Fundamental Study on Double Rotating Screw Pump with Narrow Gap

In recent years, small and high efficiency low specific speed pump is required. However, it is difficult to design the pump that obtains high efficiency in the range of low specific speed. Especially, ventricular assist centrifugal blood pump which is used in clinical has a similar problem. To overcome these problems, the single screw pump with narrow gap that is one of the positive displacement pump was examined, then the double rotating screw pump was developed. To prevent hemolysis, this pump has narrow gap between the rotor and the stator. The rotor rotational mechanism of this pump is simpler than current single screw pumps, therefore, it is possible to miniaturize it in the future. In this study, the fundamental performance of the new pump was investigated. As a result, characteristic of the pump pressure and the leakage flow was clarified.