559 / 2019-01-14 20:25:06

Analysis of the Influence of Piston Ring on Gas Leakage in Combustion Chamber

活塞环；Gambit；Fluent；动网格

全体主题 > 先进能源系统

[摘要]活塞环是柴油机组件中非常重要的一个部分，其主要的作用有密封作用，控油作用，导热作用，支承作用。柴油机在工作时会在燃烧室内形成高温高压的燃气，为了防止高温高压气体经活塞与气缸之间的缝隙泄露，造成热效率降低，滑油失效，曲轴箱着火等一系列不良后果，将活塞环放置在活塞和气缸之间，以起到密封的作用。但高温高压气体仍然可以通过活塞环的间隙泄露，所以对活塞环的漏气分析成了一个很热门的研究课题。本文利用Gambit和Fluent软件，在柴油机的高爆发压力下，考虑活塞环的上下移动，忽略活塞环的热传导，采用不可压缩气体模型来简化分析。使用Gambit软件绘制二维活塞-活塞环-气缸流道，然后将二维图形导入Gambit软件划分非结构网格，之后将网格文件导入Fluent进行动网格迭代求解。最终发现经过第一道环的阻拦后，压力已有非常明显的下降，活塞环在环槽中的位置不同，气缸内气体的压力等都会受到改变，当活塞环距环槽上表面距离大时，缸内的平均压力会变大，质量流量变大。

[Abstract] The piston ring is a very important part of the diesel engine . Its main functions are sealing action, oil control, heat conduction and support. When the diesel engine is working, high-temperature and high-pressure gas is formed in the combustion chamber. In order to prevent the high-temperature and high-pressure gas from leaking through the gap between the piston and the cylinder, What lead to the thermal efficiency is lowered, the lubricating oil is ineffective, the crankcase is ignited,so the piston ring is placed. Between the piston and the cylinder to play the role of sealing. However, the high temperature and high pressure gas can still leak through the gap of the piston ring, so the analysis of the gas leakage of the piston ring has become a hot research topic. In this paper, Gambit and Fluent software are used to consider the up and down movement of the piston ring under the high burst pressure of the diesel engine, ignoring the heat conduction of the piston ring, and using the incompressible gas model to simplify the analysis. The Gambit software was used to draw the two-dimensional piston-piston ring-cylinder runner, then the two-dimensional graphics were imported into Gambit software to divide the unstructured grid, and then the grid file was imported into Fluent to solve the dynamic mesh iteratively. It was finally found that after the blockage of the first ring, the pressure has dropped significantly. The position of the piston ring in the ring groove is different, and the pressure of the gas in the cylinder is changed. When the distance between the piston ring and the upper surface of the ring groove is large, The average pressure in the cylinder becomes larger and the mass flow rate becomes larger.