Local Fatigue Analysis Of Heat Exchanger Structure And Dynamic Response Of Tube Bundle

With the development of the petrochemical industry,the demand for heat exchangers is growing.One fixed tube plate heat exchanger is the most widely used,one of the most widely used heat exchanger.Based on the experience of engineering application of fixed tube plate heat exchanger,maintenance and maintenance data,the main failure mode of fixed pipe plate heat exchanger is not the failure of the whole strength,but the failure of pipe joint and heat exchanger connection leads to the failure of heat exchanger leakage.Therefore,this paper presents a simplified method of geometrical model of heat exchanger with a fixed pipe plate heat exchanger as the research object.The finite element model of heat exchanger is established,and the finite element model is used to analyze the heat exchanger tube sheet and The stress analysis of the pipe joint was carried out,and it was concluded that the heat exchanger had only the design pressure under the influence of temperature,only the shell design pressure,the pipe design and the shell design pressure at the same time,and the influence of the temperature The design stress,only the shell design pressure,the pipe design and the shell design pressure at the same time the role of six kinds of stress distribution and deformation of the situation,to find the heat exchanger tube and tube bundle junction stress,prone to fracture of the site The Then,the strength and stiffness check of the heat exchanger were calculated and the fatigue life of the heat exchanger under six kinds of conditions was predicted by the finite element analysis.Finally,the finite element analysis of the inherent characteristics,modes,harmonic response and transient fluid excitation response of the whole tube bundle of the heat exchanger is carried out,and the influence of the different design of the baffle on the dynamic characteristics of the heat transfer tube is discussed.Due to the existence of temperature difference between the tube-type heat exchanger piping fluid and the shell-side fluid,there is a constant temperature stress in the fixed tube plate heat exchanger,which will superimpose with the mechanical stress caused by the pressure of the tube-side fluid.When the stress is high will be different parts of the heat exchanger caused by different forms of failure,such as the strength of the shell or stability of the destruction of the strength or stability of the tube damage,between the tube and tube plate pull,tube and shell Body connection site damage,tube plate strength damage and so on.In order to improve the heat transfer efficiency,usually using a higher flow rate,resulting in heat exchanger fluid induced vibration caused by the increasing phenomenon of damage.Therefore,it is necessary to analyze the local fatigue of the heat exchanger structure and analyze the dynamic characteristics of the tube bundle,and provide some reference for the design of the heat exchanger in the project.