper,the computational fluid dynamics(CFD)software AVL Fire is employed to study the spray characteristics.Two types of spray models are established based on the Han Sheet model and the KH-RT model,and simulation works are carried out according to two types of spray tests in the literature.The comparison results show that in the constant volume bomb test,the spray patterns obtained by simulation under the two sets of environmental pressures are similar to those in the experiment,and the simulation spray using the KH-RT model can fit the spray contraction of the near nozzle field and the vortex of the far nozzle field better.In the tube test,the spray patterns obtained by simulation under the five sets of flow velocity are similar to those in the experiment,and the simulation spray using the KH-RT model can fit the spray expansion and the vortex of the far nozzle field better.The RP-3 kerosene spray characteristics of the self-pressurized injector are also experimentally studied,and the results demonstrate that due to the higher viscosity of kerosene,the spray shrinks more easily,resulting in a smaller spray cone angle and larger penetration.Therefore,changes in environmental pressure have greater impact on the kerosene spray pattern. 展开更多
关键词 direct injection spray characteristics piston engine self-pressurized injector
在线阅读 下载PDF
Effect of Intake Conditions and Nozzle Geometry on Spray Characteristics of Group-Hole Nozzle
8
作者 Jianfeng Pan Jinpeng Hua +1 位作者 Jiaqi Yao Abiodun Oluwaleke Ojo 《Energy Engineering》 EI 2023年第7期1541-1562,共22页
The group-hole nozzle concept is proposed to meet the requirement of nozzle hole minimization and reduce the negative impact of poor spatial spray distributions.However,there are limited researches on the effects of i... The group-hole nozzle concept is proposed to meet the requirement of nozzle hole minimization and reduce the negative impact of poor spatial spray distributions.However,there are limited researches on the effects of intake conditions and nozzle geometry on spray characteristics of the group-hole nozzle.Therefore,in this study,an accurate spray model coupled with the internal cavitating flow was established and computational fluid dynamics(CFD)simulations were done to study the effects of intake conditions and nozzle geometry on spray characteristics of the group-hole nozzle.Experimental data obtained using high-speed digital camera on the high-pressure common rail injection system was used to validate the numerical model.Effects of intake conditions(injection pressure and temperature)and nozzle geometry(orifice entrance curvature radius and nozzle length)on the flow and spray characteristics of the group-hole nozzle were studied numerically.The differences in Sauter mean diameter(SMD),penetration length and fuel evaporation mass between single-hole nozzle and group-hole nozzle under different nozzle geometry were also discussed.It was found that the atomization performance of the group-hole nozzle was better than that of the single-hole nozzle under same intake conditions,and the atomization effect of the short nozzle was better than that of the long nozzle.With increase in the orifice entrance curvature radius,the average velocity and turbulent kinetic energy