round tube短语¹⁴⁴⁹⁷²⁺² 基本例句 圆形管 The results show that the local heat transfer at the front part of the drop-shaped tube is similar to round tube, but apparent difference appears behind the detachment point. 结果表明：滴形管束局部换热规律在前端大圆部分与圆管管束相似，但在脱体点以后差别较大； cnki