The impeller, also known as the turbine, is a part that converts mechanical energy into fluid kinetic energy. Impeller structure will determine the function of the impeller, the general geometry of different reservoir, will be based on experience and habits to choose different styles of impeller. The more reasonable method is based on the mixing purpose and the formation of the flow pattern. Because of the strong convection and circulation capacity, turbulent diffusion and shearing force, the turbine has been widely used.
The flow direction of impeller design can be divided into two categories, which are radial flow and axial flow. The impeller may be less than two blades, but the impeller used in the oil field drilling fluid usually has 4 or more blades. In order to meet the requirements of economic and drilling fluid characteristics, the blade material is usually stainless steel or carbon steel; the blade can also be a flat leaf, a folded leaf or a helical blade. The blade can be welded on a central disc, or a flat plate with a circular hole is connected with the screw, and the flat plate is fixed on a disc or a connector, the open type turbine is welded on the wheel hub with a mounting groove.