helical line

• 螺旋线

helical line的用法和样例：

例句

1. The existence conditions of helical equilibrium are discussed as a special configuration of the rod.
   作为特殊的平衡状态，讨论杆的螺旋线平衡的存在条件。
2. The stability of the helical equilibrium is analyzed with phase plane method, and an analytical criterion of stability is revealed.
   用相平面法分析螺旋线平衡的稳定性，导出解析形式的稳定性条件。