of the fuel increased,which was conducive to improving the injection rate and flow coefficient of the nozzle.Meanwhile,the penetration length and SMD value rose,while evaporation mass dropped.When the ratio of the orifice entrance curvature radius(R)to the diameter of injection hole(D)was 0.12,the spray characteristics reached a constant state due to elimination of cavitation.Conclusions were made based on these.This study is expected to be a guide for the design of the group-hole nozzle. 展开更多
关键词 diesel spray characteristics group-hole nozzle coupling model
在线阅读 下载PDF
Experimental investigation on diesel engine's waste heat capacity under mapping characteristics 被引量:2
9
作者 TIAN Hua ZHANG ChengYu +1 位作者 LI XiaoNing SHU GeQun 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第1期9-18,共10页
Waste heat recovery for internal combustion engine(ICE)has been considered as an important strategy to improve efficiency and promote fuel economy,thus alleviating the problems of energy shortage and environmental pol... Waste heat recovery for internal combustion engine(ICE)has been considered as an important strategy to improve efficiency and promote fuel economy,thus alleviating the problems of energy shortage and environmental pollution.This paper investigates the characteristics of various kinds of waste heat energy,namely,waste heat in exhaust,cooling water and charge air,over the engine’s whole operating region.Based on the energy balance experiments,the energy distribution of a conventional heavy-duty diesel engine is obtained under mapping characteristics.According to exergy analysis,the energy recovery potential for waste heat is studied as well.The experimental results indicate that exhaust energy increases with engine speed and load,while cooling water energy is more sensitive to load,especially at low and middle speed.Charge air energy,on the other hand,mainly counts on speed rather than load.Exhaust energy possesses the highest recovery potential in terms of both quantity and quality.Through waste heat recovery,a dramatic improvement in engine efficiency is achievable,actually,the maximum value can amount to 60%or even more. 展开更多
关键词 waste heat recovery mapping characteristics diesel engine energy balance exergy analysis
原文传递
Study of Diesel Spray Particle Velocity Field Using a Particle Image Velocimetry Setup
10
作者 郝利君 刘福水 +1 位作者 刘玉林 孙济美 《Journal of Beijing Institute of Technology》 EI CAS 1999年第2期90-95,共6页
Aim To investigate the spray particle velocity and its distribution characteristics. Methods\ A set of PIV (particle image velocimetry) system was developed and used to observe and analyze the spray particle velocity... Aim To investigate the spray particle velocity and its distribution characteristics. Methods\ A set of PIV (particle image velocimetry) system was developed and used to observe and analyze the spray particle velocity field. Results and Conclusion\ Double exposure image of the spray particle within the region of 10-50 mm from the nozzle tip was recorded and analyzed by the IBAS2000 analysis system. Some characteristics of the spray particle velocity and its distribution were obtained. 展开更多
关键词 PIV (particle image velocimetry) diesel engine spray velocity characteristics
在线阅读 下载PDF
