external radial boundary外部: outside; external径向: radial; radial direction边界: boundary; frontier; border; ...横向边界层: transversely bounded layer向边界进军: march towards the boundary下载手机词典可随时随地查词查翻译关注微信公众号:chachacidian,回复:外部径向边界,即可在微信中查询翻译