2026-07-18 23:15 浏览次数 38
洼地
1. a depression (as in the bed of the sea) due to downward bending of the earth's crust
three kinds of devices of drag reducing are presented: swept wing-tip, stage by stage swept wing and downbend wing-tip.
介绍了三种翼梢减阻装置:后掠翼梢、分段后掠机翼和下弯翼梢。