Vibration-based feature extraction of determining dynamic characteristic for engine block low vibration design 被引量:2
11
作者 杜宪峰 李志军 +3 位作者 毕凤荣 张俊红 王霞 邵康 《Journal of Central South University》 SCIE EI CAS 2012年第8期2238-2246,共9页
In order to maintain vibration performances within the limits of the design, a vibration-based feature extraction method for dynamic characteristic using empirical mode decomposition (EMD) and wavelet analysis was p... In order to maintain vibration performances within the limits of the design, a vibration-based feature extraction method for dynamic characteristic using empirical mode decomposition (EMD) and wavelet analysis was proposed. The proposed method was verified experimentally and numerically by implementing the scheme on engine block. In the implementation process, the following steps were identified to be important: 1) EMD technique in order to solve the feature extraction of vibration signals; 2) Vibration measurement for the purpose of confirming the structural weak regions of engine block in experiment; 3) Finite element modeling for the purpose of determining dynamic characteristic in time region and frequency region to affirm the comparability of response character corresponding to improvement schemes; 4) Adopting a feature index oflMF for structural improvement based on EMD and wavelet analysis. The obtained results show that IMF of signal is more sensitive to response character corresponding to improvement schemes. Finally, examination of the results confirms that the proposed vibration-based feature extraction method is very robust, and focuses on the relative merits of modification and full-scale structural optimization of engine, together with the creation of new low-vibration designs. 展开更多
关键词 feature extraction dynamic characteristic finite element model empirical mode decomposition diesel engine block
在线阅读 下载PDF
Evaluation of Performance and Emission Characteristics of Biodiesel Fuel Produced from Rapeseed Oil
12
作者 Momar Talla Dieng Takumi Iwanaga +1 位作者 Yokoyama Christie Yurie Shuichi Torii 《Journal of Energy and Power Engineering》 2020年第3期75-84,共10页
The objective of the present study is to examine and compare the performance and emission characteristic of two biodiesel fuels produced from rapeseed oil via transesterification method.Tested biodiesel fuels(ROME(Rap... The objective of the present study is to examine and compare the performance and emission characteristic of two biodiesel fuels produced from rapeseed oil via transesterification method.Tested biodiesel fuels(ROME(Rapeseed Oil Methyl Ester)and ROEE(Rapeseed Oil Ethyl Ester))were selected based on their properties obtained from an optimization of transesterification conditions.A Yanmar diesel engine has led to evaluating their performance parameters such as fuel consumption rate,exhaust gas temperature and emission characteristic corresponding to nitrogen oxides(NOx),carbone monoxide(CO)and carbon dioxide(CO2).A comparative analysis was carried out using normal diesel fuel tested in same experimental conditions.Fuel consumption rate was measured by observing the volumetric rate from the fuel tank of the engine supported by stopwatch.The exhaust gas temperature and emission characteristic were measured simultaneously by using a testo 350 flue gas analyzer.According to the results,biodiesel fuels showed a higher fuel consumption rate and exhaust gas temperature under an increase of engine speed.They also exhibited lower NOx emission with a slight rise in CO and CO2 emission compared to mineral diesel fuel.ROME exhibited low emission gas compared to ROEE and mineral diesel.It can be evaluated as a promising alternative fuel for diesel engine. 展开更多
