抄録
In order to control and balance the axial thrust of turbo machine, many types of devices such as balancing disk, balancing hole and sealing system are developed. However most of them are complicated and sometimes cause troubles such as the vibration by balancing disk. In this study, a very simple device of using shallow grooves mounted on a casing wall, known as "J-Groove", is proposed and studied experimentally and theoretically. The experimental result shows that 70% of axial thrust in an industrial 4-stage centrifugal pump can be decreased at the best efficiency point. Moreover, a simple calculation method which can determine the optimum dimension of groove and its location is proposed.
