An Investigation on Occurrence of Backflow Phenomena Caused in Axial Flow Pump - Part I: Downstream Backflow

摘要

Physical source of occurrence of downstream backflow is investigated in this paper. Result indicates that it might be the impeller blades impelling action on the main flow, flowing along the blade surfaces in the rotating flow passage, but might not be the rotating impeller blades action on the separated fluid particles from the blade surfaces caused due to fluid particles collision with blade surfaces and disagreement of fluid particles flow angle with impeller blades blade angle which increases with the decrease in flow rate.