<p>Here Centrifugal the pump will only deliver one specific flow rate. Therefore, to control the flow of a centrifugal pump, simply <strong>set the output pressure to the point on the P-V diagram that allows the pump to deliver the desired flow rate</strong>. The output pressure of the pump is set using a back pressure regulator.Fluid enters the rapidly rotating impeller along its axis and is cast out by centrifugal force along its circumference through the impeller's vane tips. <strong>Reducing the speed of a centrifugal pump reduces the pump discharge pressure by the square of its speed</strong>. Therefore, the discharge pressure will be approximately 64 percent of the full speed discharge pressure when the pump is operated at 80 percent of speed. for more download this file. </p>