This paper describes the investigation of the mechanisms of engine front noise generation and the corresponding countermeasures employed in the development of a diesel engine. According to the analysis of acoustic signals and vibration signals measurement, an investigation of the noise source identification in a diesel engine is presented, and that the noise level of the diesel is comprehended. With the sound intensity method, the major sources of the exterior radiation noise of the engine front are surveyed. The research provides the reliable basis for the engineering practice to reduce vehicle noise level. Furthermore, the measuring data of the acoustic signals are compared by measuring noise from surface vibration, and the results are valid.

The vibratory and acoustic behaviour of the internal combustion engine is a highly complex one, consisting of many components that are subject to loads that vary greatly in magnitude and which operate at wide range of speed. CAE tools development will lead to a significant reduction in the duration of the development period for engine as well as ensure a dramatic increase in product quality. This paper presents today's state-of-the-art CAE capabilities in the simulation of the dynamic and acoustic behaviour of engine and focuses on the relative merits of modification and full-scale structural/acoustic optimisation of engine, together with the creation of new low-noise designs. Modern CAE tools allow the analysis, assessment and acoustic optimisation of the engine.

涡轮增压技术从提出至今，已有百年的历史，经过不断地改进与完善，它已被广泛应用于各个工业领域，特别是汽车行业。鉴于该技术的重要性，本文的主旨就在于通过深入探讨涡轮增压技术在汽车行业的运用，从而对该技术的现状进行基本归纳与总结。为此，本文首先回顾了车用涡轮增压技术的发展历程，随后通过重点介绍当前车用涡轮增压器在技术、工艺和材料等方面取得的成果。对该技术的发展现状做出归纳总结，进而对涡轮增压技术在汽车行业的未来发展方向进行基本展望。

在分析一类高速气浮轴承工作原理的基础上，建立其轴径轴承的静态承载力模型，并据此分析出轴承司隙中气体流 量、压强与节流孔孔径司的相互关系，以及在低速运转下受离心力作用的轴径中心运动轨迹。最后，通过模拟仿真并考虑实际工况给出了轴承司隙和节流孔孔径两个关键尺寸。此举为高速气浮轴承的国产化奠定了一个良好的基础。

在分析一类高速永磁轴承工作原理的基础上，根据磁库仑定律建立其轴颈轴承承载力模型。并据此分析出轴承承载力与偏心距及剩磁强度司的关系，由此提出一种提高轴承承载能力的途径。同时考虑因转子质心与几何中心的偏移而造成转动时产生的离心力，分析了高速运转下转子的运动稳定性问题。此举为高速永磁转子一轴承系统的维修与制造奠定了一个良好的基础。