【摘要】 汽油机湍流预混燃烧的火焰结构具有分形几何的自相似性。利用基于分形理论的燃烧模型对发动机的燃烧过程进行了模拟计算,并将计算结果与试验数据进行了对比。试验采用自行设计的以光学发动机和高速摄像机为核心的系统,通过对拍摄到的湍流火焰照片经过图像处理来获取火焰的分形维数、火焰面积、湍流火焰速度等特性参数。研究结果表明:试验结果和模型计算值吻合得较好,分形燃烧模型是一种有效的模拟发动机工作过程的手段,具有良好的预测精度。更多还原

【Abstract】 Flame structure of turbulent premixed combustion for gasoline engine has the feature of self-similarity of fractal geometry.Based on the theory about fractal geometry,a turbulent combustion model,called as fractal combustion model,is used to simulate engine combustion process.Experimental system in this paper includes an optical engine and a high-speed digital CCD camera.Images of turbulent premixed combustion flame are obtained.By processing in-cylinder turbulent flame images,some parameters like fractal dimension,flame surface area and turbulent flame velocity are acquired.Simulated results have a good agreement with the experimental results.The study shows that the fractal combustion model is an effective and accurate method to simulate engine working process.更多还原