The history of centrifugal pump can be traced back to the invention of the circulation centrifugal pump intended for dealing with hot or cold water mainly in heating systems. Generally speaking, this traditional centrifugal pump is an inline pump and consists of a standard motor and shaft seal for which is also ideal for air conditioning systems and other industrial systems. After that end suction centrifugal pump was developed and introduced to the centrifugal pump market with a lot of variants in terms of different types of shaft seals, impellers and pump housings.
As a matter of fact, the combination of these parts is mainly determined by the type of the pumping fluid, temperature and pressure. As a result of the theoretical analysis of the history of centrifugal pump, more centrifugal pump solutions have been released and their physical quantities are gradually settled by experts such as the pressure of the volute inlet and the angles between radial and the radial components since they are imposed at the calculation domain while the radial velocity is dependent on the interior centrifugal pump domain within the outlet boundary. Another quantity of the centrifugal pump needs to be settled by the physical flow rate conditions at the outlet of domain in spite of the remaining interiors that are in different boundary conditions among which the most appropriate one is marked by downstream static pressure. However, due to the centrifugal pump swirling flow, the static pressure is not uniform and is fixed at the reference point so that the pressure ratio between this point and the upstream point can be calculated in an accurate manner.
On the other hand, the centrifugal pump permeability condition can be met at the solid surfaces even though some kinds of the centrifugal pump has volutes in the shape of cross sections at the corners and the swirling component is equal during the centrifugal pump functioning procedure because the velocity can make adjustment as soon as possible. As a matter of fact, the geometry of the centrifugal pump volute and the generated mesh are one of the external illustrations of the centrifugal pump history since the inner wall of the centrifugal pump has a constant radius while the outer wall has a spiral shape that is located in the upper part of the volute. Therefore, we can see from the centrifugal pump history that to achieve an optimal balance between friction and working efficiency, the key is designing a quality centrifugal pump impeller seal so that the risk of friction can be reduced and the possible noise can be cut to the minimal amount even though this requires a high standard of precision and assembling and may result in higher centrifugal pump production costs.