Similar theory of centrifugal pump

Similar condition

Geometric similarity: The two pumps are exactly similar in structure, the ratio of corresponding dimensions is the same, the number of blades and the corresponding Angle are equal.

Similarity kinematic: The liquid flow at the corresponding points in the two pumps is similar, the ratio of the speed size is the same, and the direction is the same (that is, the speed triangle is similar).

Similarity dynamical: The ratio of liquid inertia force and viscous force at the corresponding points in the two pumps is the same.

Meet the above 3, the two pumps are similar. Usually, two pumps are considered to meet similar conditions as long as they meet geometric similarity and kinematic similarity.

Similarity law

Two pumps that meet similar conditions can be approximately considered that the volumetric efficiency, hydraulic efficiency, and mechanical efficiency of two similar pumps are equal, and the following types are established, called the law of similarity.