Influence of Impeller Diameter on the Performance of Centrifugal pumps.

Abstract The impeller is the most important part of the centrifugal pump because it determines the flow or efficiency of the pump. The design of the impeller and its diameter are very essential when considering pump efficiency. The capacity of the pump is determined from the impeller vanes and channels. The three types of impellers include open impeller, enclosed impeller and semi-open impeller are each designed for a specific application. Impellers are made of cast iron or carbon steel and special alloys depending on their application. The research involves the study of the application of impellers in the centrifugal pumps used by Rand Water Company in Johannesburg. The paper considers how variations in the impeller diameter affect the performance of the centrifugal pump. Simulations were conducted at different diameters of the impeller. The impeller was modelled using AutoCAD and simulated using ANSYS software to determine the performance of the centrifugal pump on different diameters. Calculations were done to compare the results of simulation of the different diameters of 2000mm, 2200mm, and 2400mm. The results show that changing the diameter of a pump impeller affects the flow, head and input brake horsepower of the pump in different proportions. The centrifugal pump gives a high flow rate as the diameter of the impeller increases.