基于公差分布和过程能力的发动机压缩比研究

Research on Engine Compression Ratio Based on Tolerance Distribution and Process Capability

发动机零部件的设计公差和生产过程能力不仅会影响零部件的制造成本,还会影响生产制造一致性和发动机性能。发动机压缩比是影响发动机性能的重要参数之一。通过识别影响发动机压缩比的尺寸公差,同时考虑尺寸公差的分布状态,建立了完整的压缩比数学模型。在数学模型的基础上,基于MATLAB的GUI界面,形成了发动机压缩比自动计算模型。该计算模型不仅可以实现通过名义尺寸、设计公差和过程能力参数的输入,计算并分析压缩比分布状态,同时还能通过实际生产数据的导入,计算出实际压缩比等参数。以某款发动机为例,采用该自动计算模型,得到影响压缩比的各个尺寸公差贡献率。

The design tolerance and production process capability of engine parts will not only affect manufacturing cost,but also affect manufacturing consistency and engine performance.The compression ratio is one of the important engine performance parameters.By identifying the dimensional tolerances that affect the compression ratio,a mathematical model for calculating the compression ratio was established.Based on the mathematical model and MATLAB GUI interface,an automatic calculation model of engine compression ratio was formed.The calculation model can not only calculate and analyze the compression ratio distribution through the input of nominal dimensions,tolerances and process capacity parameters,but also calculate the actual compression ratio and other parameters through the input of actual production data.The contribution rate of each tolerance that affects the compression ratio of an engine was obtained by using this automatic calculation model.