优化活塞销孔形状设计改善燃烧室可靠性

Improve the Durability capacity of the Piston Chamber Based on the Pin-bores Profile Optimization Design

随着爆发压力提高,活塞燃烧室喉口开裂失效有所增加。除了热应力、材料蠕变等引起喉口疲劳开裂外,研究发现,活塞销孔结构对燃烧室开裂也有重要影响。异形孔结构可提高销孔承载能力,但同时提高了燃烧室边缘拉伸应力幅值,降低了顶部可靠性能;通过优化设计销孔结构可提高燃烧室及销孔承载能力。

The crack failure at the rim of the pistons chamber augmented with the trend of the higher pressure recently years in the modern engines, Besides the thermal stress, the creep action of the material and other factors, the structure of pin-bore profile may be another significant factor which influenced the beginning of the initial crack. Further more, the carrying capacity benefited from the profile of the gudgeon-pin-bore, unfortunately, this configuration raised the tension stresses amplitude at the chamber rim, microcrack may be formed and expanded at this realm. As a result, both the carrying capacity of the pin-hole and the chamber could be better by the pin-hole profile optimized.