Double　patterning　improves　the　development　of　immersion　lithography,　but　it　brings　new　challenges　including　the　higher　scanning　velocity　of　wafer.　In　this　paper,　considering　two　typical　injection　types,　the　three-dimensional　computational　fluid　dynamics　model　is　developed　to　investigate　the　effect　of　injection　parameters　on　immersion　liquid　during　wafer　scanning.　By　analyzing　the　velocity　distribution　of　immersion　flow　and　normal　stress　on　the　lens,　the　proper　parameters　of　injection　are　proposed　under　the　typical　conditions,　and　the　appropriate　parameters　which　lead　to　effective　renovation　with　low　lens　distortion　are　also　given.