【作者】 赵挺；

【导师】 高青；

【作者基本信息】 吉林大学 ， 车辆工程， 2011， 硕士

【摘要】 汽车发动机舱是个半封闭的空间,对温度场的要求特别高。一方面舱内各种材料的零件如橡胶件、线束对温度有一定的要求;另一方面发动机本身需要适当的散热,以保证在各种工况下都具有最佳的动力性和经济性。如何设计好汽车冷却系统是一项非常重要的工作。发动机舱内部零件众多,而且形状各异,很难用简单的公式进行处理。工程开发第一线的工程师,结合CFD仿真技术能够较真实地反映了发动机舱的真实情况,为项目的开发节省了大量开发成本、缩短了时间周期。本文是基于江铃汽车股份有限公司新款卡车的开发为背景,根据整车正向开发设计为要求,在分析标杆车型的基础上,运用商用软件POWERFLOW对发动机舱的散热特性和流程进行了仿真分析,并应用于实际工程开发。试验结果显示,仿真结果与实际数值非常接近,具有很高的参考价值。主要的研究内容如下:1)标杆车型冷却模块结构参数及性能分析,进行属性目标确定、标杆车型分析、零部件台架试验以及属性目标的分解;2)冷却模块匹配分析计算:结合传统理论计算、标杆对比以及布置分析,确定冷却模块零件系统开发尺寸及性能;3)POWERFLOW软件的参数设定和工程应用:结合工程和属性开发目标的要求,将相关工况及约束条件转化成边界条件进行输入分析,并对输出结果做分析和判断;4)发动机舱流场(速度场、压力场、温度场)分析:评估目标车型在基准工况下(环境温度45℃、2档、29kph时、发动机最大功率点)下,发动机舱流场特性和温度场性能,提出设计优化方案以满足工程目标;5)仿真结果与试验结果对比:依据CFD仿真完成的零部件系统的工程开发,通过大量的台架试验和整车环境模拟,试验证明仿真结果与试验结果的符合性。更多还原

【Abstract】 Under-hood is a semi-enclosed space, high requirements on the temperature. one hand the cabin of various materials such as rubber parts, wiring harness on temperature has certain requirements; On the other hand the engine itself requires proper heat dissipation, to ensure that it has the optimal power and economy under the various conditions. The number of components in under-hood is large , and various shapes, it is difficult to use the simple formula for processing. Application of CFD software can save a lot of development cost, and shorten cycle time.This paper is based on the new trucks for the development of Jiangling Motors Corporation. By means of POWERFLOW software for engine cooling characteristics and flow simulation and analysis are carried out, and applied to the actual project development. Main content:1) a benchmark cooling module structure parameters and performance analysis, attribute the target, a benchmark model analysis, parts of benchmark test and properties of the target decomposition;2) cooling module matching analysis: a combination of traditional theoretical calculation, benchmarking and layout analysis, determine the cooling module parts dimensions and performance;3) POWERFLOW parameter setting and application in Engineering : Engineering development objectives, related conditions and constraints into boundary conditions for input and output analysis, making the analysis and judgments;4) velocity field, pressure field, temperature field analysis of evaluation models in the baseline conditions ( ambient temperature of 45 degrees, 2 gear, 29kph, power point ), the Under-hood temperature field flow field characteristics and performance, the optimized solutions to meet the project objectives;5) the simulation results compared with experiment results : Based on the CFD simulation ,finished parts development, through a large number of bench and vehicle environmental experiments, experiments prove that the simulation results and the experimental results of conformity更多还原