Study on Analytical Models and Influential Factors of Thermal Stress in Tube Sheet of Heavy Duty Heat Exchanger
|Course||Chemical Process Equipment|
|Keywords||Tube plate Temperature field Thermal stress Fluid-structure interaction Finite Element Method|
The conventional tube sheet design method is based on the elastic shell theory, the equivalent non-porous solid plate instead of the porous tube plate , using a relatively simple formula , curves , charts, design calculations , but these calculations can not accurately consider the tube plate caused by the temperature difference thermal stresses. Currently used finite element method to get the temperature field of the tube sheet by applying a temperature load and convection load calculation , and then find the tube plate temperature stress , but the accuracy of the results has been the concern of many researchers . In this paper, the finite element method, the U- tube heat exchanger tube plate , for example , given the surface temperature of the tube plate ( temperature load is applied ) , given the fluid temperature and heat transfer film coefficient ( convection load is applied ) , including temperature field , including fluid-structure interaction ( fluid-structure coupling analysis ) the three analysis model calculated the temperature field of the tube plate , and thus comparative analysis of different models for calculation of the the tube plate temperature field and thermal stress field results for tube sheet heat the stress field calculation method chosen to provide a reference . In order to study the structure of the tube plate size , the flow field characteristics of the tube sheet heat stress , fluid-structure interaction analysis model analysis to study the impact of these parameters on the the tube plate temperature field and thermal stress field . The results show that as the thickness increases , the temperature gradient in the intermediate portion of the tube sheet area has been reduced , i.e. the temperature change more gently , a total stress on the tube plate . Showed a decreasing trend . The change in the position of import and export , will affect the temperature distribution of the tube plates , which affects the thermal stress of the tube plate . Changing the flow field will cause changes in the fluid flow field in the vicinity of the tube plate , the increase of the flow rate (flow velocity) so that an increase in the temperature gradient of the tube plate , the thermal stress also increases . Fluid properties change will cause the temperature distribution of the tube plate change , resulting in thermal stress distribution also changes , and therefore should be given full consideration in the design process . This part of the research results, and provide a basis for the optimal design of the heat exchanger tube plate .