In　this　work,　the　hemodynamic　effects　of　the　type-A　aortic　dissection　in　different　entry　and　covering　entry　tear　positions　were　mainly　studied.　It　provides　a　new　method　or　idea　in　the　field　of　the　aortic　dissection　hemodynamics,　and　it　is　of　profound　significance　to　provide　basic　theoretical　research　on　the　development　of　aortic　dissection　in　the　aspect　of　clinical　judgment.　Two　type-A　aortic　dissection　models　with　different　entry　tear　positions　(Model　1:　The　entry　tear　was　located　at　the　entrance　of　the　ascending　aorta,　Model　2:　The　entry　tear　was　located　at　the　starting　position　of　the　descending　aorta)　were　reconstructed　according　to　the　computed　tomography　(CT)　images　of　the　patients.　In　our　study,　the　thoracic　aortic　endovascular　repair　was　simulated　by　covering　the　entry　tear　(Model　3).　To　clarify　the　hemodynamic　effects　of　entry　tear　and　coverage,　the　comparative　study　on　the　true　lumen　(TL)　and　false　lumen　(FL)　blood　flow　patterns　of　three　models　were　carried　out　numerically.　The　velocity　vector,　flow　ratio,　pressure,　time-averaged　wall　shear　stress　(TAWSS)　and　relative　residence　time　(RRT)　were　calculated　to　evaluate　the　hemodynamic　changes.　The　results　of　this　work　indicated　that　(I)　the　velocity　of　entry　tear　at　the　aorta　entrance　was　higher;　(II)　The　helical　development　of　the　TL　and　FL　might　be　related　to　the　helical　nature　of　aortic　arch;　(III)　The　blood　flow　which　passing　the　FL　of　Model　1,　Model　2　and　Model　3　in　one　cardiac　cycle　were　approximately　26.63%,　13.39%　and　1%,　respectively;　(IV)　The　difference　in　intima　wall　pressure　of　the　TL　and　FL　were　showed　a　strong　pulsation;　(V)　The　TAWSS　distribution　in　TL　and　FL　were　completely　different　(the　TAWSS　in　TL　intima　＞8　Pa,　the　TAWSS　in　FL　intima　＜4　Pa).　In　brief,　the　aortic　morphology　and　location　of　the　entry　tear　were　found　to　have　a　significant　effect　on　the　hemodynamics　of　the　aortic　dissection.　In　addition,　the　CFD　method　is　used　to　obtain　multi-dimensional　hemodynamic　information　such　as　velocity　field,　pressure,　TAWSS　and　RRT,　which　can　help　clinicians　better　understand　the　development　of　type-A　aortic　dissection　and　provide　a　theoretical　basis　for　clinical　treatment.