关键词 BIOdiesel transesterification reaction rapeseed oil diesel engine emission characteristics
在线阅读 下载PDF
Optimization of Combustion Characteristics and Fuel Injection Timing of a New Type Dual-Pit Combustor Rotary Engine
13
作者 Zhongjia Li Jianfeng Pan +3 位作者 Hongjun Liu Baowei Fan Wenming Yang Abiodun Oluwaleke Ojo 《Energy Engineering》 EI 2021年第3期581-603,共23页
In order to improve the performance of the rotary engine,this paper has designed a new type of dual-pit rotary engine combustion chamber structure,and compares the combustion and emission characteristics with the rota... In order to improve the performance of the rotary engine,this paper has designed a new type of dual-pit rotary engine combustion chamber structure,and compares the combustion and emission characteristics with the rotary engine with a traditional combustion chamber.The existence of the dual-pit combustion chamber strengthens the overall vortex intensity in the cylinder,effectively promotes the mixing process of fuel and air in the cylinder,the maximum combustion pressure in the cylinder increased by 8.6%,significantly increases the diffusion combustion speed,and significantly improves the dynamic performance of the rotary engine.On this basis,the effects of fuel injection timing parameters on fuel distribution,combustion and emission characteristics were studied.Fuel distribution is more even and dispersed during injection in the later stage of compression.When the fuel injection timing was 105°BTDC in the middle of the compression phase,the matching effect of fuel distribution law and ignition scheme was the best.When the injection timing was 75°BTDC and 85°BTDC in the late compression stage,the mass fraction of NOx remained at a low level.The correlation between soot generation and the change of fuel injection timing was weak.When the injection time was 85°BTDC,the soot generation remained at a relatively high level. 展开更多
关键词 Rotary engine combustion chamber structure spray combustion characteristics injection strategy experiment and simulation
在线阅读 下载PDF
船用发动机甲醇-柴油同轴分层喷射燃烧排放特性
14
作者 王洋 孟令超 刘龙 《柴油机》 2025年第2期8-13,33,共7页
由于船用双燃料发动机双喷油器空间布置有限、结构复杂,在船用中速机上探索一种新型甲醇-柴油同轴分层喷射技术,从理论层面探索不同能量比柴油对甲醇燃料燃烧以及排放的影响。结果表明:甲醇-柴油同轴分层喷射喷入不同能量比柴油均可实... 由于船用双燃料发动机双喷油器空间布置有限、结构复杂,在船用中速机上探索一种新型甲醇-柴油同轴分层喷射技术,从理论层面探索不同能量比柴油对甲醇燃料燃烧以及排放的影响。结果表明:甲醇-柴油同轴分层喷射喷入不同能量比柴油均可实现与原机同等功率输出;提前喷射柴油燃料,可在喷射甲醇燃料之前,在缸内形成更好的活性氛围,促进甲醇燃料被引燃并快速燃烧放热;同轴分层喷射引燃模式促进了甲醇燃料的燃烧,且相较于原机有较高的指示热效率;相较于原机,双燃料分层喷射会引起缸内NO_(x)排放增加,但缸内HC、CH_(2)O生成量均有明显降低。 展开更多
关键词 船用发动机 甲醇 柴油 同轴喷射 燃烧特性
在线阅读 下载PDF
基于数据驱动的压气机特性图代理模型构建和优化
15
作者 杨启融 王贺春 +3 位作者 杨传雷 王银燕 赵兴天 牟红雨 《舰船科学技术》 北大核心 2025年第3期89-94,共6页
