【作者】 宁成钢；

【导师】 叶盛焱；

【作者基本信息】 武汉理工大学 ， 动力机械及工程， 2007， 硕士

【摘要】 发动机的进气过程是发动机工作循环的关键因素之一。进气系统中，进气道的结构对直喷柴油机的动力性、经济性、振动、噪声以及排放都有很大的影响。所以，设计出合适结构的螺旋进气道进而产生适当的涡流强度和流量系数对发动机相当重要。相对传统的经验设计和稳流试验结合的气道开发方法，三维逆向数值模拟进气道的方法时间短，可以较容易得到综合评价参数以及气道和缸内的微观流场信息。随着计算机技术的发展，计算流体动力学(Computational FluidDynamics，CFD)技术日趋成熟，被应用于发动机进气道流场分析也越来越多。目前国内外应用较广的CFD软件如：Fire、Fluent都是比较精确的流场分析软件。本文即是应用Fluent进行发动机进气道稳态流场分析。本文主要工作为：1、综述了柴油机螺旋进气道的开发方法及有限元相关理论；2、对不同的进气道评价试验方法及技术进行了阐述和比较；3、对三维建模软件Pro／e、分析前处理软件Gambit及流体分析软件Fluent进行了介绍；4、简述了流体所遵循的物理规律和流体模型；5、采用逆向工程建立了6105QB发动机螺旋进气道的三维几何模型，选定了气体流动的数学模型和数值方法。应用Fluent对所建模型进行了流体分析，并利用Microsoft Visual C++6.0编写了相应的性能参数(涡流比、流量系数)计算程序代码。评价方法是采用Ricardo评价法对模型性能参数进行计算的；6、比较分析了不同气门升程下发动机的无量纲涡流比和流量系数，给出了气道详尽的流场信息，并提出了改进意见。所得计算数据较为合理，对螺旋进气道设计具有理论指导意义，可以缩短进气道设计开发周期，减少研发经费，有效提高新产品的研发效率。更多还原

【Abstract】 The process of intake charge is the linchpin of an engine’s work circulation.The structure of intake port directly affects the power, economy, the strength of swirl and flow coefficient in the diesel engine in the intake system. Compared with the traditional design method which depends on experience and test, the three-dimensional numerical simulation has the below traits: short time, easily getting value parameters and information of microcosmic fluid field.With the computer technology’s improvement, Computational Fluid Dynamics (CFD) also has gradually become mature and been used more and more to simulate intake port. At present, the CFD software such as: Fire, Fluent, which be applied widely at home and abroad, all is accurate software. This thesis chooses the Fluent to simulate the intake port.In this paper, the author mainly does below work:1. Summarizes the different methods of intake port design and finite element theory;2. Compares and summarizes different appraisement means of intake port;3. Introduces the Pro/e, Gambit and Fluent;4. Mentions the fluid science rules and models;5. Builds and analyses the three-dimensional model of 6105QB.In the meantime, applies appraisement means of Ricardo to analyses the capability parameters. Applies Microsoft Visual C++6.0 to write program to calculate capability parameters (swirl ratio, flow coefficient).6. Analyses the swirl rates of different valve lift and gives the particular information of fluid field and the opinions for improvement;The data is comparatively logical, in the meantime it has direction meaning and can help shorten exploitation period and reduce research outlay and boost research efficiency of new production.更多还原