Analysis and Experimental Validation for a Simplified Flame Tube Subjected to Combined Thermal-Acoustic Loadings

Aiming for mastering the analytical techniques on the vibration response of metallic structures under combined thermal-acoustic loadings, a simplified flame tube was used for investigation, both on analytical process and experimental validation. The experiment was conducted under both the room temperature and an extreme temperature of about 450 ℃, and the analysis process based on finite element method (FEM) was developed and implemented in commercial FEM software, correspondingly. The analysis results were validated via experiment, and shows: 1) Under the room temperature, the analysis successfully got the modal frequencies of the flame tube, and the error of vibration response results is less than 15%; 2) The vibration response under thermal-acoustic loadings is highly effected by the temperature distribution, by specifying a supposed temperature distribution, the analysis results of both foundational frequency and vibration level was fitted with the experimental results within the error of less than 15%.