Research on improving the reliability of aerospace components based on PSO-VMD-FFT dense modal frequency identification method

This article focuses on aerospace engine components and proposes the PSO-VMD-FFT method for identifying dense modal frequencies, addressing the challenge of difficult identification of dense modal frequencies in structures. The method utilizes the Particle Swarm Optimization (PSO) algorithm to find the optimal combination of the decomposition level K and penalty factor α, thereby enhancing the decomposition accuracy of VMD. Subsequently, experiments were conducted on a scaled-down model of a rocket engine component using the LMS Testlab experimental platform. The PSO-VMD-FFT method was applied to analyze the measured acceleration response curves, extract modal frequencies, and compare the results with those from LMS software analysis. The relative error was within 3%, meeting the accuracy requirements and enhancing the reliability of structural design and improvement of aerospace products.