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一、文献综述为了保证活塞工作应力与其材料强度相比时是安全的,这就需要详细地了解活塞的机械应力和热应力。在最近十五年中,随着发动机功率的增长和分析技术与计算机的发展,已出现了许多计算活塞应力的方法。艾克尔伯(Eichelber)在1923年和1939年发表的论文中,假设活塞的几何形状为轴对称、无限长和薄壳形状,在这种情况下计算活塞头在轴向温度梯度下的热应力和在气体压力下的机械应力。菲茨杰奥吉(Fitzgeorge)和波普(Pope)在1955年应用薄壳理论确定活塞尺寸变化时的应力变化,并以图表形式提供其分析结果。丹尼斯(Dennis)和雷德福(Radford)在1964年将上述结果加以引伸,并考虑到活塞具有下端自由或固定的
First, the literature review In order to ensure the work of the piston stress and the strength of the material compared to the time of safety, which requires a detailed understanding of the piston mechanical stress and thermal stress. In the last fifteen years, with the growth of engine power and the development of analytical techniques and computers, many methods for calculating piston stress have emerged. Eichelber’s paper, published in 1923 and 1939, assumes that the geometry of the piston is axisymmetric, infinitesimal, and thin-walled, in which case the heat of the piston head at the axial temperature gradient is calculated Stress and mechanical stress under gas pressure. Fitzgeorge and Pope in 1955 applied the shell theory to determine the change in the stress at the piston size changes and provided the results of their analyzes graphically. Dennis and Radford extended the above results in 1964, taking into account that the piston has a free or fixed lower end