请教: helix与spiral之间的差别

具体见原文，查了下机械词汇，但还是搞不懂helix和spiral的细微差别之处，但其差别又非常重要
With the significantreduction of the length of the helix shaped channel of the heat exchangechannel 20 compared with the traditional spiral channel type evaporator, thedirect expansion evaporator is easier to be manufactured

helix侧重为三维的螺旋实体，而spiral多为平面的螺旋线，另外，helix有时也被描述为非技术用途的spiral。
以上见解仅供参考。