纵向流 meaning in English

longitudinal stream

( 3 ) using conformal mapping , the longitudinal protrusion height and the lateral protrusion height on the v - grooved surfaces are given , on this basis , some drag reducing features in parallel - flow , cross - flow and enlarge - flow are presented and analyzed ; in addition , drag reducing features with blade - shaped grooves and u - shaped grooves are discussed , consequently , the riblets designing criterions are suggested which will reduce the drag and noise most effectively underwater
( 3 )利用保角变换方法求出v ?型条纹的纵向和横向突出高度，在此基础上得出纵向流、横向流和带角度流动时的降阻特性，并分析结果；而且分析了叶片型条纹和u ?型条纹表面上的降阻情况，提出水下具有最佳降阻效果的条纹表面设计准则。