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The recirculation flow exists at the inlet of the impeller when the axial-flow pumps operate at the low flow rate. At this condition, the pump efficiency falls down and the pump system vibrates seriously, sometimes leads to structural damage, so the pump should avoid operating at this unstable condition. Five schemes with different baffles at the inlet of axial-flow pump impeller were presented. 3-D incompressible flow fields, for different baffle schemes, were simulated by using the commercial software ANSYS CFX. The computed results showed that the distance between the baffles and the impeller was the key factor that influences the performance of axial-flow pumps at the condition of low flow rate. Among these five schemes, scheme No.3 was the preferred plan. The flow field at the meridional plane shows that baffles could reduce the backflow at the inlet of axial-flow pump, reduce the pressure at the suction side and increase the lift of the blade, so as to increase the efficiency of axial-flow pumps at the condition of low flow rate.