Abstract— In centrifugal pumps, the flow physics and dynamic performances are generally affected by any modification in blades shape and design layout. The investigations of estimating the optimum impeller geometry and the appropriate number of blades with a fitting angle need to find a better insight. At the present time, the dominant verification method used for investigation these characteristics are numerical simulation. Commercial code Fluent (CFD) under ANSYS software has been used for investigation the working characteristics of pump impeller under different conditions by using two different geometrical models. For these purposes, two different impellers with different blades number in 3D configuration are designed by using single arc curved blades design method and submitted for analysis and simulation to determine the best characteristics through comparison procedure. Conventional impeller case used as a base for comparison purposes during recording any changes associated with each individual case such as heads, flow rates and efficiency. The solution of dynamic analysis is carried out to approve that impeller structure can resist and withstand many variable loads and turbulent conditions. Results approved that, the static pressure, total head and efficiency are proportional with blades numbers and blades geometry. Even more, it is found that there are some important parameters have some effects on centrifugal pump performance such as inlet diameter of impeller and blades angle. It can be concluded from this works that suitable predicted results are estimated, and these analyzed results can used and adopted for this type of centrifugal pumps.