A simulation is carried on three swirling flow with different nonaxisymmetric tangential injection in a horizontal straight pipe to find if neglect their deflations whether they equate to axisymmetric module . a conclusion can be found that when nonaxiwymmetric conditions are occurred , there will be deflections near entrance that are different from axisymmetric condition , and these deflections will be erased on area far from entrance 另外對(duì)水平圓管中三種非軸對(duì)稱切向入流按軸對(duì)稱近似計(jì)算時(shí)進(jìn)行數(shù)值比較分析,發(fā)現(xiàn)三種非軸西安理工大學(xué)碩士學(xué)位論文對(duì)稱切向入流條件下在近入口處出現(xiàn)很大的偏差,這種偏差不能忽視;而經(jīng)過(guò)充分的發(fā)展之后,這種差別將被抹平,即在離入口較遠(yuǎn)的區(qū)域各種情況的計(jì)算結(jié)果與軸對(duì)稱條件比較差別不大。