A Novel Stability Analysis Method of the Clamping Connection Structure

Clamping connection structures are widely used in the design of high-pressure hot-end components of various engine series but related instability cases and studies were rarely reported. This paper provides a novel, validated and generally applicable stability analysis method which can be used to analyze the stability of clamping connection structures and identify potentially unstable speed ranges. Several start failures of a type of aeroengine due to excessive vibrations at low speed are taken as a starting point to discuss the instability issues. First, based on the root causes of instability verified through tests, stability conditions are proposed. Second, the novel stability analysis method is introduced based on the “critical swing angle line” and the “limit swing angle line” defined in this paper and its effectiveness is verified by test results. Finally, several directional design considerations for improving the stability of clamping connection structures are derived through this method. With the analysis method and design points proposed in this paper, designers can clarify structural design directions and perform stability analyses on design results from the initial stages of the design process. The conclusions of this paper have value for guiding the design process.