Development of model for stability analysis in a balance piston mechanism in turbopump by using active control

Abstract

This study has developed a model for stability analysis in a balance piston mechanism. The balance piston mechanism is employed to suppress an axial vibration in the turbopump. For its high rotational speed and discharged pressure, many turbopumps use balance piston mechanism to balance axial direction thrust, however sometimes axial vibration occurs because of decreased axial damping. It means that the balance piston mechanism has possibility of occurrence of self-excited vibration due to its dynamics. The occurrence of self-excited vibration depends on the structure of the balance piston mechanism. Therefore, the relationship between the stability and the structure should be predicted in advance. The proposed model using an active control can analyze the relationship concerned with the occurrence of self-excited vibration, namely stability and the structure of the balance piston mechanism. Moreover, the optimal structure for the balance piston mechanism can be decided based on a support vector machine.

Keywords

• turbopump
• balance piston mechanism
• active control
• stability