Method and device for modeling failure physical model of pipeline with welding seam of rocket engine

The invention provides a modeling method and device for a failure physical model of a pipeline with a weld joint of a rocket engine, and relates to the technical field of equipment reliability research. Obtaining a residual stress strain field in the welding process; wherein the pipeline geometric model comprises a welding seam structure; then, based on the residual stress strain field, dynamic response analysis of a welding structure is conducted on the pipeline geometric model under the vibration load effect, and a frequency response function is obtained; and calculating the service life of the welded pipeline of the rocket engine based on the frequency response function. In this way, the phenomena that the mechanical fatigue performance of a welding seam material of a welding structure, a residual stress strain field generated in the welding process and the inherent frequency change under the action of residual stress and the like are comprehensively considered, and therefore the comprehensiveness of a fai