整车电路系统引起汽车自燃原因分析及验证方法

分析整车电路系统引起汽车自燃的原因,同时通过对整车电路系统引起烧车的两种主要原因——过载与短路现象的分析,进行整车电路系统设计验证,用模拟过载及短路保护测试的方法,验证系统设计的匹配性、合理性,从而有效地预防汽车自燃现象的发生。     

排气管内二维非定常流动的计算研究

为了优化设计排气管形状，本文研究了柴油机排气管内二维非定常湍流流动的计算，排气管与气缸交接处的边界条件由实验结出，湍流模型采用k－ε模型。计算了一根3缸模型排气管内排气流动变化，计算结果与实验结果吻合良好。该研究对排气管的形状设计有一定的应用价值。     

The PROFILE project: an overview

The EC MAST project PROFILE (Processes in Regions of Freshwater Influence, ROFIs) aims to develop process understanding and tested numerical models for ROFIs. This includes the role of physical processes controlling water-property distributions, suspended sediments controlling the availability of light, nutrients and phytoplankton growth. The project comprises: (1) construction of a 3D nearshore model, with high resolution (1 h and one km approx.) and a framework coupling modules for hydrodynamics (tides, effects of winds and waves, currents, temperature, salinity, turbulence and diffusivity), sediments, plankton, nutrients and oxygen, (2) investigation of methods to include ROFI model detail in coarser shelf-wide models, (3) specific tests of model components against measurements, (4) tests of model calculations against measurements in contrasted ROFIs, (5) systematic observations suitable for these model tests (time-series over a seasonal cycle for dynamics and intermittency, good vertical resolution and spatial surveys) of the contrasted Rhine, Clyde and Thermaikos Bay ROFIs, complementing earlier measurements in the ROFI areas of the Rhine, German Bight and Po, (6) interpretation and comparison of the contrasted ROFIs' behaviour, (7) a defined set of observations, model code and output suitable for subsequent integration and promulgation as test data and a nearshore model for wider use.     

Modelling physical processes of haline stratification in ROFIs with application to the Rhine outflow region

A physical and numerical study is made of the processes governing the stratification and circulation in ROFIs (Regions of Freshwater Influence) where there is an important impact of wind and tides. Observations in the Rhine ROFI showed that the salinity field consists of a mean and a tidally oscillating part. The physical processes are first analysed using the analytical solutions from a one-dimensional two-layer model. A justification is given for the neglection of non-linear advective terms in the equations of momentum and salinity. The dimensionless forms of the solutions can be expressed in terms of a series of dimensionless numbers. It is shown in particular that stratification and cross-shore circulation largely depend on the balance between rotation and turbulent diffusion, which depends in turn on parameters such as the Ekman number, the bottom friction coefficient, the eddy viscosity ratio and the depth of the layer interface. Surface winds either enhance or destroy stratification depending on the wind angle. The response to wind forcing is discussed using classical Ekman theory. To verify the analytical theory numerical tests are performed with a point model including an advanced turbulence closure scheme. Differences arise due to the non-linear interaction between turbulence on the one hand and current shear and stratification on the other hand. It is shown in particular that the amplitude of the tidal forcing and the off-shore horizontal salinity gradient strongly affect the semi-diurnal and semi-monthly variation of stratification. The effect of the wind is found to be in good agreement with the analysis of the two-layer model. Finally, the numerical model is compared with existing observational data in the Rhine ROFI for October 1990.     

船用HND三燃料发动机研究进展及发展趋势探讨

由于船用发动机节能减排的需要,使用清洁能源作为替代燃料成为一个重要的发展方向。结合国内外针对氢-天然气-柴油(HND)三燃料发动机的研究,分析此类发动机燃烧性能和排放性能。增加氢气在混合燃料中的比例使得发动机缸内压力峰值提升,缸内温度增加,有助于提高发动机效率和机动性;一氧化碳、二氧化碳、总碳氢排放随氢气比例的升高而减少;氮氧化物排放有所增加;颗粒物排放显著减少。随着氢能源战略的发展,船用HND三燃料发动机在未来有望得到商业化推广应用。     

燃烧合成焊接Al2O3陶瓷的研究

以Ｎｉ－Ａｌ－Ｔｉ元素粉末为反应焊料,采用加压燃烧合成技术对Ａｌ２Ｏ３陶瓷的焊接进行了研究。结果表明,经反应合成的含５％Ｔｉ的Ｎｉ３Ａｌ以及Ｎｉ２ＡｌＴｉ金属间化合物在文章实验条件下实现了Ａｌ２Ｏ３陶瓷的焊接。在反应焊料中加入一定量的Ａｌ２Ｏ３陶瓷颗粒获得了带有Ａｌ２Ｏ３ｐ／Ｎｉ３Ａｌ（Ｔｉ）复合焊缝层的陶瓷焊接接头（复合焊接接头）．加压燃烧合成焊接法具有材料制备和连接一次完成的优越性。     

喷嘴凸出高度对单缸机气缸内燃烧过程影响研究

对某型号的单缸机进行仿真预测计算,分析不同喷嘴凸出高度对柴油缸内燃烧过程的影响.     

内燃机数字化的技术状态管理

阐述了在内燃机设计过程中应用产品数据管理(PDM)系统进行的技术状态项目的管理、标志方法,为内燃机行业改变传统的设计理念,有效开展数字化技术状态管理提供借鉴.     

DME部分预混压燃与缸内直喷复合燃烧的研究

在单缸二甲醚发动机上开展了DME部分预混压燃与缸内直喷混合燃烧(PCCI-DI)特性的研究。结果表明:DME PCCI-DI发动机具有较低的最高爆发压力和压力升高率。PCCI-DI DME发动机燃烧过程也表现出明显的两阶段放热特点,和HCCI DME发动机相比,两个放热峰值有所下降,第1个放热峰值位置基本不变,第2个放热峰值后移到上止点略后位置。     

溶液燃烧法制备TiV_(0.1)Mn_(0.1)Er_(0.01)O_x催化剂催化还原NO_x的性能研究

为了拓宽选择性催化还原NO_x钒基催化剂的活性温度窗口,采用溶液燃烧合成法制备了TiV_(0.1)O_x催化剂,依次加入Mn元素与Er元素形成新的催化剂,分别对它们进行了SCR活性及选择性测试,发现负载Mn元素可以提高钒基催化剂的低温活性,同时也会降低钒基催化剂的高温活性,负载适量的Er元素可以提高钒基催化剂的高温活性和N_2选择性。利用N2吸附脱附法进行BET比表面积和孔容孔径分析,发现负载Er元素增大了比表面积,进而提升了催化剂活性。利用X射线衍射(XRD)图谱进行晶体结构分析,所有催化剂样品均没有发现VO_x,MnO_x或ErO_x的衍射峰,说明溶液燃烧法制备的催化剂活性组分在TiO2颗粒上呈无定型态分布,分散度高。最终优选出最佳Mn和Er比例的TiV_(0.1)Mn_(0.1)Er_(0.01)O_x催化剂,在160~470℃之间保持80%以上的NO_x去除率。