Simplified Analysis Strategies for Fluid-Structure Interaction in High Speed Turbomachinery

High pressure seals are usually mounted between the rotating and stationary components in high-pressure turbomachinery and often experience intense vibration. These vibrations can interact with the fluid to produce unsteady flows, which can in turn induce structural vibrations that result in machine failure. The reduction of the adverse effects of these vibrations is considered one of the most challenging problems for turbopump design. However, detailed analyses of such fluid-structure interaction problems can be extremely time-consuming and inefficient. The purpose of the present study is to evaluate the effectiveness of simplified, lumped-parameter techniques in analyzing and predicting such behavior, as compared to more sophisticated techniques, with the goal of defining the range of validity for such techniques. A fluid-structure driven vibration is evaluated using a lumped parameter analysis for a wide range of parametric configurations and the results are validated and compared using a bench-top laboratory test rig.