本文通过对某船用柴油机的匹配涡轮增压器进行研究,得到了压气机的特性曲线。分析了压气机转速、质量流量、压比和效率之间的关系。为了拟合回归和预测压气机特性曲线,使用了一些广泛使用的代理模型,包括Kriging模型、响应面法(RSM)、... 本文通过对某船用柴油机的匹配涡轮增压器进行研究,得到了压气机的特性曲线。分析了压气机转速、质量流量、压比和效率之间的关系。为了拟合回归和预测压气机特性曲线,使用了一些广泛使用的代理模型,包括Kriging模型、响应面法(RSM)、人工神经网络(ANN)、径向基函数(RBF)和支持向量机(SVM)。代理模型用于精确预测涡轮增压器在特定时间的运行参数。采用代理模型对不同速度组的曲线进行拟合,研究了压力比与效率的整体预测建模方法,并通过数据分析了不同训练样本量对拟合精度的影响;通过遗传算法优化后的全转速下的代理模型的拟合精度提高,在样本数量较少时,其代理模型拟合结果的R~2超过95%。 展开更多
关键词 船舶发动机 涡轮增压器 代理模型 机器学习 压气机特性图
在线阅读 下载PDF
喷油正时对氨/柴油双燃料发动机燃烧放热规律和部分排放的影响
16
作者 桑浩 梁俊杰 +1 位作者 吕林 祝能 《武汉科技大学学报》 北大核心 2025年第1期70-80,共11页
以船用单缸柴油机为研究对象,采用氨气预混、柴油直喷的燃烧模式,通过试验方式探讨喷油正时对氨/柴油双燃料发动机燃烧与排放特性的影响。结果表明,与纯柴油模式相比,喷入氨气后,发动机缸压峰值P_(max)降低,着火时刻推迟,燃烧持续期增加... 以船用单缸柴油机为研究对象,采用氨气预混、柴油直喷的燃烧模式,通过试验方式探讨喷油正时对氨/柴油双燃料发动机燃烧与排放特性的影响。结果表明,与纯柴油模式相比,喷入氨气后,发动机缸压峰值P_(max)降低,着火时刻推迟,燃烧持续期增加,最大压力升高率R_(max)减少,CO_(2)和NO_(x)的排放下降,未燃氨和N_(2)O的排放显著增加。在双燃料模式下,随着柴油喷射时刻的提前,缸内燃烧情况改善,P_(max)和R_(max)增大,未燃氨和N_(2)O排放下降,NO_(x)排放上升,碳烟排放先减后增,CO_(2)排放无显著变化;随着负荷的增加,P_(max)和R_(max)增大,但氨气喷射量的增加降低了缸内空气充量,使得着火时刻推迟,燃烧持续期增加,CO_(2)、碳烟和NOx的排放增加,未燃氨和N_(2)O的排放降低。如果优先考虑燃烧平稳性,25%和75%负荷率下的喷油正时最佳值为-5°CA;若以降低温室气体排放为首要目标,25%负荷率下的喷油正时最佳值为-15°CA,75%负荷率下的喷油正时最佳值为-10°CA;若以降低NOx排放为首要目标,25%和75%负荷率下的喷油正时均为-5°CA。 展开更多
关键词 氨/柴油双燃料发动机 喷油正时 放热规律 燃烧特征参数 尾气排放
在线阅读 下载PDF
柴油机隔振器配置对主轴承润滑特性的影响
17
作者 吴鹏 王海兵 +2 位作者 巫立民 张延亭 李梅 《柴油机》 2025年第1期40-45,共6页
以某大功率多缸柴油机为研究对象,采用EXCITE Power Unit软件建立隔振器−机体−曲轴的整机隔振系统弹流润滑仿真模型,对比分析机脚布置位置和隔振器刚度对主轴承润滑特性的影响。仿真结果表明:当机脚支撑跨度增加时,支撑位置的轴承孔位... 以某大功率多缸柴油机为研究对象,采用EXCITE Power Unit软件建立隔振器−机体−曲轴的整机隔振系统弹流润滑仿真模型,对比分析机脚布置位置和隔振器刚度对主轴承润滑特性的影响。仿真结果表明:当机脚支撑跨度增加时,支撑位置的轴承孔位移和倾斜程度增加,主轴承粗糙接触压力升高,此时轴承合力降低,摩擦损失功和平均热载改善;当隔振器刚度提升时,主轴承润滑特性趋于改善,采用刚度方案二(刚度为7920 N/mm)时可获得较优润滑指标,继续提升刚度的收益有限。 展开更多
关键词 大功率柴油机 隔振器 主轴承 润滑特性
在线阅读 下载PDF
国六柴油机轨压和喷油正时对柴油机性能的影响 被引量:1
18
作者 毕玉华 张凯 +3 位作者 黄粉莲 万明定 聂学选 严杰 《内燃机工程》 CAS CSCD 北大核心 2024年第3期59-69,共11页
为优化柴油机性能,基于一台配备了完整国Ⅵ后处理系统的高压共轨直列4缸柴油机,开展了柴油机负荷特性研究,在此基础上研究轨压和喷油正时对柴油机性能的影响。研究结果表明:以适当较小的轨压配合较为提前的喷油正时可以达到较为理想的... 为优化柴油机性能,基于一台配备了完整国Ⅵ后处理系统的高压共轨直列4缸柴油机,开展了柴油机负荷特性研究,在此基础上研究轨压和喷油正时对柴油机性能的影响。研究结果表明:以适当较小的轨压配合较为提前的喷油正时可以达到较为理想的柴油机油耗及排放;轨压和喷油正时对HC排放的影响较小;轨压对柴油机油耗、排温、NOx排放、CO排放的影响较大,且在中等偏高负荷时更为敏感,随着轨压增加了57 MPa,柴油机油耗、排温分别下降了16.1 g/(kW·h)、63℃,NOx排放上升了663×10^(-6),CO排放下降了785×10^(-6);喷油正时对烟度及柴油机氧化催化器前端温度T4、柴油机颗粒捕集器前端温度T5、选择性催化还原系统前端温度T6的影响较大,且在低负荷时更为敏感。随着喷油正时提前6.0°,烟度下降了0.43%,T4、T5、T6峰值出现在轨压为76 MPa且喷油正时为上止点前7.5°时,温度分别为315.3、338.4、329.3℃。 展开更多
关键词 柴油机 负荷特性 轨压 喷油正时 温度
在线阅读 下载PDF
船用柴油机排放耐久性试验方案及分析
19
作者 徐泰富 宋鑫 +1 位作者 王忠俊 陈智君 《舰船科学技术》 北大核心 2024年第11期134-138,共5页
为了改善我国内河及沿海船机的污染物排放现状,我国颁布了GB 15097-2016,并提出了船机及其后处理装置的耐久性试验要求。根据前期完成的几组耐久性试验的特点,对试验方案的制定和实施过程进行梳理。并结合某型中速船机的耐久性试验数据... 为了改善我国内河及沿海船机的污染物排放现状,我国颁布了GB 15097-2016,并提出了船机及其后处理装置的耐久性试验要求。根据前期完成的几组耐久性试验的特点,对试验方案的制定和实施过程进行梳理。并结合某型中速船机的耐久性试验数据,分析环境因素变化对排放特性的影响。分析结果表明,NO_(X)比排放量和劣化趋势受环境因素变化的影响较严重,尤其是在温湿度变化剧烈的节点;PM比排放量的变化规律不明显。为了减少耐久性试验过程中环境因素不确定性的影响,试验方案的实施过程控制尤为重要。 展开更多
关键词 船用柴油机 耐久性试验 排放特性 环境因素
在线阅读 下载PDF
船用柴油机均值模型建模及仿真研究
20
作者 杨传雷 张文乐 +1 位作者 王贺春 王振洪 《应用科技》 CAS 2024年第1期105-111,共7页
柴油机模型的研究是探究柴油机性能、实现虚拟仿真的基础,可缩短仿真计算时间、有效节约柴油机开发成本。本文以RK270柴油机为研究对象,使用GT-POWER软件建立稳态性能仿真模型,在此基础上,采用仿真精度高、计算速度快的平均值法,以C++... 柴油机模型的研究是探究柴油机性能、实现虚拟仿真的基础,可缩短仿真计算时间、有效节约柴油机开发成本。本文以RK270柴油机为研究对象,使用GT-POWER软件建立稳态性能仿真模型,在此基础上,采用仿真精度高、计算速度快的平均值法,以C++语言建立柴油机平均值模型,并归纳通用的平均值模型建模标定校核流程;提出二元响应拟合的方法,解决了涡轮增压器特性参数处理困难的问题,并借助数学工具,获得了压气机主要工作区域内拟合精度较高的模型。完成模型开发后,分析了8组工况下的仿真结果,通过误差分析,验证了模型的准确性,丰富完善了柴油机建模理论和方法,可应用于实时控制模型的动态仿真或者实现与船舶动力系统的交互。 展开更多
关键词 柴油机 性能仿真 建模 GT-POWER 推进特性 平均值模型 二元响应拟合 压气机
在线阅读 下载PDF
上一页 1 2 38 下一页 到第
使用帮助 返回顶部