短語詞組短語vortex x sheet 渦片vortex surface sheet 渦麪vortex sheet model 渦漩片模式curved vortex sheet 曲渦流層horseshoe vortex sheet 馬蹄形渦麪vortex sheet method 渦片方法vortex sheet rollup 尾渦卷曲vortex sheet spectrum 渦漩片譜up of vortex sheet 渦麪卷起 返回 vortex sheet